How Big Of A Water Heater Do I Need For Radiant Heat

How Big of a Water Heater Do I Need For Radiant Heat

How much of a water heater do I require for radiant heat: After a long and exhausting day, you’ll appreciate some gentle warmth in your personal space. When you have a buddy, such as a radiant heater, for your needs, life becomes more enjoyable in a cool atmosphere.

How Big of a Water Heater Do I Need For Radiant Heat

They are often regarded as the greatest wood heater available for any space, among a variety of options. However, because they do not have the same size capabilities as a radiant heater, they are frequently avoided. They move on to other options that are not as successful as the first. In order to better serve you, I’ve chosen to assist you with the radiant heater size questions and other matters. As a result, let’s talk about “How much of a water heater do I require for radiant heat.”

How Radiant Heater Work Inside Your Room?

Unlike other types of heaters, radiant heaters transfer heat. It instantly distributes heat across the entire room area. It is necessary to place a panel either on the floor or on the ceiling. Because they are more functional than the ground, the floor has frequently been used. Radiant floor heaters are also known as radiant floor heaters when they are put on the floor. Infrared radiation is emitted by the system to heat the space that you require. You can think of it as akin to a fire. If you are standing close to it, you will feel the heat emanating from it.

The same function has been implemented in the radiant heater, and it functions in the same way that your room heating system does.

Procedure To Size The Radiant Heater

You will need to have a few statistics on hand in order to make the best option possible when it comes to radiant heaters. The majority of the phrases that I will use to size the radiant heater will be ones that you are likely to encounter on a regular basis. It will not take you on a journey through an unfamiliar universe. Even if you are a complete novice with no prior experience, you can do the task. All that is required is that you follow the procedures and work as directed. It is a small amount of additional labor, but it will pay off in the long term by allowing you to take use of the radiant heat whenever you require it.

Step 1: Accurate measurement of your room

When it comes to measuring a room, a variety of approaches are presented on the head. I’d want to speak about the one that has been claimed to be the most often utilized. For this activity, you’ll need a tape measure or a computerized measure of some sort. Reduce the length of the room by a factor of two. In certain cases, furniture might create obstructions on the way, so attempt to remove it if at all possible. Start at one wall and finish at the opposite wall to complete the cycle. Although you may be able to see the number on the screen for the digital measuring tool, the analog system will need to be copied first.

Make a note of the number, and then repeat the process for the length of the room. After you’ve obtained the digits, you’ll need to enter them into the formula as follows:

Length (ft.) x Width (ft.) = area (sq. ft.)

You already know how much square footage your room is going to be. If you have a high ceiling, the height of the ceiling may also be a source of concern. You must also determine the cubic feet of the room in which you intend to install a radiant heater, and you must do so before proceeding.

Step 2: Calculating your heater size need

Every room heating program, on average, necessitates the use of around 10 watts of heating power for every square foot of space. In other words, if I suppose that your room is 200 square feet in size, the math will be as follows.

200 x 10 = 2000 watt

Once you’ve determined the correct measurement for your home, you can simply plug the results into the formula to determine the size of your radiant heater. The equation will provide a decent crackdown of the number, which will make the decision of a radiant heater much easier for you to make.

How Many Btus Do I Need For a Radiant Heater?

There are a variety of instances in which a radiant heater is required for your room heating. You, on the other hand, are concerned about making the appropriate choice. If these items are true, it may be possible for you to gain some advantage in the process. A typical household heating system produces between 25 and 35 BTU per square foot, depending on the model. Living in an older home with inadequate insulation might cause this figure to become significantly higher than the average. It can reach speeds of up to 40 mph, although this is an extremely unusual occurrence.

Are Radiant Heaters Worth IT?

When it comes to the advantages of using a radiant heater, there is an almost limitless amount of factors to consider. A typical problem with most heaters is duct loss, which is one of the most prevalent problems. The radiant heater, on the other hand, has dealt with the problem and provided you with some respite. The comforting amount of radiant heat eases your nerves and provides you with a sense of security. It is not intended to cause any allergies in consumers, as is the case with the other heating systems on the market.

Receiving a large energy bill at the end of the month is something that no one enjoys.

Aside from that, the installation is also accurate and rather straightforward to do.

Final Verdict

So now you have all of the information you need to make an informed decision about your radiant heater. It is necessary to do the measurements in the proper method and put them to use. I hope it will be of assistance to you in your duty and make it simpler for you to make the best option possible for you. It is my hope that this post on “how large of a water heater do I need for radiant heat” may be of assistance.

sizing a water heater for radiant heat

Welcome! The following are the website’s rules, as well as some suggestions on how to best use this forum. To locate a contractor in your region, please click here. If you’re installing a radiant heat system, is there any rule of thumb you may use when sizing a water heater? Alternatively, does anyone know how to size a water heater for use with a radiant heating system?

Take, for example, the following scenario: I require 35,000 btu’s for a radiant system and 120 degrees for the water. The delta t in my equation is 10 degrees. Thank you for any assistance you may provideMike B. 0

Comments

• You provided an answer to Your Own Question. I size all of my equipment based on how much heat it loses. If your loss is 35,000, you’ll need a heating plant that can provide 35,000 in revenue. Using a water heater for radiant applications is something I personally do not like. Heaters are extremely inefficient, have a life expectancy of between 6 and 10 years, and restrict my ability to handle a whole heating system in one location. I only require those 35,000 btu’s when the temperature outdoors is below zero. I’d want to ask you a question. If you were buying a new BMW, would you go for the cloth inside or the leather interior? In this situation, the comfort and efficiency of radiant heat are provided by the BMW, while the water heater provides the comfort and efficiency of radiant heat. A bad installation leaves a nasty taste in the mouth that is far longer lasting than a low price that is too good to be true. 0
• I completely agree with youI completely agree with you. I get a lot of calls from individuals in the midwest and southern states who want to utilize their water heaters for heating since that is all they are used with. Their heating loads can reach 6,000 BTU’s at times, and I am not aware of any boiler that can meet those requirements, even a condensing-modulating type. Thanks, Mike B. is a professional photographer based in Los Angeles. When it comes to water heaters, you must include DHW needs in the radiant load calculation if the water heater is used for both heating and cooling (and note, for some codes it is not legal to do dedicated heating with a water heater that is NOT doing DHW). As a result, you’ll require 35kBTUs in addition to whatever you’ll use for residential use. When your water heater is producing 35kBTUs per hour, you need something a little more upmarket than a typical water heater. You don’t need to at 8kBTUs/hr. Design for Rockport Mechanical in the picturesque town of Rockport, Maine. Rob Brown The Lochinvar Knight WB050 is a number zero. You may, however, utilize an electric boiler, which can operate with inputs as little as 1000 watts (1 KW). Electric boilers are built more solidly than water heaters and are generally more dependable. Some electric boilers are equipped with pump relays that are integrated right into the unit, and some even have outside resets to save even more money over a regular electric hot water tank. The only drawback is that an electric boiler consumes electricity, which is typically substantially more expensive to heat with than natural gas. However, they are far less expensive to purchase and install, and they would most likely just represent a little blip on the electricity bill if the load is fairly tiny. However, when it comes to bigger loads, they are typically prohibitively expensive as compared to a gas boiler (at least right now). Smaller condensing modulating gas boilers, in particular, are something that North America, in my view, could need more of. The Lochinvar Knight wall mount WB050 modulates from 10,000 to 50,000 inputs, and it is the smallest unit I am aware of in this class (so about 9,000 to 45,000 output roughly). These are the next two smallest units: the IBC VFC 15-150 (wall mount), which modulates from 15,000 to 150,000 BTUH, and the Triange Tube, which modulates from 16,000 to 60,000 BTUH (also wall mount). The next largest unit is the Lochinvar Knight (either wall or floor mount), which modulates from 16,000 to 80,000 BTUH (either wall or floor mount) (inputs). In the event that someone could develop a boiler that modulates up to 30,000, it would be quite useful for a wide range of applications, from boiler back up to minor loads to someone who just wants the redundancy of two boilers rather than one larger one with a higher turn down ratio. Due to the price differential in the utilities, even on minor loads, you may get a decent payback as compared to heating with an electric boiler. Journeyman Gas Fitter – Certified Hydronic Systems Designer – Class ‘A’ Gas Fitter Plumber 0
• sThanks Thank you very much for your assistance, it was really appreciated. Thank you one again. Mike B. is a professional photographer based in Los Angeles. 0
• It appears like you have a fantastic opportunity to sell some solar. Find the source of the itch because you have a golden chance. With the potential to provide a 30 percent tax credit, you may perform both residential and radiant heating and cooling systems. A bad installation leaves a nasty taste in the mouth that is far longer lasting than a low price that is too good to be true. 0
• sefficiency Water heater efficiency is assessed based on its intended use (dhw) and takes into account standby losses, cycling time, and stack losses, none of which are applicable to a heater operated as a boiler, especially when situated in and with its chimney in a heated environment and operating continuously. jc 0
• And that is YOUR point. Curiosity got the better of me:-). ME As opposed to “You got what you paid for,” it is more of a case of “You DIDN’T receive what you DIDN’T pay for, and you are NOT going to get what you thought you were going to get in terms of comfort.” This is a rip-off of Heatboy. 0
• We haven’t all utilized a water heater for a little radiant project at some point. Personally, I like the notion of having a single heat source that can be used for both DHW and heating. Furthermore, there is no reason to combine the two loads when determining the appropriate water heater size. During peak DHW consumption, just lower the thermostat a few degrees. And remember to utilize your common sense. Often in error, but never in question. 0
• Hello, Mark. I was responding to Chris, who is adamantly opposed to hot water heaters. One issue is because they are less efficient than boilers, which is one of the main reasons. It was my intention with my statement to call into question his findings because there are no data available that specify the efficiency of a water heater in a heating application, nor the efficiency of a boiler in a district heating application. The standard 66 percent vs 90 percent efficiency comparisons are simply not comparable and can not be relied upon as evidence when making a decision. jc 0
• I see what you’re saying. And do correct me if I am incorrect, but any product’s theoretical annual fuel utilization efficiency (AFUE) values can never surpass its instantaneous thermal efficiency numbers, yes? So, if a water heater’s immediate efficiency is 80 percent, it can’t have an annual fuel utilization efficiency (AFUE) greater than 80 percent, correct? BTW, I’m not a huge fan of them either, despite the fact that I used to possess one. Thank you for taking the time to respond. ME As opposed to “You got what you paid for,” it is more of a case of “You DIDN’T receive what you DIDN’T pay for, and you are NOT going to get what you thought you were going to get in terms of comfort.” This is a rip-off of Heatboy. 0
• I have no notion what the true values are, nor do I have any concept what the immediate thermal efficiency of the system is. I do not hold a professional position. I only know that the statistics that are commonly reported are based on a variety of testing processes and are not reliable indicators of which heating unit would be more cost-effective. 0
• Hello, Alan. Yes, I have utilized a water heater for a very tiny radiant load on a couple of occasions in the past. It was a cellar that had been converted into an apartment. The load was around 10,000 btu. A Nat Gas Power Vent was used. The radiant was created using a flat plate, and the domestic was created using a heater. It turned out to be a fantastic solution for the application. He utilized 35,000 btu’s in his post, which you can read here. This does not appear to be a minor load, and the application should not make use of a water heater. The heat loss from my 2,000 sqft house is around 35,000 btus per year. I, for one, appreciate economic restraints, but if you can’t afford to do it now, at the very least design and set it up to do it later. Water heaters are inexpensive, and I see no reason why he shouldn’t be able to utilize one as a temporary solution until he can afford a modern HVAC system. If money isn’t a problem, he should at the very least make a decision based on all of the facts he has available to him to hand. Merry Christmas and Happy New Year! A bad installation leaves a nasty taste in the mouth that is far longer lasting than a low price that is too good to be true. 0
• sJRC In fact, I feel that the efficiency of the system is in many respects far more significant than the efficiency of the heating plant. The fact that a piece of equipment generates energy at a specific AFUE is impressive
• But, what you do with the energy that you have just paid to generate has a significantly greater influence on your fuel cost. Although I suppose I have utilized ratings in some of my earlier postings, I do not recall ever having done so. In order to avoid using them, I’ll provide a couple of my justifications. An electric water heater will produce the same amount of btu’s on a daily basis, regardless of the temperature outside, which might cause a structure’s heat loss to vary on a daily basis. A water heater will constantly maintain a tank temperature, regardless of whether or not there is a need for heat or domestic hot water at the time. Due to the nature of my water heater, I am stuck with attempting to make use of btu’s that I really didn’t need to be produced in the first instance. It doesn’t make any sense to spend money on something that I won’t be able to put to good use. I know, I’m going to blow some of the money I’ve been trying to save up. A bad installation leaves a nasty taste in the mouth that is far longer lasting than a low price that is too good to be true. Zero
• Chris, I agree with all of your concerns, however the first, system design, makes significant inroads into the last, standby loss, because the heater loses very little heat during the cold season if it and the vent are maintained in a warm location during the cold season. Outdoor reset has been a major source of frustration for me for a long time, and the only answer I’ve found has been to manually reset my VW depending on weather reports—I don’t have a BM. jc 0
• Is it possible to reset a pain? There are just two reasons why a reset might be a hassle. The first is that you have the incorrect curve selected. The second problem is that there aren’t enough emmitters to acquire the btu’s you require. I can see why you feel you have no alternative except to manually reset the system yourself. If this is the case, you either not have a great deal of confidence in the contractors in your region, or you must have had some negative experiences and be fed up with them. A bad installation leaves a nasty taste in the mouth that is far longer lasting than a low price that is too good to be true. 0
• OKI believe we have understood one another. Whenever a customer comes to me with a request to heat a room, I’m tempted to recommend a combined water heater for practically any size under 1,000 square feet, especially if there are more than one heating zones. If the temperature rises over that or the heat loss is significant, I switch to a boiler. Often in error, but never in question. Wizard is accurate
• The result is zero. Due to financial constraints, I utilized a 50-gallon water heater to heat my 1400-square-foot home for ten years. 35 kilowatt-hours. The Lochinvar WB-050 was acquired with the help of a 30 percent tax credit as well as an additional $500 utility refund. By the way, the boiler, which was ordered and paid for on December 17, will not be delivered until January 15. The team was three weeks behind schedule last year as well. When the weather was warm, the water heater had a tendency to overheat. This is especially true if there is a lot of solar heat gain in the area. The ability to lower the thermostat on bright mornings became second nature to me. During those ten years, on the other hand, I never got cold. 0
• Please inform me of the existence of the Lochinvar Knight WB050. Send me an email letting me know how that little Knight wall mount works out for you. I’m interested in installing the WB050 in my house because it’s the smallest Mod-Con available and my house’s heat loss is around 17,700 BTUH at 18 degrees Fahrenheit (1000 sq. foot rancher in a suburb of Vancouver, BC). It will be used in conjunction with the Squire 30 Gallon Indirect. Journeyman Plumber – Class ‘A’ Gas Fitter – Certified Hydronic Systems Designer – Class ‘A’ Gas Fitter In addition to the balancing valves, Chris, the only controls I have are the manual temperature adjustment on the heater and a line voltage thermostat on the pump. If it’s okay with you, I’ll forward the contractor’s query to you. 0
• You Have Complete Freedom to Do Whatever You Want. It’s a customer of yours. I would expect someone of your caliber to provide them with options and your best professional judgment. A bad installation leaves a nasty taste in the mouth that is far longer lasting than a low price that is too good to be true. One of My Points is 0
• You have just a very small amount of influence over the system. A bad installation leaves a nasty taste in the mouth that is far longer lasting than a low price that is too good to be true. I am in complete command of the situation. Chris, it’s just that it doesn’t happen automatically. 0

You provided an answer to Your Own Problem. Heat loss is taken into consideration when sizing all of my equipment. A heating plant that will produce 35,000 BTUs is required to offset your 35,000 loss. Using a water heater for radiant applications is something I personally do not like doing. Warm air heaters are extremely inefficient, have a life span of only 6 to 10 years, and restrict my ability to control a full heating system. It’s only when it’s below zero outside that I’ll need those 35,000 btus.

• When buying a new BMW, would you opt for a cloth interior or leather seats?
• A bad installation leaves a bitter taste in the mouth that is far longer lasting than a cheap price with a sweet taste in it.
• People from the Midwest and the South are calling me, requesting that I use a water heater for heating because it is all they are familiar with.
• Thanks, Mike B.
• It is not necessary to include DHW demands in the radiant load when using a water heater that is capable of performing both functions (and note, for some codes it is not legal to do dedicated heating with a water heater that is NOT doing DHW).
• You’ll want something a little more upscale than a standard water heater when you’re using 35kBTUs per hour of energy.
• Design for Rockport Mechanical in the picturesque town of Rockport, Maine was done by Rob Brown.

You could use an electric boiler, which has inputs as low as 1000 watts and can heat a large amount of water (1 KW).

Some electric boilers have pump relays built right into the unit, and some even have outdoor resets to save even more money.

However, they are significantly less expensive to purchase and install, and they would most likely only represent a minor blip on the electrical bill if the load is insignificant.

Having said that, I believe that smaller condensing modulating gas boilers are something that North America could use more of.

These are the next two smallest units: the IBC VFC 15-150 (wall mount), which modulates from 15,000 to 150,000 BTUH, and the Triange Tube, which modulates from 16,000 to 60,000 BTUH (also wall mount).

Having a boiler that modulates up to 30,000 would be extremely useful in a variety of applications ranging from boiler back up to small loads to someone who simply wants the redundancy of two boilers instead of one larger one with a higher turn down ratio, to name a few.

Journeyman Gas Fitter (Class ‘A’) – Certified Hydronic Systems Designer (CHD) Plumber 0;sThanks Vielen Dank to you and your colleagues for all of your help.

is a professional photographer based in New York.

Find the source of your itch because you have a rare opportunity.

0;sefficiency A water heater’s efficiency is calculated based on its intended use (dhw); it also takes into account standby losses, cycling time and stack losses, none of which are appropriate for a heater being used as a boiler, especially when installed in and with its chimney in a heated space and running continuously jc 0; Then there’s YOUR point.

• ME As opposed to “You got what you paid for,” it is more of a case of “You DIDN’T get what you DIDN’T pay for, and you are NOT going to get what you thought you were going to get in terms of comfort”.
• 0; Do not all of us have experience using a water heater to complete a minor radiant job?
• There’s also no reason to combine the two loads when determining the appropriate size of the water heater for your needs.
• Use your common sense as well, please.
• 0; Thank you for reaching out to me.
• The usual 66 percent vs.
• jc 0; What I’m saying is, I see your point.

In other words, if a water heater’s instantaneous efficiency is 80 percent, it can’t have an annual fuel utilization efficiency (AFUE) of more than 80 percent, correct?

Your response has been received with gratitude 🙂 ME As opposed to “You got what you paid for,” it is more of a case of “You DIDN’T receive what you DIDN’T pay for, and you are NOT going to get what you thought you were going to get in terms of comfort”.

0; The true statistics are beyond my comprehension, and I have no clue what instantaneous thermal efficiency is.

Just know that the figures commonly cited are the result of various testing techniques and are not useful in judging which heating unit would be more cost-effective than another.

Yes, I have utilized a water heater for a very tiny radiant load on a few of occasions in my career.

Approximately 10,000 btu’s were drawn from the load.

The radiant was created using a flat plate, and the domestic was created using a space heater.

He utilized 35,000 btu’s in his article, according to him.

Approximately 35,000 BTUs of heat are lost from my 2,000 square foot home.

Considering how inexpensive water heaters are, I see no reason why he couldn’t utilize one to temporarily heat his home while saving money to get a modern air conditioning system.

Greetings and best wishes for the New Year A bad installation leaves a bitter taste in the mouth that is far longer lasting than a cheap price with a pleasant taste in it.

The fact that a piece of equipment generates energy at a specific AFUE is impressive; but, what you do with the energy that you just paid to generate has a far greater influence on your fuel cost.

In order to avoid using them, here are a couple of my justifications: An electric water heater will produce the same quantity of btu’s on a daily basis, regardless of the temperature outside, which might cause a structure’s heat loss to vary.

Due to the nature of my water heater, I am left with attempting to make use of btu’s that I really didn’t need to be produced in the first place!

To spend part of the money I’d been attempting to save, I’ve done this.

Zero; Chris, I agree with all of your concerns, however the first, system design, makes an enormous dent in the final, standby loss, because the heater loses very little heat during the cold season if it and the vent are maintained in a warm location during the cold season.

jc 0; Want to get rid of some discomfort?

To begin, you have the improper curve set up on your computer.

I can see why you feel you have no other option than to manually reset the system.

A bad installation leaves a bitter taste in the mouth that is far longer lasting than a cheap price with a pleasant taste in it.

Whenever a customer comes to me with a request to heat a room, I’m tempted to recommend a combined water heater for practically any size under 1,000 square feet, especially if there are many zones to heat.

Despite being frequently incorrect, there is never a question.

The Wizard has correctly predicted the outcome.

35 thousand British thermal units The Lochinvar WB-050 was acquired with the help of a 30 percent tax credit and $500 utility refund.

As with the previous year, the team was three weeks behind schedule.

This is especially true if there is a lot of solar heat gain in the environment.

Over the course of 10 years, though, I never got chilly.

Send me an email letting me know how that little Knight wall mount works out for you.

foot rancher in a suburb of Vancouver, BC).

Journeyman Plumber – Certified Hydronic Systems Designer – Class ‘A’ Gas Fitter – Certified Hydronic Systems Designer In addition to the balancing valves, Chris, the only controls I have are the manual temperature adjustment on the heater and a line voltage thermostat on the pump.

If you have a 0 and you can do everything you want, it is a positive.

A somebody of your quality, I would expect you to provide them with options and your best professional advice.

One of My Points is a zero.

A bad installation leaves a bitter taste in the mouth that is far longer lasting than a cheap price with a pleasant taste in it. 0, which means that I am in total command. It’s simply that it doesn’t happen automatically, Chris. 0;

How Big Of A Water Heater Do I Need For Radiant Heat? – homedude

The most recent revision homedude is made possible by donations from readers. If you make a purchase after clicking on one of our affiliate links, we may receive a commission. More information may be found here. For many households in recent years, using a water heater to generate radiant heat has proven to be a more cost-effective, energy-efficient, and ecologically friendly choice. When using radiant heat, how much of a water heater do I need? The exact size of the water heater you require will be determined by your normal water use.

Homes with two to three occupants will require a 40-gallon tank, while homes with four or more occupants will require a tank with a minimum capacity of 50 gal.

However, the size of your home is not the only factor to consider when determining the size of the water heater you will require for radiant heat.

How Do Water Heaters Work?

An electric water heater works by allowing cold water to enter the tank by a dip tube, and then heating the water with electric heating components contained within the tank. By using the heat-out pipe, the hot water stored in the tank is distributed throughout the house.

Benefits Of Using Water Heaters

Many people are switching from boilers to water heaters, and this isn’t only because they are less expensive and easier to maintain in the long run. Using it for radiant floor heat also eliminates the need for frequent maintenance because water heaters are capable of operating for long periods of time without developing any serious difficulties. You may rest confident that water heaters, which are more efficient than boilers, will typically provide a greater heating performance. In addition, they help you save money on your energy expenses.

• Another group appears to be concerned about the system’s overall security.
• As an alternative to employing a water heater for radiant heating, you may construct a system that serves two functions at the same time, a practice known as a combination system, to accomplish two tasks at once.
• The need to purchase two separate heat pumps for your diverse family water heating requirements is eliminated, resulting in you receiving two heating pumps for the price of one and conserving valuable space at the same time.
• This is due to the fact that the heater would be able to maintain higher temperatures while acting as a radiant heater.

In order to solve this problem, you may install an automated mixing valve, which mixes hot and cold water and can be programmed to the necessary water temperature required for household hot water usage.

What Size Should My Hot Water Heater Be?

Source:Radovan1 Apart from the size of your family, there are a few additional elements to consider when answering the question: what size water heater do I require for radiant heat?

Fuel Source

It is critical to choose your preferred fuel source in order to cut down your alternatives and streamline your buying experience. For example, what kind of electricity do you want to use to power the hot water heater? Is it more cost-effective for you to use electricity, liquid propane, or natural gas as your fuel?

Physical Size of Water Heater

Consider the amount of room you have in your home. Despite the fact that a large hot water heater is ideal for large families, it will be of little use if it cannot be accommodated in the available area. You will either need to build additional space for the water heater or find a means to reduce your consumption of hot water.

BTU Output

In the event that you choose to go with a simple, low-cost system that does not include a heat exchanger, you can use any ordinary water heater as long as the BTU output is sufficient to handle the heating demand. It is important to note that the BTU is an abbreviation for British Thermal Unit, which is the usual means of calculating how much heat production is necessary to keep a room warm. If your heater’s BTU output is insufficient, it will not be able to fulfill its intended goal of producing radiant heat to your room.

• Consider installing a high-end sealed-combustion water heater with an exterior heat exchanger if you want to construct a more sophisticated heat-exchange system in your home or business.
• Generally speaking, the water heater should only be used for heating loads with a maximum output of 75,000 BTUh, according to the manufacturer (British Thermal Unit per hour).
• In dwellings with inadequate insulation, this figure might reach 40 BTU.
• Following that, you must ensure that the capacity of the water heater you select is sufficient for the heating job at hand.

Disadvantages Of Water Heaters For Radiant Heat

As previously said, there are several advantages to using a water heater. They are cost-effective, take up little space, and may be used for several purposes. However, what exactly are the drawbacks to utilizing water heaters for radiant heating?

Very slow to pick up when cool

When water is allowed to cold, water heaters take a long time to heat up and begin supplying radiant heat when the water is turned on. If you want it to continue to provide consistent warmth, the solution is to leave it on practically constantly.

Using heaters for radiant heat can void the heater’s warranty

Using a heater for radiant heating may violate the manufacturer’s warranty on the heater in question.

The use of a water heater for radiant heating, according to some manufacturers, affects the efficiency of the device. However, this is not true for all heaters.

Heaters can’t maintain very high temperatures (140°F) for long periods without wearing out easily

It is exceedingly unsafe to keep water above 120°F for any length of time, as water at that temperature is already extremely hot. While the heater is capable of maintaining water temperatures as high as 170°F, maintaining water temperatures above 140°F will cause your heater to wear out far more quickly.

Final Thoughts

It is exceedingly unsafe to experiment with water at temperatures higher than 120°F since water at that temperature is already dangerously hot. Water temperatures as high as 170°F can be maintained by the heater; however, maintaining water temperatures over 140°F will cause the heater to wear out much more quickly.

Frequently Asked Questions

It is exceedingly unsafe to keep water above 120°F for any length of time since water at that temperature is already extremely hot. While the heater is capable of maintaining water temperatures as high as 170°F, maintaining water temperatures above 140°F will cause the heater to wear out far more quickly.

Green Building Forums on Insulating Concrete Forms (ICF), Structural Insulated Panels (SIP), Radiant Heating, Geothermal Heat Pumps, Solar Power, Green Construction Projects

	Forums	Topics	Replies	Last Post
	Insulating Concrete Forms (ICFs)Discussions related to building and working with ICFs.	2686	27029	RE: Supplierby2bornot2b 23 Feb 2022 08:19 PM
	Structural Insulated Panels (SIPs)Discussions related to building and working with SIPs.	1387	12586	RE: SIPs – What should I.byrp_ho 13 Feb 2022 10:13 PM
	Radiant HeatingDiscussions related to buying and working with Radiant Heating.	1339	12873	RE: Heat Source choice fo.bysailawayrb 11 Feb 2022 01:50 AM
	Geothermal Heat PumpsDiscussions related to buying and working with Geothermal Heat Pumps.	2270	30225	RE: Is Geothermal right f.bysailawayrb 16 Feb 2022 11:52 PM
	Solar and Wind PowerDiscussions related to utilizing Solar and Wind Power for the home or building.	415	2621	RE: Schneider Conext Insi.bysailawayrb 05 Jan 2022 07:49 PM
	Windows/Doors and Interior/Exterior FinishDiscussions related to energy efficient windows/doors, siding, millwork, paint/coatings and other interior/exterior products for the home or building.	451	3734	RE: Doors and WindowsbyMack56M 23 Dec 2021 06:10 AM
	Appliances, Lighting and Kitchen/Bath FixturesDiscussions related to energy efficient appliances and indoor fixtures, including lighting, kitchen and bath.	147	1400	RE: High volume outdoor c.bynewbostonconst 17 Sep 2021 10:28 AM

Water Heater vs Boiler: Which Radiant Floor Option Is Best?

An increasing number of customers are curious about the type of heater they will require for their hydronic radiant floor heating system. The difficulty is that there are much too many variables to provide a satisfactory response. In some instances, a boiler is the sole solution, and only a boiler will suffice. In other situations, a water heater will almost likely be more efficient than a boiler, and it will also be more convenient. In yet another instance, the proper tankless water heater is ideal for radiant floor heating since it only warms the water when it is needed and delivers it swiftly, hence reducing energy consumption.

As a result of this post, you will have a better understanding of how each alternative should work for your radiant floor heating system and under what conditions, and you will be able to choose the one that is most suited for your needs.

Boiler vs Water Heater for Radiant Heat

An increasing number of individuals are curious about what type of heater they will require for their hydronic radiant floor heating system. Because there are so many factors, there is no way to provide a flawless solution. It may be necessary to use simply a boiler in some circumstances. In other situations, a water heater will almost likely be more efficient than a boiler, and it will also be less expensive. Other times, a tankless water heater is ideal for radiant floor heating since it only warms the water when it is needed and delivers it swiftly, allowing you to save time and money.

As a result of this post, you will have a better understanding of how each alternative should perform for your radiant floor heating system and under what conditions, and you will be able to choose the one that is most suited for your situation.

• Hot water heater– A hot water heater is a device that provides household hot water to your appliances such as dishwashers and washing machines, as well as fixtures such as showers and sinks, among other things. Tank or tankless models are available, as well as gas or electric models. As it boils and transforms into steam, a boiler is used to heat just one fluid at a time
• Water is employed in this process. These are for closed systems, which are commonly referred to as hydronic systems, and they are only used for heating. Alternatively, they can be utilized in conjunction with radiators or radiant floor heating

Another version, known as the acombi waterheater, is capable of performing both functions. It is constructed in such a way that different zones can be utilized. You may use hot water to heat your home’s heating system, such as an in-floor heater, or to wash your hands with it. So, which one do you need for radiant floor heating, and how do you get it? It is possible to utilize a water heater or a tankless system for radiant floor heating rather than merely a boiler, so you have an option between the two.

Radiant Floor Heating Water Heater

Water heaters are ideal for radiant floor heating systems because they keep the temperature at a consistent low level. Radiant heat floors only require a maximum temperature of 120°F to function properly. That temperature is both safe and comfortable, as well as being effective in terms of energy efficiency. You will need to be conscious of the temperature of the incoming groundwater since cold water will cause the total water temperature to decrease. When utilizing a water heater that produces water that is cooler than 55°F, it may take a bit longer for the radiant heating system to warm up.

When you are not attempting to heat many zones at the same time, a water heater will function properly.

When using a water heater, it is preferable to have a single zone that maintains the same temperature throughout the whole house.

What Water Heater is Good for Radiant Floor Heat?

High-efficiency radiant floor heating should be used in conjunction with your radiant floor heating system. The optimum kind is one that features a sealed combustion chamber as well as an exterior heat exchanger for maximum efficiency. The rationale for this is to keep the two types of water usage distinct. Water will stagnate in the water heater floor during the summer, and if this water is mixed with your ordinary water, it will be harmful. When water remains in pipes for an extended period of time, it can cause Legionnaires’ disease.

Set a timer on your hot water circulating pump to run for 10 minutes every day to flush away any stagnant water.

Alternatively, if you do not want to update your water heater, you may install an exterior heat exchanger.

Electric Water Heaters for Hydronic Floor Heating

High-efficiency radiant floor heating should be used in conjunction with the radiant floor heating system. It is preferable to use a unit that has a sealed combustion chamber as well as an external heat exchanger. In order to keep the two water usage distinct, this is necessary. The water heater floor will stagnate in the summer, and if this water is mixed with your ordinary water, it will be harmful to you and your family. When water remains in pipes for an extended period of time, the risk of Legionnaires’ disease increases.

Set a timer on your hot water circulating pump to run for 10 minutes every day to flush away any stagnant water.

This will help you prevent this problem in the future. Alternatively, if you do not like to improve your water heater, you can install an exterior heat exchanger. To prevent the water from mixing with your domestic water, you’ll just need to run a loop from that point back to your hot water heater.

• Permaglas glass covering prevents steel tanks from corrosion while increasing their efficiency. The Dynaclean diffuser dip tube aids in the reduction of lime and sediment accumulation, while also: The tank is protected by the CoreGard anode rod, which is made of aluminum with a stainless steel core. Brass drain valve that is long-lasting and tamper-resistant
• It complies with all current rules established by the National Appliance Energy

One important caution to keep in mind is that many water heater manufacturers may invalidate the warranty if the water heater is used as an infloor heater. Despite the fact that they may be used well for radiant floor heating, this was not their primary use. An further consideration is that they typically lack the BTU capacity to simultaneously heat a large house and provide domestic water. If you simply want one zone and not the entire house, then they will enough for your needs. You’ll also need an expansion tank for when the hot water starts to heat up, so that it doesn’t overflow the pressure release valve when the water is turned off.

The expanding hot water will not have anywhere to go because it is in a closed loop, thus the expansion tank is required to provide a release for the expanding hot water.

• Defends your heating systems by preventing dangerous pressure buildup. A solid carbon steel frame is used in conjunction with an exclusive polypropylene material. A Factory Leak Test and NSF61 Certification are performed on each tank. The maximum operating pressure is 75 PSI, and the maximum temperature is 210°F. The use of a low-profile tank design with a full membrane depth eliminates the need to stretch

Defends your heating systems by preventing dangerous pressure buildup; A solid carbon steel frame is used in conjunction with an exclusive polypropylene material to create this product. A Factory Leak Test and NSF61 Certification are performed on every tank. Temperature of 210°F and maximum operating pressure of 75 PSI. Because of the low profile tank design and full membrane depth, stretching of the membrane is eliminated.

• TLC stands for Timer, Line Cord, and 6-Foot
• A range of 0 to 9 US GPM and a height of 0 to 6-feet are available. Motors are single phase and operate at 115V. Provisional supply voltages of 115-120 VAC at 60 hertz are available
• The connection is 3/4-Inch M by 3/4-Inch FNPT. Maintenance-free and energy-efficient
• The Grundfos circulator pumps of the Series UP are especially intended for the following applications:

The use of an existing hot water circulation pump that does not have a timer means that it is not necessary to replace the pump. Instead, you may use this Taco Smart Plug to regulate when the pump should be turned on. It even keeps track of your water consumption habits so you know when you’re most in need of water. Sale

Boiler for Radiant Heating Systems

Because a boiler only has one function, which is to provide heat in a hydronic system, they are suitable for the job. Many individuals are opposed to the usage of boilers since it necessitates the installation of two systems. One for the heating system and another for the usage of domestic water for things like appliances and plumbing fittings. The fact is that they were developed specifically for this function and will be covered by a complete guarantee if anything goes wrong because they are not being asked to do a task for which they were not intended.

Why?

A condensing boiler will emit exhaust through a flue at a temperature of around 60°F, making it cold enough to vent using PVC.

The Rinnai Condensing Boiler, shown below, is a small, energy-efficient unit that is an excellent alternative for your radiant floor heating system.

• Hot Water Heater: This boiler, which has a fully enclosed design, can heat the entire house. Smart Features: This smart heater has spark ignition technology as well as an easy-to-use interface. The operation is extremely quiet, allowing for convenience and comfort. make the necessary adjustments
• Design that saves space: The compact wall-mounted design of this water heater saves space. Guaranteed to Last: 12-, 5-, and 1-year residential warranties, as well as 12-, 2-, and 1-year commercial warranties

A boiler will be required if you want to install radiant floor heating in a garage that can get extremely cold while not in use or if you want to heat a driveway since you will need to use antifreeze fluid mixed with the water.

Combi Boilers for Radiant Heat

Acombi boilercombines the finest of both worlds and is the method I recommend for heating your house while also meeting your domestic water demands. They are intended to perform well in all roles, and they are extremely energy efficient, making them perfect for radiant floor heating systems. The fact that they are little makes the installation process simpler, as you have more alternatives for where to place them. They are extremely energy efficient since they operate in a manner similar to tankless water heaters, delivering hot water rapidly and without a significant amount of heat loss.

Furthermore, because the majority of them come with a built-in circulating pump, they save you money on that as well as time during installation.

Rinnai Combi Boiler (Rinnai Combi Boiler)

• Hot Water Heater: This boiler, which includes a
• Allows you to heat the entire house. Smart Features: The capacity to operate many zones with a single thermostat
• Interface that is user-friendly: The major feature of the electric heater is a digital display. Design that saves space: The compact wall-mounted design of this water heater saves space. Homeownership guarantees of 12, 2, and 1-year terms, as well as commercial guarantees of 5, 2, and 1-year terms.

Noritz Combi Boiler is a type of boiler that has a number of functions.

• A Combi Boiler from Noritz is a type of boiler that combines both heating and cooking functions.

Tankless Water Heater for Radiant Floor Heating

Tankless water heaters are becoming increasingly popular as a means of supplying radiant floor heating systems as well as residential water demands. In addition to taking up very little space, they are incredibly efficient and can run at temperatures that are lower than those required by a standard boiler without generating hazardous condensation. One significant disadvantage, however, is that when you are heating your floor, the tankless will be running continuously for the duration of the heating cycle.

If you want to use radiant floor heating, look for a tankless water heater with an energy efficiency rating of at least 90.

There are natural gas and propane tankless water heaters available, so you should be able to locate one that works with your preferred fuel.

Best Electric Water Heater for Radiant Floor Heat

If you decide to go with an electric tankless water heater, you have a few different alternatives to select from. The Rheem RTEX-18 is the one that we prefer the most. It has a very high energy efficiency rating, which means it will save you money in the long term on your energy bills. A thermostat that is separate from the unit and works in conjunction with the LED screen is also included. A family of two or three people would benefit most from the modest flow rate of 4.4 GPM. For more information on sizing your tankless, please visit this page.

• (+1 degree Celsius) Digital thermostatic control with LED display on the outside of the unit. Self-modulation technology is the most advanced available, adjusting power to match hot water demand. Copper immersion heater with two heating components that may be serviced in the field. Flow
• Installation is straightforward: 3/4 inch NPT water connections are used at the bottom. Threaded for easy repair, simple installation, and digital temperature readings are all available.

Best Overall Water Heater for Radiant Floor Heat

Control of an external digital thermostat with an LED display (+1 degree Celsius). Power is adjusted to fulfill hot water demand using the most sophisticated self-modulation. Copper immersion heater with two heating elements that may be serviced in the field. Durable. Flow; Water connections at the bottom are 3/4 inch NPT, making installation straightforward. Threaded for easy repair, simple installation, and digital temperature readings are available.

• (+1 degree Celsius) Digital thermostatic control with LED display on the outside of the enclosure. Self-modulation technology is the most advanced available, adjusting power to match hot water demand
• Copper immersion heater with two heating components that are field serviceable. Flow
• Installation is straightforward: 3/4-inch NPT water connections are used at the bottom. Threaded for quick replacement, simple installation, and digital temperature

External digital thermostatic control with LED display (+/-1 degree); The most advanced self-modulation technology, which adjusts electricity to match hot water demand; Copper immersion heaters with two heating components that are field serviceable. Flow; Installation is straightforward: 3/4 inch NPT water connections are used at the bottom of the tank. Threaded for quick replacement, simple installation, digital temperature;

How Big of a Water Heater Do I Need for Radiant Heat

(+1 degree Celsius) Digital thermostatic control with LED display on the outside of the unit. Self-modulation technology is the most advanced available, adjusting power to match hot water demand. Copper immersion heater with two heating components that may be serviced in the field. Flow; Installation is straightforward: 3/4 inch NPT water connections are used at the bottom. Threaded for easy repair, simple installation, and digital temperature readings are all available.

Room Type	Load Factors (BTU/hr/sq.ft)	Qty	Total for Fixture Type
			0 BTU
			0 BTU
			0 BTU
			0 BTU
			0 BTU
			0 BTU
Total Load Factors	0 BTU

Simply enter the number of areas you require heating and the calculator will calculate the load factors for you. This will provide you with the BTU/hour that you require in order to establish the size of your water heater or boiler that you require. In the event that your demands exceed 60,000 BTU/hour, you should consider a high GPM tankless system or purchasing additional boilers.

Is it Legal to use a Water Heater for Radiant Heat?

Check with your local building department to see whether you may use a water heater instead of a boiler as the energy source for your hydronic radiant floor before making a selection. In other places, such as Michigan, you are unable to do so. Any heater that is intended for space heating must be clearly labeled as such, and it cannot be used to provide domestic hot water. In order to prevent legionnaires disease in some areas, a closed loop system is required. If you utilize a water heater as a boiler in a location where it is legal to do so, many manufacturers may refuse to honor your guarantee if something goes wrong while you are using it as a boiler in that location.

Conclusion

After reading this article on the differences between water heaters and boilers for radiant floor heating systems, you should have a better understanding of what you require. Despite the fact that there are many different types of radiant floor heating systems, boilers and water heaters are both effective. The selection of the most appropriate hydronic radiant floor heating system is difficult since there are so many elements to consider, including the selection of the most appropriate radiant heat insulation.

ImageImageImageImageImageImageImageImageImageImageImageImageImageImageImageImageImageImageImage Nick Lopresti is the creator of YourH2Home and a well-known specialist in the field of home renovation.

Sizing heat source for radiant floor heat

A conventional 40-gallon gas hot water heater is capable of providing enough heat for a radiant floor heat system, but is this sufficient? Details: 1200 sq ft 1-story on slab, about 8-10 years old We reside in a northern latitude (Montana), where we normally get at least a few weeks of the year with temperatures below zero (we live in a more temperate part of the state) The heat source is a Rheem natural gas 40 gallon hot water heater with an input rating of 38,000 BTU/HR. As an added bonus, this hot water heater (as well as the domestic hot water heater) are both located in an unconditioned external closet (with R-19 wall insulation) with an exterior exhaust for combustion air.

Furthermore, it appears to be a waste of energy to keep the 40-gallon tank at a constant temperature at all times.

Upon closer inspection, I can see 2″ rigid foam insulation installed on the exterior of the slab foundation; however, I am unsure of how deep down it reaches or what is beneath the slab.

When I do come across a radiant floor heat system, it is almost always powered by a gas boiler system with at LEAST 90-100,000 BTUs of output power.

Ordinarily, I refrain from commenting on the sizing of heating systems unless the system is visibly inadequate. However, even to me, this appears to be a little ‘on the cheap.’ Fortunately, the buyer has already decided to purchase and install a wood stove. TerrySimilar Discussions:

• Examining for asbestos floor tiles is not simple – Mortage 101. Heat Pumps and air conditioning fuel sources are also recalled by the Consumer Product Safety Commission.

Re: Sizing heat source for radiant floor heat

• There are numerous variables that come into play, and I don’t believe there is a definitive answer other than to state that you will not know unless a heat loss calculation is performed. Variables that will have an impact on the amount of heat produced. 1. Insulation levels are high. 2. the placement and siting of the building 3. the total number of storylines
• 4. the total number of loops 5. the depth of the loops in the slab
• 6. the temperatures of the water entering and leaving the slab. temperature setting9. amount of windows/shading10. whether or if the slab is insulated

Re: Sizing heat source for radiant floor heat

• You have just answered your own question: normally, you see 90-100,000 BTU/hr, however this one is delivering 38,000 BTU/hr and is on continually. When the temperature goes below a certain level or the wind picks up, the party is finished. Perhaps they will just put another heater in a serial fashion next to it.

Re: Sizing heat source for radiant floor heat

• In comparison to tanks with burners designed to heat and hold water over time, boilers are more efficient in heating water. The temperature of the household potable water is typically 125 degrees Fahrenheit, whereas the temperature of the floor heating is often 100 to 105 degrees Fahrenheit. A boiler with a separate circulation and intelligent management may fire at a lower rate to deliver warm water for the floor as needed, then ramp up to fire at full blast to supply potable hot water as needed, all while operating at peak efficiency and with little energy use. An indirect tank boiler with smart management would be a far superior answer, especially in a cold area, I would wager, but I would defer to radiant heat specialists such as Mark Eatherton in Colorado for further information on this topic. To really go all out, invest in a modulating condensing boiler with many zones and a sophisticated controller. Bob Maintain the flames in the fireplace

Re: Sizing heat source for radiant floor heat

• What a shambles! Approximately 50% of all water heaters are not intended for use as a space heater. It is necessary to check your T P valve, which should be adjusted at 30 PSI and 120 F. There are too many more code infractions to name them all.

Re: Sizing heat source for radiant floor heat

• That is a complete and utter disaster. Space heating is not specified on about half of the water heaters. T P valves should be adjusted at 30 PSI and 120 degrees Fahrenheit, respectively. In addition, there are just too many more code infractions to mention.

Re: Sizing heat source for radiant floor heat

• You should be able to heat it with a water heater unless it has been freezing for the previous ten years in a row. I agree that it is not going to be a really effective system, and that it will most likely struggle to keep up with the low temperatures you will be experiencing. The fact that your furnace is running consistently at its highest thermostat setting in March is not a good indication at all. A few years ago, there was an excellent piece in Fine Homebuilding or JLC about a guy in Montana who heated his house (in floor radiant) using a tankless water heater and saved money on energy costs. He stated that it was excellent. If it were up to me, I’d probably have a look at anything along those lines. ‘Jim Robinson’ is a fictional character created by Jim Robinson. New Mexico, United States of America

Re: Sizing heat source for radiant floor heat

• It appears that the system is not up to the task. You’ll need to figure out how much heat is being lost in BTUs. Whatever figure you come up with, that will be the smallest size heating source you will require for your project. Whatever you come up with should be rounded up to the next sized unit (ie., 35000 – 3700 BTU loss replace it with a 40000 BTU unit). An undersized unit will operate continuously, whereas an oversized unit would operate intermittently (too much over sized will cycle on and off too often). In either case, you will damage the unit by causing it to start and shut down too frequently, or it will run continuously, producing excessive wear on the system. Best of luck

Re: Sizing heat source for radiant floor heat

1. Just the fact that the heater is set at the maximum level all of the time is a source of irritation. 1) The heater is unable to keep up with the increased demand. 2) Even if it did meet the requirements, the water stored in the tank would be too hot for the system as it is now configured. In fact, there are on-demand tankless systems that would deliver superior results with minimum modification to the pipes and would be be less than the 40-gallon tank.

Posting Permissions

• You are not permitted to start new posts or reply to existing ones. You are not permitted to submit attachments. You are not permitted to modify your posts.

The Rules of the Forum

Heat loss calcs, and how to size a water heater for hydronic heating

Hi, We are constructing a home in Central Oregon that will be heated by slab hydronics, and our HVAC contractor has recommended that we use two electric water heaters to handle the demand (no gas avail). He estimates that our need will be around 52kBTU/hr when the temperature outside is 0 degrees Fahrenheit and the slab is heated to 70 degrees Fahrenheit. As a result, two 50-gallon water heaters rated at 30kBTU each are sufficient as a buffer. He claims to have used Wrightsoft Manual J to do the calculations.

• I understand that the 2000 sqft house is meant to be somewhat small; does this demand sound realistic (notwithstanding all of the debates over the advisability of employing hydronic heating in small homes)?
• my assumptions are as follows: 70 degrees Fahrenheit inside, 0 degrees Fahrenheit outside, ground temperature beneath slab 50 degrees Celsius windows: 450 square feet on average, U=0.28 Q is equal to 8000 BTU/hr.
• Q= 11 kBTU/hr (thermal capacity) Stem walls: 195 feet in circumference, U=0.83, with the top 2 inches in touch with the slab.
• The slab is 1360 square feet with R22 below it and a ground temperature of 50 degrees.
• I’ll get to the TBD’s later in my model, but even if they add up to 4000 BTU/hr, it won’t push my total estimations much higher than 26kBTU/hr, which is still within reasonable limits.
• thanks, bob

GBA Detail Library

Building details categorized by climate and home component in a collection of one thousand construction details Construction specifications may be found and downloaded.