How Hard Is It To Install A Tankless Water Heater

How Hard Is It To Install a Tankless Water Heater?

Briefly stated, the answer is dependent on the brand and kind of tankless water heater that you choose. Several factors influence the complexity of installation, including the clarity of the manufacturer’s installation instructions and the type of existing venting in your property, among others. However, the question is not whether or not it is necessary to install a tankless water heater, but whether or not you should do so. It’s not possible to answer that question. The number of people who have successfully installed a tankless water heater themselves is growing, but manufacturers strongly advise purchasers not to do it themselves.

Suppose a tankless water heater fueled by natural gas is not correctly connected to its natural gas supply line.

In the same way, if the existing

The Realities of Installing a Tankless Water Heater

Many people believe that tankless water heaters are the type that can be installed in minutes. It is simply not possible to replace your old tank-style water heater with a tankless water heater. Tankless water heaters are not often placed in a home with tankless retrofitting in mind, as is the case with regular gas-powered water heaters. You should consider whether or not your home’s current gas line (as well as its gas meter and associated plumbing) is adequately designed to accommodate the increased demand for gas that a tankless water heater would generate.

Many homeowners who are dissatisfied with their tankless water heaters typically have one of the following problems:


Before and after the installation of a tankless water heater, many cities and municipalities now need licenses to be acquired and inspections to be carried out before and after the installation. Electrical permissions, gas pipeline permits, and mechanical permits are just a handful of the licenses that may be required for a construction project. The criteria will vary based on where you live and in what jurisdiction you reside. In order for a normal 40-gallon water heater with a storage tank to work, it must be supplied with 40,000 BTUs per hour of energy.

The amount of carbon monoxide and exhaust emissions produced by each type of water heater, as well as the amount of venting required, is radically different.


Read lots of tankless water heater reviews before making the decision to go with a tankless water heater. Get quotations from a variety of specialists to evaluate who offers the greatest value, and don’t forget to verify each professional’s internet references and reviews to be sure they’re a good fit. Find out how much it will cost to upgrade your home’s present venting, electrical system, and gas fittings.

Just because you believe you are capable of installing your new tankless heater on your own does not mean you have do. It is not worth jeopardizing your health and safety in order to save a few dollars.

Thinking of upgrading to a tankless water heater? Before doing so, learn the pros and cons of installing one

Are you considering making the switch to a tankless water heater? Before doing so, educate yourself about the advantages and disadvantages of installing one, including the cost, needs, and upkeep. It is possible that you are considering installing a tankless water heater in your house if it is time to replace your current water heater. We’ll explain how tankless water heaters function and point out some of its pros and downsides to assist you in making the best decision about which kind to install.

Do you require an expert right away?

To make a reservation, please click here.

The services available differ depending on the market.

How Tankless Water Heaters Work

Known variously as demand type, on-demand, or instantaneous water heaters, these appliances heat water directly, eliminating the need to store water. A flow detecting device is installed in a tankless heater, and it is triggered anytime the hot water tap is opened. A gas burner or an electric element is used to heat the water, which is then sent to the various locations in your home where it is needed. You won’t have to worry about running out of hot water because there isn’t a tank that has to be filled.

Advantages Of Tankless Water Heaters

  • They are more compact than typical storage heaters, are wall-mounted, and do not take up any floor space when not in use. As a result of their size, they can be particularly appealing in houses where space is limited
  • They can also help you save money on your energy bills. According to the United States Department of Energy, heating water accounts for around 30% of a family’s total energy use. It is possible to save up to 50% on these expenditures by installing a tankless water heater, resulting in an average yearly savings of $80. Tankless water heaters are also more durable and less likely to malfunction, resulting in potentially disastrous flooding in your house. Compared to traditional water heaters, tankless systems have a lifespan that is about twice as long – 20 years or more.

Disadvantages Of Tankless Water Heaters

  • Tankless units are more costly than conventional units. It will cost around the same as a standard tank type to purchase an electric tankless heater, however a gas tankless heater would cost between $1,000 to $1,200. The national average for tankless unit installation is somewhat more than $1,700, which is in addition to the original cost of the unit. A safe vent must be created for a gas unit to prevent carbon monoxide from collecting within the property in many circumstances. Existing plumbing must also be expanded or moved in many cases. Tankless water heaters do not provide “instant hot water,” even when energy savings are taken into consideration
  • For many households, it will take around 20 years to completely return their expenditures. Contrary to common belief, a tankless water heater does not always provide hot water to your faucets and showers.

Gas or Electric

Electric tankless water heaters are significantly less expensive than their gas counterparts. Installation is less complicated and less expensive, and they are often less difficult to maintain than gas-powered ones. Only a few handful, however, have the capability of serving many locations at the same time. Gas units are available in a wide range of types and sizes for both residential and commercial applications, with outputs ranging from 130,000 to 380,000 BTUs in certain cases. More BTUs equate to more heating capacity.

As a result, your home’s gas pipe, meter, and main line to the meter may not be correctly proportioned, necessitating a costly reconfiguration and installation of new equipment.


Water Heater Protection

Whatever method you use to fulfill your household’s hot water requirements, you’ll want to make sure that the investment you’ve made in your water heater is protected. That entails completing the preventative water heater maintenance advised by the manufacturer, as well as routinely emptying the tank (or lines) to remove potentially harmful silt and scale. Consider obtaining an American Home Shield® Water Heater Home Warranty to help reduce the expenses involved with the repair and replacement of your water heater even more.

It is particularly stated that AHS takes no responsibility, and expressly disclaims all liability, in connection with your use of any and all material included on this website. NO TWO HOUSEHOLDS ARE IDENTICAL. WE HAVE OPTIONS BECAUSE WE CARE. DISCOVER A PLAN THAT WORKS FOR YOU.

How to Install or Replace a Tankless Water Heater

Despite the fact that it’s a tankless job, someone has to do it. Leaving aside the dad jokes, installing a tankless water heater is a serious undertaking that should be approached with caution. Our goal is to make this process as simple and pleasant as possible, so we’ve included step-by-step instructions for both gas and electric units below. Take note that replacing a tankless water heater is a time-consuming process requiring advanced technical knowledge. So, if you aren’t confident in your plumbing and electrical abilities, it is preferable to engage a licensed professional – in certain areas, this is a legal requirement.

How to Install a Gas Tankless Water Heater

Installation and replacement of tankless water heaters may be quite expensive, as we realize. Installing your own unit is doable, but we recommend that you proceed with caution. This should only be attempted if you have extensive experience working with gas lines, water lines, and electrical systems. Installing your tankless water heater incorrectly might result in significant harm to your home. Unsafe gas line installation may cause explosions, while faulty gas venting can result in deadly carbon dioxide leaking into your house.

If you are considering a do-it-yourself installation, it is critical that you understand the terms of your insurance policy.

Step 1

Depending on the manufacturer, if their systems are not installed by certified professionals, the warranty may be voided.

Step 2

Make certain that you obtain all necessary state or local permissions before installing or upgrading a water heater.

Step 3

For water pressure more than 80 psi, you’ll need to install a pressure-reducing valve upstream of the new water heater before it will work properly. When establishing the cold and hot water connections (as described in the section below under “Establish the cold and hot water connections”), you should consider whether or not you need to install one.

Step 4

  • Make sure you check your local construction codes to see where you may put your water heater in your home. These tankless gas systems must be vented directly to the outdoors, rather than through a chimney, in order to function properly. Consequently, it is vital to identify a position where the unit may readily vent outdoors while also complying with local code requirements for vent placement. Carefully review the manufacturer’s installation instructions to ensure that you have adequate clearance around the device
  • Stay away from locations where:
  • Temperatures below freezing might have an impact on the unit. Any form of liquid might be sprayed on the device on a regular basis. There is a significant amount of humidity and wetness

Step 5

Make careful to accurately measure the space where you intend to install the water heater to ensure that you acquire the appropriate-sized unit.

Step 6

  • Tankless gas water heaters consume more gas than traditional tank-style water heaters. Determine whether or not your present gas line will be sufficient initially
  • If not, upgrade it. A professional contractor will be required to install a newer, larger gas pipe if your present gas line is unable to keep up with the demand.

Step 7

  • If there isn’t a shut-off valve before the heater, cut off the main water supply
  • Otherwise, turn off the heater. Remove the heater from service by closing all power and gas supply valves to it. Disconnect the unit’s power
  • When dealing with hot water, utilize a hose that is designed to tolerate high temperatures. To relieve pressure in the system, open a hot water faucet for a few minutes. Allow it to completely drain
  • Ensure that the water heater is disconnected from the gas and water pipes. Make sure to properly dispose of your old water heater.
  • For information on how to properly dispose of it, contact your local recycling and/or sanitation agencies.

Step 8

  • Ensure that the device is properly supported by constructing a mounting box that is approximately four inches away from the wall. The foundation wall should be properly secured with appropriate anchors. Follow the manufacturer’s instructions for mounting the device to the box firmly.

Step 9

  • Hiring a professional contractor should be your first choice unless you have extensive knowledge with gas line installations. Utilize a threaded black iron pipe to connect the existing tee to the unit position if your present gas line is the suitable size and you can connect it without breaking the existing connection. Remember to switch off the main gas line before removing the down pipe from the previous unit if you’re replacing it. After ensuring that the gas line is routed to the right location, you should install a tee, a sediment trap, and a gas shut-off valve. The shutdown valve and sediment trap should be connected to the heater in accordance with the manufacturer’s instructions. Install a new gas supply line from the tee to a location where it can be conveniently connected to the gas line of the new unit. You can make use of a black pen.
See also:  How To Tell If Water Heater Element Is Burned Out

Step 10

  • Connecting the water heater valves to the water supply line should be done according to the manufacturer’s instructions.
  • Connecting new hot and cold water lines to existing water lines should be done with copper pipe. Continue to connect the wires to the new unit. It is possible that copper pipe will need to be cut and soldered to the unit.
  • Depending on whether your water system includes an anti-siphon valve or a check valve on the supply line, you may require an expansion tank close to the cold intake. More information can be found in your vehicle’s owner handbook. Bell hangers should be used to secure the pipe to the wall. Place the pressure relief valve in its proper location. Installing a purge valve and a pressure relief valve should be done according to the manufacturer’s instructions.

Step 11

  • Make sure there are no leaks by turning on the water supply. To check for leaks, turn on the gas and wait a few minutes. It is possible that you will need to bleed the line. Afterwards, switch off the gas supply until the installation is complete.

Step 12

  • When it comes to correctly venting the device, follow the manufacturer’s recommendations as a reference. There’s a considerable probability that you’ll be able to vent your water heater straight through the rim joists in your home. Only utilize pipes that have been specifically designed for this sort of venting. In some cases, depending on the manufacturer, you may require a vent kit. Make sure that the vent shaft of the new unit is sealed with a heat-resistant silicone sealant. Afterwards, attach a connection to it and secure it with an appropriate hose clamp
  • Place a length of stainless steel vent pipe on top of the structure. Put on a retaining ring to keep it in place. Folding over the tabs can help to keep it secure. Slip an elbow inside a pocket. Make sure that the aperture faces the direction in which the unit will vent to the outside
  • Select a spot on the joist or wall that will serve as the center of the venting system.

Step 13

  • To remove air from the water pipes and heater, turn on the faucet to its full “hot” setting. Close the water supply valve

Step 14

Connect the water heater to the wall outlet. That is all there is to it.

Step 15

The hot water line that originates from the water heater should be insulated.

Step 16

The gas should be turned on when the installation is complete. Your water heater should be up and running at this point!

How to Install an Electric Tankless Water Heater

Installation and replacement of tankless water heaters may be quite expensive, as we realize. Installing your own unit is doable, but we recommend that you proceed with caution. This should only be attempted if you have extensive experience working with water lines and electrical systems. Installing your tankless water heater incorrectly might result in significant harm to your home. If you are considering a do-it-yourself installation, it is critical that you understand the terms of your insurance policy.

You can install your unit yourself if you are confident in your abilities and have double-checked with your insurance company. The instructions below will guide you through the process.

Step 1

Depending on the manufacturer, if their systems are not installed by certified professionals, the warranty may be voided.

Step 2

Confirm that your electrical service panel has the capacity to manage the energy demands of an electric tankless water heater before installing one. It’s possible that you’ll need to upgrade your panel or install a whole new one. It is possible to uncover useful information by inspecting your electrical breaker box or the label on the electrical panel in your home. You might also consult with an electrician. The majority of suitable water heaters require a minimum of four 40AMP breakers to deliver hot water for a two and a half bath house.

Step 3

For water pressure more than 80 psi, you’ll need to install a pressure-reducing valve upstream of the new water heater before it will work properly. When establishing the cold and hot water connections (as described in the section below under “Establish the cold and hot water connections”), you should consider whether or not you need to install one.

Step 4

Make certain that you obtain all necessary state or local permissions before installing or upgrading a water heater.

Step 5

  • In order to heat water for the entire house, it is best to locate the unit closest to the area in which the majority of the hot water is consumed. If you’re installing a point-of-use system, try to locate them as near to the points of use as feasible. Always keep in mind that most electric tankless water heaters must be mounted vertically, with the water and electrical supply connections on the bottom of the unit. Follow the manufacturer’s recommendations for leaving a particular amount of clearance for service
  • In general, you want to stay away from locations where:
  • Temperatures below freezing might have an impact on the unit. Any form of liquid might be sprayed on the device on a regular basis. There is a significant amount of humidity and wetness

Step 6

Disconnect any circuit breakers that are connected to the new device. This is critically crucial!

Step 7

You don’t want your office to become a swamp!

Step 8

  • If there isn’t a shut-off valve before the heater, cut off the main water supply
  • Otherwise, turn off the heater. Remove the heater from service by closing all power and gas supply valves to it. Disconnect the unit’s power
  • When dealing with hot water, utilize a hose that is designed to tolerate high temperatures. To relieve pressure in the system, open a hot water faucet for a few minutes. Allow it to completely drain
  • Ensure that the water heater is disconnected from the gas and water pipes. Make sure to properly dispose of your old water heater.
  • For information on how to properly dispose of it, contact your local recycling and/or sanitation agencies.

Step 9

  • Remove any screws that are holding the front cover of the new device in place
  • And Please keep in mind that you may need to remove at least one plug before you can set it aside.

Step 10

A set of adequate anchors and screws should be included in the box.

Step 11

  • Connections for the cold and hot water should be made. The right side of the body is commonly affected by a cold.
  • The quickest and most straightforward method is to use stainless steel flex pipe with Teflon tape. You can also utilize copper tubing that has been rated for use in high-temperature environments. If you have to cut into a pipe, make sure the edges are clean. Before connecting the pipes to the water heater, flush them with water once they have been soldered. Also keep in mind that too much heat might cause harm to the water heater. If you want to do maintenance on your heater, it’s a good idea to install a shut-off valve before and after it. This will allow you to stop off the water supply to the unit without shutting off the water supply to the rest of your home
  • If you need to install a pressure reduction valve, you should do it immediately on the cold water side of the plumbing system. It is unlikely that you will require the installation of a temperature and pressure relief system.

Step 12

  • By opening various hot water outlets, you may remove any trapped air from the device and the pipes. While you’re waiting, you should inspect each and every connection for leaks.

Step 13

This step must not be skipped!

Step 14

  • Heater on one side, and electrical panel on the other, is the recommended arrangement
  • Comply with the manufacturer’s wiring diagram and their instructions for selecting the appropriate wire, circuit breaker number, and circuit breaker size
  • And Cutting and stripping every wire set to the proper length is followed by pushing them through the bottom holes of the new water heater’s housing. After that, connect the wires to the appropriate slots on the terminal block.
  • For the most appropriate torque, see the product handbook. It is important to remember that a ground conductor must be connected to the circuit breaker panel and the grounding busbar of the unit for each circuit.
  • Double-check that all of the electrical connections are in proper working order and that all of the wire sets have been appropriately installed.

Step 15

Make use of the screws that you already removed.

Step 16

The device should be turned on at this point. Select your chosen unit settings from the drop-down menu.

Step 17

Start by turning on the hot side of a faucet in your home. After the water temperature has steadied, take another reading. The temperature may be adjusted on the device itself if you desire to do so.

Learn More About Tankless Water Heaters

Right now, our plumbing professionals are here to take care of your repair needs. They’ll assess your situation, propose a solution at a reasonable fee up front, and then get to work!

Upfront Pricing

There are no hidden fees.

Quality Work

Guaranteed 100 percent customer satisfaction

24/7 Service


Water heater replacement: pros and cons of tankless water heaters

Tankless water heaters, also known as on-demand water heaters, are becoming increasingly popular among environmentally conscious households, and for good cause. A tankless water heater does not have a tank (thank you for asking). While a traditional tank water heater slowly heats water in a tank and maintains the temperature of that hot water, a tankless water heater only heats the water that is really needed, and it does it extremely rapidly. The vast majority of tankless water heaters on the market today are high-efficiency, direct-vent, powervent devices using powervent technology.

Because they are all so distinct, I have to talk in broad strokes for the sake of this blog article.

Benefits of a tankless water heater

The reduced size of a tankless water heater is one of the most evident advantages. In order to avoid taking up a large amount of floor area, tankless water heaters are typically installed on a wall. Another significant advantage is the virtually limitless supply of hot water. Shower for five hours and never run out of hot water is a reality for many people. For those who have access to a hot tub, you could fill the entire thing with hot water and be ready to utilize it as soon as the water is through filling it.

Tankless water heaters do not face the same standby energy losses as typical tank water heaters since there is no tank of heated water that needs to be maintained at a constant temperature all of the time. How much less do you want? The

Drawbacks to tankless water heaters

The most obvious disadvantage of a tankless water heater is the greater expense of the device itself as well as the labor to install it. Tankless water heaters are more expensive than standard tank water heaters; usually, the unit alone costs around twice as much as the tank water heater, depending on the flow rate required. As a result of the greater BTU rating, they are also more difficult to install due to the particular venting requirements and the fact that they require bigger gas lines than other models.

See also:  What Size Wire For 220V Hot Water Heater

There is a limit to how much water can be given at once, despite the fact that tankless water heaters can offer a limitless amount of hot water on demand.

Tankless water heaters, on the other hand, do not require any maintenance.


When it comes time for me to replace my own water heater, I’m thinking I’ll continue with my current conventional tank. For me, the greater expense as well as the increased likelihood of complications just exceed the additional benefits. In the event that I ever make the decision to install a tankless water heater, I will almost certainly spend a significant amount of time looking over the specifications of the individual type that I pick. Aside from ensuring that the unit is suitably sized, I’ll want to know what the manufacturer’s minimum flow rate is, what sort of water quality the company requires, and what precisely is covered by the manufacturer’s guarantee.

Inspections of one’s own home Subscribe to Reuben’s Home Inspection Blog by entering your your address below.

Installing a Tankless Water Heater

“On-demand” is in high demand these days, whether it’s for movies or information, or for food or amusement. It has even made its way into the field of plumbing, where tankless water heaters have grown increasingly popular since they can provide hot water whenever it is required. Learn about the advantages and disadvantages of tankless water heaters, as well as the installation concerns that come with these contemporary money-savers, before making your decision.

What Are The Pros and Cons?

Tankless water heaters, as opposed to standard water heaters, which heat water in a storage tank, give hot water “on demand,” or just when it is required. The fact that they heat water directly rather than through a tank means that they do not suffer from the same standby energy losses that are associated with storage water heaters. The hot water tap is triggered by turning on the cold water supply, which goes through a pipe into the tankless unit, where it is heated by either a gas or electric element.

Tankless water heaters, while initially more expensive than regular systems, may save a significant amount of money over the long run. Tankless units may save an average family up to $100 or more per year due to the fact that they consume up to 30 to 50% less energy than conventional units.


While it is feasible to install a tankless water heater on your own, it is not a project that should be attempted by unskilled do-it-yourselfers. Tankless water heaters are available in a variety of sizes and designs, including propane, natural gas, and electric versions, as well as single-room and whole-house variants. They are also available in a variety of fuel types. Due to the fact that a typical tankless heater consumes more gas than the largest home furnaces, you will need to consult with your local gas provider to ensure that your gas main is properly sized.

Aside from that, you’ll also have to pay for someone to properly dispose of the old tank.

How to Install a Tankless Water Heater

Instructions from a professional on how to remove an old water heater tank, prepare the area for installation of a tankless water heater, and finally install the tankless water heater Because it does not store a huge amount of heated water, a tankless water heater, also known as an on-demand water heater, saves money over a traditional water heater. Essentially, it serves to give hot water on demand, so you won’t have to worry about the shower suddenly being chilly. The process of installing a gas tankless water heater consists of mounting the unit, connecting the gas and water lines, and installing a flue.

As a result, it is possible that it will not work.

Tankless Water Heater Preparation

Remember to complete all essential preparations before disconnecting and removing your present water heater; you don’t want to be without hot water for a week or two while you wait for any plumbing, electrical, or vent work to be completed. If you are installing a new gas unit, you should determine whether you need to upgrade your gas meter. Because the unit consumes a considerable amount of BTUs, it is possible that your meter does not have the capacity to feed it in addition to the other gas-using appliances in your home.

Have the gas provider inspect the manifold pressure to ensure that it is providing the proper amount of pressure for your system.

Removing the Old Water Heater

In the majority of circumstances, a new tankless water heater will be installed in lieu of an existing storage water heater. In Ron Hazelton’s video above, he refers to our website for the directions, which are as follows: How to Flush or Drain a Water Heater (with Pictures). In order to remove the old water heater, turn off the valves on the two water lines (one for the input and one for the output) that lead into the existing water heater and disconnect them. To remove and detach the water heater’s lines from the water heater, use channel-type pliers or a pipe wrench.

Drain the tank by opening the drain valve located at the bottom.

Fill the tank with water by connecting a hose to the water heater’s drain valve. Don Vandervort writes for HomeTips. On a gas-powered unit, turn off the gas line valve and remove the gas line from the device. Disconnecting and removing a portion or sections

Installing a Tankless Water Heater

Tankless units can be fitted flush against the wall (against the drywall or plaster), or they can be inserted into the wall between the studs. Using a stud finder, identify the studs in the wall where you want to install the unit, and then cut a hole between each of them. Attach the item to the wall in accordance with the manufacturer’s recommendations. Water supply pipes should be routed to the water heater. Make certain that the pipe from the water utility is linked to the inlet and that the pipe flowing to the home is connected to the outlet before starting the project.

You might also want to consider installing a pressure-relief valve.

The water valves should be opened, but not those for the power or gas.

DIY Tankless Water Heater Installation Is Dangerous

However, just because there are safety procedures in place to prevent hot water tanks from exploding does not imply that they are impenetrable to failure. When unlicensed individuals install hot water tanks, the possibility of something like this occurring increases, and the likelihood that they will not have the necessary insurance to pay the damage if it does occur increases. Water heaters, in particular, those run on gas are extremely combustible. An explosion or a fire might occur if one of the installation’s components is mishandled.

Carbon Monoxide Leaks

They are undetectable by the human senses, which is why they are referred to as a silent killer. A competent plumber can help you avoid carbon monoxide poisoning by ensuring that your system is properly vented before the problem occurs. Nonetheless, a CO detector should always be installed. This procedure is crucial for in-home safety, but it is frequently performed incorrectly by inexperienced repairmen. Whatever number of ancient systems your uncle installed years ago, please do not make the fatal error of attempting to install your own water tank on your own dime.

In many cases, amateur installation is not covered by your guarantee.

The majority of internet sales and purchases are canceled right away.

A defective installation, on the other hand, might cause damage.

DIY Can Hurt Your Property Value

Sure, you might be able to do a plumbing task on your own and save some money, but is your handy work up to code? Did you get a permit to do this? When it comes time to sell your property, such blunders might end up costing you a lot of money in the long run.

Read This Before You Buy a Tankless Water Heater

Consider the following: The method used by the majority of houses in this nation to heat water is ridiculously inefficient. Every year, we fill up large storage tanks of 40- to 50-gallon capacity with water and then continuously pump energy into them to ensure that we have hot water available anytime we want it. But, unfortunately, this is not always the case. The wait for the tank to reheat might be lengthy if a teenager is taking a long shower or the spouse is enjoying a long soak in the tub.

Then there are the niggling concerns such as: Is it clogged with silt that consumes energy? Is there a chance of a leak? Both of these worries are fair given the fact that tanks often fail between 8 and 12 years.

Tankless Water Heater Installation: Is It Worth It?

Investing in a tankless water heater has a number of benefits, as detailed above. It creates hot water just when you use it and for as long as you require it, resulting in a reduction of 27 to 50% in fuel expenses when compared to tank-type heaters. (A typical gas-fired tank wastes 40 to 50% of the fuel it burns, according to the manufacturer.) As a result, there is virtually little danger of a catastrophic leak occurring because there is no tank to collapse. Furthermore, since their introduction in the United States in the 1990s, tankless heaters have become increasingly sophisticated, with features such as built-in recirculating pumps (which provide “instant” hot water) and wireless connectivity, which alerts you via smartphone when a unit requires servicing.

In it, we’ll explain how a tankless water heater works, as well as tell you how to use one.

How Does a Tankless Water Heater Work?

Doug Adams created the illustration.

  1. It all starts with the first turn of the hot-water faucet (1). A flow sensor (2) detects the presence of water entering the heater and sends a signal to the control panel, causing the heater to begin generating hot water. During operation of a natural-gas-fueled unit, thecontrol panel (3) activates thefan (4), which pulls in outside air, opens the gas valve (5), which allows the gas to flow into the unit, and ignites the burner (6). In order to transmit heat from the flames to water passing through the exchanger’s tubing, a heat exchanger (number 7) is used. The mixing valve (8) regulates the temperature of the superheated water that exits the exchanger. Whenever the temperature sensor (9) detects water temperatures that are too high or too low for the intended setting, the panel will modify the gas valve, the mixing valve, and the flow-regulating water valve (10) in accordance with the results. an 11-inch sealed vent(or pair of vents) through a roof or other structure

Several people were thanked for their contributions: Phillip Maxwell, Residential Product Manager, Rheem; Eric Manzano, Product Training Supervisor, Noritz; Joe Holliday, Senior Vice President, Product and Business Development, Rinnai; and Fred Molina, Water Heater Products Manager, Bosch Thermotechnology

What to Know About Tankless Water Heaters

Thanks to Noritz for the use of his photo.

How Much Does a Tankless Water Heater Cost?

Prices range from approximately $170 for modest gas-fired units to more than $2,000 for high-output heaters that can serve two showers at the same time; $1,000 is a reasonable starting point for most buyers. Electric heaters without a tank range in price from $90 to $900. The expenses of a first-time installation are higher than the price of a simple tank replacement. Electric tankless water heater installation (see item below headed “Installing an Electric Tankless Water Heater”).

See also:  How To Reset Ecosmart Tankless Water Heater

How to Install a Tankless Water Heater

This is a work that should be left to the professionals, since it entails creating leak-free water, vent, and gas connections in the case of gas or propane units, or upgrading the wiring and circuit-breaker panel in the case of electric units, and it is best left to the professionals.

Tankless Water Heater Maintenance

Sign up to have a professional do an annual service that includes cleaning or replacing water and air filters, as well as inspecting the burner’s operation. The use of a vinegar flush every 500 hours in places with hard water prevents mineral accumulation, known as scale, from blocking the heat exchanger. That 20-minute task may be completed by a professional or by a homeowner.

How Long Do Tankless Water Heaters Last?

It is expected that gas-burning tankless water heaters would last 20 years or longer, which is two to three times longer than tank-type heaters. Tankless electric units have shorter life lifetimes, ranging from 7 to 10 years, compared to conventional units.

Where Can I Buy One?

They may be found at plumbing supply stores, big-box stores, and internet sellers, among other places. Alternatively, you may order one via your plumber.

Pros and Cons of Tankless Water Heaters

Thanks to Noritz for the use of his photo.

PRO: They’re Compact

As a result of new federal requirements requiring stronger insulation to decrease standby heat loss, the size of newer tank-type water heaters has increased.

Consequently, they may not be able to fit into locations where an older heater with the same capacity might. Tankless gas heaters are approximately the size of a suitcase and are mounted on the wall.

PRO: They’re Safer

A tank-type heater, on the other hand, may leak and spill gallons of water if it springs a leak, but it will not house Legionella germs or topple over in an earthquake. The air supply and exhaust vents are also closed to prevent backdrafting, which would otherwise allow carbon monoxide to enter the house.

PRO: They’re Easy to Winterize

Owners of vacation homes are well aware of how long it takes to drain a water-heating tank prior to closing up a house for the season. An electric compressor may drain a tankless heater in a matter of seconds, after which it can simply be unplugged.

CON: They’re Sensitive to Slow Flow

These devices automatically shut off if there is too much scale accumulation in the pipes, or if the aerators in the faucets and showerheads get blocked, or if a turned-down faucet limits water flow to around 0.3 gpm.

CON: The Payback Takes Awhile

An annual savings of only around $100 for a household using a $1,000 tankless gas heater vs a $400 tank-type heater is possible, depending on how efficient the heater is and how much hot water is utilized. The savings, however, begin to accrue after six years, when many tanks are reaching the end of their useful lives due to the extended lifespan of tankless gas systems.

New Tankless Water Heater Technology

Thanks to Noritz for the use of his photo. The advancement of tankless technology is ongoing. Here are a few of the most recent enhancements:

Higher Efficiency

Condensing gas heaters can extract up to 96 percent of the heat from a fuel, which is a 17 percent improvement over first-generation tankless devices. This is possible because of a second heat exchanger, which collects a large portion of the exhaust heat before it exits the vent. In addition to being around 25% more expensive than noncondensing heaters, condensing heaters produce acidic condensate that must be neutralized. If a heater doesn’t come with a built-in neutralizing cartridge, the installation will have to install one after the fact.

Instant Hot Water

Despite the fact that tankless water heaters heat water in around 15 seconds, you must still wait for the hot water to reach your shower head or faucet, just as you would with a tank-type heater. The recirculation pump should be used when the distance between the heater and the fixture is greater than 50 feet. This will conserve water and minimize the amount of time spent waiting. It is this pump that pushes the cold water in the pipes back through the heater. The pump can be activated by a timer, a push button, a motion sensor, a smart speaker, or a smartphone (see illustration above).

Wi-Fi Compatible

Tankless systems with digital connectivity let you to control the temperature as well as monitor gas and hot-water use from your mobile device. Furthermore, the device is capable of identifying the cause of a problem.

Please communicate this information to your plumber so that he or she may arrive on the job site knowing exactly what has to be done. This function also eliminates the need for any guessing when it comes to determining when it is time to descale.

Tankless Water Heater Rebates: A Great Way to Save

Carl Tremblay captured this image.

What Size Tankless Water Heater Do I Need?

Here’s how the specialists ensure that your water heater produces adequate hot water: 1. A large burst of BTUs is required for a tankless heater to convert cold water into hot water in a matter of seconds. However, if a heater’s Btu output is insufficient to meet demand, it will reduce the flow rate or, in the worst scenario, offer tepid water. A plumber considers three aspects when determining whether or not a heater will be able to satisfy the demands of a household:

  • The temperature of the water that enters the heater
  • The maximum demand for hot water expressed in gallons per minute (gpm)
  • The efficiency of the heater, as shown by its Uniform Energy Factor, which may be found in the product specifications
  1. The first step is as follows: A professional determines how many Btus per gallon of water heater is required to increase the incoming water temperature to 120 degrees (see the map on the next slide)
  2. Flow rates for all of the appliances and fixtures that may be consuming hot water at the same time are added together to form peak demand, which is calculated as follows: (These rates are detailed in the next slide.) As a result of not bathing or washing in 120-degree water, we save around 20% on our overall use. Water-saving fixtures and appliances, as well as delaying laundry while the shower is in use, can help you minimize peak consumption. In the calculation, the total Btu production is computed by inserting the Btus-per-gallon and peak-demand amounts in at different points along the way. If the outcome is in between two models, use the more conservative model.

Btus Output Estimate

Not interested in completing the calculations? Make a rough estimate of how much heater output you’ll want using these statistics.

  • The following figures are for one bathroom for one to two people: 140,000 Btus
  • Two bathrooms for two to three people: 190,000 Btus
  • Three bathrooms for three to five people: 380,000 Btus

Btus Per Gallon by Region

  • Kitchen or bath faucets should flow at 1.5–2.2 gpm
  • Tub filler faucets should flow at 4 gpm
  • Dishwasher: 1–2.5 gpm
  • Washing machine: 1.5–3 gpm
  • Showerhead should flow at 1.25–2.5 gpm

How to Determine gpm?

To get the real gpm of a fixture, time how many seconds it takes to fill a bucket to the 1-quart mark and multiply that time by the number of gpm. gpm is calculated by dividing 15 by the number of seconds in a minute.

Electric Tankless Water Heater Facts

Thanks to Stiebel and Eltron for their assistance. In addition to gas lines and propane tanks, tankless water heaters operated by electricity can provide the benefits of on-demand hot water to homes that do not have them. Compared to gas or propane tankless heaters, these systems, which heat water using thick copper rods, are significantly quieter and roughly a third smaller in size. And because they do not require vents, they can be fitted practically anyplace, even beneath sinks and in small closets, without compromising performance.

In locations with warm groundwater, that amount of hot water may be sufficient to feed a whole house; but, in colder climates, they are better suited to point-of-use service, where the demand for hot water does not become excessive.

Tankless Water Heater Installation

Doug Adams created the illustration. What you and your plumber should look for before the installation day is as follows:

Gas Line

If you want your tankless heater to work effectively, you must connect it to a gas supply line that supplies enough volume at a high enough pressure to run the burner. In many circumstances, this will need increasing the diameter of the supply pipe to 3-4 inches in diameter. Furthermore, if the pressure is insufficient, the gas provider will be required to change the regulator on the meter. For your information, some tankless systems, like as ones manufactured by Rheem, are capable of working with a regular 12-inch gas line as long as it is not more than 24 feet in length.


Tankless gas heaters that do not condense employ stainless-steel vents that can resist high exhaust temperatures. Condensing systems feature a cooler exhaust and use PVC pipes, which are less costly than other types of exhaust. Installing a concentric vent, which has an exhaust pipe inside a larger air-intake pipe, is easier than installing a traditional vent since only one hole in the wall needs to be made.

As a point of reference, vent runs have traditionally been limited to a maximum of 10 feet. However, more powerful fans, such as those found in Rinnai’s Sensei series, now enable vents to be extended up to 150 feet.

Water Hardness

Heat transmission is slowed and water flow is restricted when scale deposits accumulate in a heat exchanger (or on electric heating components) over time. If you currently have whole-house water softening, scale will not be an issue for you. However, if your water is not being softened and its hardness surpasses 120 milligrams per liter, it is worthwhile to invest in a treatment system to remove the hardness. For your information, a specific, point-of-use cartridge, such as the TAC-ler water conditioner (Stiebel Eltron), can be used to change the hardness of water without the use of salt or other chemicals.

Outdoor Tankless Water Heater

Matt Risinger captured this image. If your environment and local rules allow it, think about the advantages of hanging a heater outside in the winter.

  • Saves space: You won’t have to create place for another appliance in your home as a result of this. Installation is straightforward: Because of the built-in exhaust vent, there is no need to drill a large hole (or two) through the side of the building. Service is simple: A plumber may come to your home at any time, whether or not you are there. However, take in mind the following: Regulations governing construction: If you want to install it outside, you may require approval from your local building department. Weather conditions that are cold: Even at temperatures as low as 22 degrees Fahrenheit, internal heaters keep components warm, but exposed water lines must be insulated and covered with heat tape that activates automatically in freezing conditions. Southern states are less concerned about frozen pipes than those located north of the Mason-Dixon Line.

Tankless Water Heater Venting

Carl Tremblay captured this image. Are you in need of assistance with repairs around your home? A house warranty may be of assistance. The This Old House Reviews team has put up some in-depth guidelines that you can read here:

  • Home warranty providers that are the best
  • Reviews of American Home Shield, AFC Home Club, Select Home Warranty, and Choice Home Warranty are all available online.

Leave a Reply

Your email address will not be published.