What You Need to Know About Venting a Hot Water Heater
A venting system is required for all water heaters that operate on natural gas or liquid propane (LP) gas. When a gas is burned, the process is referred to as combustion, and it results in the production of heat, exhaust gases (including very toxic carbon monoxide), and moisture. Due to the fact that it eliminates these waste products from the residence, the water heater’s ventilation system is an essential safety component. In the majority of situations, the kind of ventilation system used is dictated by the type of water heater chosen.
This page is not meant to be a set of instructions, but rather to serve as a broad overview of how hot water heater venting works. Don’t try to troubleshoot or remedy problems with your hot water heater’s venting on your own, since poor venting can cause serious health concerns in the long run. If you suspect that your hot water heater is experiencing ventilation problems, call a professional right once.
Water Heater Venting Basics
In order to expel exhaust gases from the water heater to the outside, all water heater venting systems make use of a vent duct or pipe, which is also known as a chimney or flue. Depending on the kind of ventilation system, the duct may be made of metal or plastic. In some cases, water heater ducts can be connected directly to the outside, while in others, they can be connected to a larger vent duct that also feeds a gas or propane furnace or boiler in the home. Acommonventconfiguration is the term used to describe this.
While properly designed conventional venting systems are totally effective, if they are not built appropriately, there is the possibility of backdrafting difficulties.
Once a year, have your gas water heater cleaned and serviced to ensure that the venting system is always in perfect operating order. Gas and propane water heaters, in addition to requiring ventilation, require an air source for combustion. There are two ways in which this might happen: either through the natural ventilation in the house or by a vent pipe that draws air in from the outside.
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Proper Venting Prevents Backdrafting
One of the most prevalent issues that arises when it comes to water heater venting is a phenomenon known as backdrafting. Backdrafting occurs when exhaust gases from a water heater fail to depart through a vent and instead wind up inside the household. Backdrafting may be caused by a variety of factors, the most prevalent of which include improper vent design or installation, as well as an imbalance in the amount of air in the residence. Water heater exhaust gas is commonly drawn downward and into the home by the installation of ventilation fans, such as bathroom or kitchen vent fans, which suck air out of the house and produce a suction effect, drawing exhaust gas into the home from the water heater vent.
Some water heater venting systems, such as those that use fan-assisted ventilation or direct venting technologies, eliminate the potential of backdrafting.
Standard water heaters, which are the most prevalent variety, frequently employ a technique known as atmospheric venting. The vent consists of a vertical or upward-sloping vent duct that connects to a common vent, which is normally located in the ceiling. Natural convection is the only mechanism by which the system operates, and it is based on the idea that hot air rises. The hot exhaust from the water heater naturally rises up through the vent and into the air outside, providing a pull that encourages the upward circulation from the water heater to the outside.
If the atmospheric vent systems are appropriately constructed and the home does not suffer from backdraft concerns, they can function effectively (and without the need of energy).
In addition to the vertical or horizontal vent ducts, water heaters with power venting are equipped with an electric blower fan (which is frequently very silent) mounted on top of the water heater. The fact that the vent does not rely on the buoyancy of hot air means that it may be installed horizontally to exhaust outside the home. Due to the cooler air temperature, PVC pipe may be used for the vent instead of metal pipe, which is necessary for atmospheric venting. The blower is simple to construct and cools the air temperature.
Direct-Vent Water Heaters
The air for combustion in a direct-vent system is obtained through a vent pipe that passes through an outer wall or the roof and into the room. Exhaust gases are vented to the outside either a separate vent duct or a distinct chamber of the same pipe, depending on the configuration (this requires a double-wall vent duct). They effectively “breathe” outside air, which means they are not vulnerable to the effects of backdrafting in your home. As a bonus, they limit the possibility of unintentional fires produced by combustible gases in the vicinity of the water heater.
Water Heaters for Mobile Homes
Water heaters in mobile homes are comparable to those found in regular homes, but they must be specifically constructed for this function. Manufacturers will frequently not warranty a water heater that has been put in a mobile home unless the heater has been explicitly certified for that application. A conventional atmospheric water heater connection in a mobile home frequently necessitates the installation of an exterior access panel. The most probable type of water heater to be found inside a mobile home that does not have access to the outdoors is an enclosed combustion unit with direct venting.
Water heaters in mobile homes are comparable to those found in regular homes, but they must be specifically constructed for this function. Unless a water heater has been explicitly certified for use in a mobile home, manufacturers will frequently not provide a warranty on one placed in a mobile home.
When installing a typical atmospheric water heater in a mobile home, an exterior access panel is frequently required. An enclosed combustion unit with direct venting is more likely to be found within a mobile home that does not have access from the outside.
Standard Atmospheric Vent
Standard atmospheric water heaters are the most popular form of gas water heater used in residential settings. In order to escape the residence, atmospheric gas water heaters must exhaust their exhaust through a vertical or upward sloping metal duct vent. This venting can be devoted to the water heater or it can be shared with other atmospheric vent appliances, such as a furnace, depending on the situation. The principle of atmospheric venting is based on the rise of heated air. This means that the venting must be vertical or upward sloping in order for the hot exhaust to ascend through the venting and out of your home.
Any obstructions or misalignments in your home’s ventilation system may result in the discharge of excess heat and gases into the surrounding environment.
A. O. Smith is a fictional character created by American author A. O. Smith. The electric blower fan on the top of a power vent gas water heater necessitates the installation of an electrical outlet adjacent to the water heater since power vent gas water heaters are equipped with an electric blower fan. The blower is responsible for pushing exhaust and extra heat through the exhaust venting system. Power vent water heaters may be installed either vertically or horizontally, with a longer line to accommodate concerns with space and dimensions in your home.
Power vents are a more energy-efficient alternative since they are intended to use the heat generated by the exhaust to heat water, resulting in significant energy savings.
It is recommended that you hire a competent plumbing contractor to do the installation.
Power Direct Vent
In situations when there is insufficient air for combustion in the space in which you are putting a water heater and you want flexibility around the installation, power direct vents are employed. Before embarking on this installation path, consult with a skilled plumbing contractor to ensure that you require power direct venting before proceeding. Power direct venting is similar to direct venting in that it employs a blower to draw in air from outside your home for combustion and deliver it straight to your water heater, similar to the way direct venting works.
A power direct vent water heater, which is similar to the power vent design, may be installed with PVC pipe to save money on installation expenses. It is vital to remember that they must be installed near a water heater where there is an electrical outlet.
Insufficient ventilation in the installation space of your home makes direct vent gas water heaters the most suitable choice of gas water heater. In contrast to an indirect vent water heater, a direct vent water heater takes air for combustion from outside your home rather than from within. All of the exhaust gases and surplus heat generated by your water heater are vented back into the environment. A direct vent water heater makes use of specific coaxial venting, which features separate chambers for intake air and exhaust air in a single manufactured vent component, which allows for more efficient operation.
They draw and push air from the outside to ensure that there is no backdrafting within your home or building.
It is recommended that you hire a competent plumbing contractor to do the installation.
Concentric Vent Termination
In a coaxial “pipe in pipe” venting system, concentration refers to a configuration in which both the intake air and the exhaust gas vent through a single common assembly. It is possible to achieve an aesthetically pleasing installation with only a single wall or roof penetration. Concentric venting may be utilized with a variety of water heaters, including direct vent, power direct vent, and tankless water heaters. Direct vent water heaters are the most common. The material of the concentric venting, on the other hand, may change depending on the type of water heater being used.
On a power direct vent tank or tankless water heater, a concentric vent termination can be utilized to achieve the same benefits of a single wall or roof penetration while maintaining an aesthetically pleasing vent termination.
It is recommended that you hire a competent plumbing contractor to do the installation.
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In a coaxial “pipe in pipe” venting system, concentration refers to a configuration in which both the intake air and the exhaust gas vent through a single common assembly. Single wall or roof penetrations can be used to create an attractive installation. Diverse types of water heaters, including direct vent, power direct vent, and tankless models, can benefit from the usage of concentrated venting, which is also known as concentric venting. But depending on whatever water heater you have, the material used for the concentric venting may vary.
On a power direct vent tank or tankless water heater, a concentric vent termination can be utilized to provide the same benefits of a single wall or roof penetration while maintaining an aesthetically pleasing vent termination design.
In order to ensure a proper installation, we recommend that you speak with a competent plumber.
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Gas Water Heater Venting Options
When it comes to installing an agas-fueled water heater in your house, you’ll want to take your time and plan out the installation well before beginning. For example, what are your gas water heater venting alternatives are a significant issue. We’ll go over each form of venting in detail, as well as the criteria and some of the potential water heater venting issues that you could run into in the future.
Wate Heater Vent Types
Ventilation consists of two distinct components. Your water heater must be able to properly exhaust flue gases while simultaneously drawing in fresh air from the outside. Due to the presence of carbon dioxide in the exhaust, it must be vented outdoors. Listed below are your three alternatives:
If you have an atmospheric venting system installed, your exhaust will naturally vent out of the building. As a result of its buoyancy, the exhaust will escape through a vertical pipe, most typically up a chimney, where it will be expelled permanently from the house. The air utilized for combustion is drawn from the environment within the home (or garage). The most frequent method of venting a gas water heater is via the atmosphere. It is important to note that the major difficulty with atmospheric vent systems is that they are prone to back drafts (more on that later).
If your water heater has a power-vent setup, it indicates that it circulates air using a mechanical fan to do this. One advantage is that you may vent either vertically or horizontally, and you can position the water heater at a considerable distance from the termination point (often as much as 150′) without compromising performance. This sort of installation may be done in residences that do not have a chimney. You must vent your water heater via stainless steel or metal pipe, regardless of whether you have a tank or tankless water heater.
A condensing unit, which will allow you to vent through PVC pipe, is the only method to eliminate this problem entirely.
Direct vent systems are distinguished by the presence of a sealed combustion chamber and a flue pipe. Double-wall pipes allow them to be vented individually or in conjunction. Direct-vent water heaters, as opposed to atmospheric water heaters, provide greater installation freedom since they may vent horizontally. In addition, they are more silent than their power-venting counterparts when in operation. This Wikipedia page on water heaters may be useful if you have more general questions about them.
Gas Hot Water Heater Venting Problems
Back-drafting is an issue that you should avoid at all costs. This is most typically seen with atmospheric arrangements, and it indicates that your exhaust is not exiting the building properly. Back-drafting is typically caused by an insufficiently designed vent system. Keep an eye out for the following signs:
- The top of the water heater has corroded due to corrosion. Plastic has melted towards the top of the structure, near the draft hood
A manual test can also be performed.
By closing all of the doors and windows, turning off the furnace, and leaving the water heater alone, you may isolate the water heater from the rest of the house. If you see warm air near the draft hood, this indicates that your system is back-drafting air.
Water Heater Venting Requirements
The key is to ensure that your ventilation system has the appropriate amount of size, height, and draft. Here is a list of some minimal minimum requirements, but please do not consider this to be a full list. You will be required to examine and adhere to all applicable local and state codes throughout your stay.
- When venting vertically through the roof, you’ll almost always need to utilize a vent connection to keep the air flowing. Please keep in mind that it must have a rise of 1/4″ per 12″ of horizontal run in order to function properly. Because there isn’t much of an incline, maintaining compliance isn’t normally a problem. This means that the total horizontal distance cannot be greater than 75% of the total vertical distance
- A standard B-Vent chimney pipe requires 1″ clearance, although there is zero-clearance pipe available as an alternative. You must have 6″ clearance for a single-wall pipe, and you cannot run it through a ceiling, floor, or wall unless it is made of masonry or concrete (non-combustible materials). When connecting the draft hood, you must allow for at least 12″ of vertical venting before inserting an elbow fitting into the line. If you have a power vent water heater, do not place it near other appliances that use the same flue.
Check Out Other Helpful Guides
Resources that are related to this topic include: How to Light a Gas Water Heater in 7 Easy Steps Installation of a Gas Water Heater How to Replace a Water Heater Thermocouple in 5 Easy Steps On a water heater, how do you clean the thermocouple? How to Turn On a Hot Water Heater (with Pictures)
Replacing Your Water Heater? Don’t Overlook This One Key Factor
Further information may be found at the following links: How to Light a Gas Water Heater in Seven Simple Steps The installation of a gas water heater Steps to Replace a Thermocouple in a Water Heater On a water heater, how do I clean the thermocouple? How to Turn on a Hot Water Heater (with Pictures)
Is Ventilation Necessary for Water Heaters?
Is it necessary to ventilate every water heater? No, but despite the fact that water heater technology has advanced significantly in recent years, combustion water heaters continue to be the most frequent. That is, the ordinary water heater continues to burn fuel, whether it is natural gas, oil, or propane, and the combustion of that fuel produces byproducts such as carbon monoxide. In the absence of adequate ventilation for the poisonous fumes produced by burning, contemporary water heating would be a potentially hazardous prospect.
Types of Water Heater Ventilation
Unless you’re searching for a solar- or electric-powered water heater, or unless you live in a warm region and intend to install your water heater outside, you won’t have to worry about ventilation. Outside ventilation is required for virtually all other installations, but not every ventilation system operates in the same manner, and as a result, installation requirements might differ significantly. Figure 1 shows an example of an outside ventilation system.
- An atmospheric venting system is one in which the exhaust from a water heater naturally rises out of its combustion chamber and goes up via a typical, chimney-style flue that terminates on the roof of the house or building. In contrast to certain other forms of ventilation, the atmospheric version does not need the installation of a motorized fan, but it does necessitate the installation of an exhaust pipe that extends uninterrupted from the water heater to the roof
- Direct venting and power venting systems both provide greater freedom because neither requires a direct route to the roof, allowing for more creative design. A pipe that extends outside via an outside wall is often used to vent both systems. It is important to note that a power vent water heater draws combustion air from the surrounding environment before using a fan to force the exhaust through the vent. It is possible to use a direct vent system that draws fresh air from the outside and vents it through a horizontal pipe. Because of this difference in functioning, a direct vent water heater may be installed virtually anywhere, but a power vented water heater must be installed in a room with sufficient airflow to function properly.
O’Brian of Supply House explains that the decision between powered and non-powered venting frequently comes down to how the house is planned out and whether or not there is enough space for the venting to be installed. Image courtesy of supplyhouse.com
Even if you want to update to a water heater that vents in the same manner as your previous one, O’Brian suggests talking with a professional. When dealing with potentially fatal gases, it may seem like a basic exchange, but as O’Brian points out, “even slight leakage may be disastrous when dealing with potentially lethal gases.” To put it another way, don’t take any chances. Carry out your study, select an energy-efficient unit with a capacity that suits the demands of your family, and then leave the rest to the HVAC installation.
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How To Vent a Gas Water Heater
Water heaters with gas burners, similar to a furnace, may emit dangerous gases including carbon monoxide, which is a byproduct of the fuel used to light the burner and heat the water in the tank, regardless of whether the fuel is natural gas, oil, propane, or another fuel.
In the same way that you need good venting for your furnace, you need adequate venting for your water heater to exhaust the harmful gases to the outside of your home in order to keep you and your family safe.
What you need to know about venting a gas water heater
Typically, the fumes from a typical gas water heater are expelled by a back draft insert and a flue. In order to prevent air from entering the top of the water heater and increase heat distribution in the tank, a back draft insert is installed. The flue is the venting system that allows fumes to escape safely from the house and be expelled into the outside air. An electric water heater that is equipped with atmospheric venting or direct venting will allow the fumes to exhaust naturally by rising straight up through a vertical vent that is routed to the home’s chimney or through an upward sloping vent that may be routed through the chimney or through a wall and out to the home’s outside.
On some gas water heater types, a power vent blower fan will be employed to suck the exhaust gases out of the chimney and into the atmosphere.
Because the power vent makes use of a fan motor to drive the exhaust gases down the flue, the venting may be made longer and more horizontal, allowing you to choose from a wider variety of installation locations for your water heater.
While you should always check your local building rules to ensure that you are installing water heater venting in the appropriate manner, the following are some general suggestions to follow:
- The use of Type B metal flue piping with a diameter of three or four inches will be required if your water heater is designed to be vented into the atmosphere or directly into the atmosphere. A power vent system for water heaters can be vented using Schedule 40 PVC plastic tubing with a minimum diameter of two inches since the blower helps cool the air flowing through, however other experts say metal pipe is the safest option. Between the draft hood outlet and the first elbow or connector, there should be a minimum of 12 inches of vertical venting. Whenever possible, semi-horizontal pipe should have an upward slope of at least one quarter-inch per foot when used for direct venting. In order for the venting to function properly, the semi-horizontal distance should not exceed 75% of the total vertical height of the venting. In order to prevent air leaks, the venting pipe must be properly sealed where it runs through a wall or into the chimney. An UL-listed chimney or vent cap must be utilized to seal off the opening when venting through a chimney or other opening.
Additional gas water heater venting information and safety tips
- It is important to note that a direct venting system will draw combustion air from outside the residence (via the exhaust venting), whereas a power vent system would draw combustion air from the room air that surrounds the water heater. As a result, water heaters equipped with a power vent should not be put in tiny, enclosed locations. If space constraints necessitate the installation of the water heater in a utility closet, ensure that the closet doors are louvered or that enough room is provided at the top and bottom of the doors to allow for increased air movement. A power vent system may necessitate the installation of a slanted exhaust vent in order to adequately drain moisture that has accumulated in the pipe. Because gas water heaters operate on an open flame, keep flammable things such as paint cans away from the device. Because there is always the possibility that exhaust gases from a gas water heater or furnace can escape into your home, one or more carbon monoxide detectors should be put in your home near the bedrooms. It is necessary to check the detector batteries on a regular basis.
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Repair Clinic sells the appropriate replacement parts for your water heater model, including those produced by Rheem, A.O. Smith, Bradford White, Richmond, and Whirlpool. From powervent fan motors and pressure switches to burner assemblies and anode rods, Repair Clinic has the components you need. Enter the whole model number of your water heater into the search bar on the Repair Clinic website to get a complete list of components that are compatible with your equipment. Repair Clinic’s DIY content collection also has videos and articles on a variety of topics, including how to troubleshoot common water heater problems, how to test specific components, and how to install replacement parts.
While not all State water heaters require ventilation in your house, gas water heaters do require venting if they are installed with the proper materials and in the proper location. When you have determined the proper venting for your application, you will be able to assist in ensuring that your water heater operates safely and effectively. Check with a skilled plumbing expert to be sure you have the proper venting option for your water heater installed.
Standard Atmospheric Vent
The typical atmospheric vent type of gas water heater is the most prevalent form of domestic gas water heater. Atmospheric venting is commonly used to vent exhaust out of a residence and involves the use of a vertical or upward sloping metal duct. Other atmospheric vent appliances, such as a furnace, may be connected to the same vent system or they may have their own specialized vent systems installed separately.
The venting is positioned vertically since hot air rises, which aids in the safe ascent and evacuation of the hot exhaust from the residence.
Statepower vent gas water heaters are equipped with an electric blower fan that is mounted on the unit’s top. This necessitates the installation of an electrical outlet next to the water heater. Blowers force exhaust heat via venting that may be mounted either vertically or horizontally depending on the length of the exhaust line. This allows for greater freedom in determining where the water heater should be installed in the home. Power vents utilise more of the exhaust heat to heat water, making them a more energy-efficient alternative for those looking to save money on their utility bills.
As compared to traditional atmospheric vent metal piping, this is a more cost-effective alternative that is also easier to build.
Power Direct Vent
An energy-efficient direct vent may be necessary when installing a water heater in an area where there is inadequate air for combustion. Power direct venting is similar to direct venting in that it employs a blower to draw in air from outside the residence and deliver it to the water heater, where it may be used for combustion. The exhaust gases are also vented outside the house through a second vent pipe, which is operated by the blower. Power direct vent water heaters, like power vent water heaters, may be installed with PVC pipe, which reduces the overall cost of the installation.
Obtain the services of a competent plumbing contractor to determine whether your house and water heater require power direct venting.
An energy-efficient direct vent may be necessary when installing a water heater in an area with inadequate oxygen for combustion. Using a blower, power direct venting is similar to direct venting in that it pulls in air from outside the residence and directs it to the water heater, where it may be burned. A second vent pipe allows the exhaust gases to be expelled outside the house by the blower. Power direct vent water heaters, like power vents, may be installed using PVC pipe, which reduces the cost of the installation.
Obtain the services of a qualified plumbing contractor to determine whether your house and water heater require power direct venting.
Concentric Vent Termination
Using a concentric venting system with a variety of water heaters, including direct and power direct vent, as well as tankless water heaters, may be the most cost-effective alternative. The material of a concentric vent varies based on the type of water heater you have; nonetheless, this attractive installation choice pertains to any coaxial “pipe in pipe” design. Simply said, this means that the intake air and exhaust gas pass through distinct chambers of the same assembly, rather than through the same chamber.
Concentric vent terminations provide the aesthetic benefits of a single wall or roof penetration while also being compatible with power direct vent or tankless water heaters.
The intake and exhaust pipes for these systems are distinct, and concentric piping is only utilized for the wall penetration and termination.
Separate intake and exhaust pipes are run between the water heater and inner wall. We propose that you seek the services of a competent plumbing contractor for the installation of concentric venting.
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House Water Heater Vent Pipe Tips & How To Do It Right
More information about the water heater vent pipe may be found in my article that follows the video. More vital information may be found by following the links provided below.
- Below the video, you can read more about the water heater vent pipe in my post. The links below will take you to further crucial information.
House Water Heater Venting Video:
More information regarding the water heater vent pipe may be found in my article that follows the video. Follow the links to the bottom of the page for additional crucial information.
There are two common natural draft gas water heater vent pipe systems:
- Natural draft gas water heater – see the next section for further information. induced draft / water heater PVC pipe venting / power venting are all examples of ventilation.
Using a natural draft gas water heater vent pipe system is still the most common method of venting, and it is permissible to do so as long as the property has appropriate structural characteristics and a chimney designed specifically for use with gas-burning equipment. Most connections for natural draft gas water heater vent pipes would resemble the one shown in the figure (one of the issues with these connections is the lack of screws at the draft hood). However, there are certain exceptions to this rule.
some excellent, some awful, of course.
Water heater vent pipe draft hood
A draft hood should be put on top of a natural draft gas water heater, in the middle area of the water heater, directly above where the water heater vent is located. It is supported by three to four short legs, which are either screwed to the water heater top plate, or (depending on the design) have the ends of the legs fashioned like pins or hooks, which are fitted into the holes in the water heater top cover. To ensure effective operation of the gas water heater’s vent pipe system, the Draft Hood must be correctly centered above the vent hole and its legs must be straight; any misplaced or deformed draft hoods should be repaired or replaced as needed.
My guess is that you are aware of how hazardous Carbon Monoxide may be.
- Adding more air to a gas water heater draft hood allows the combustion process gases to be correctly drawn out of the burner chamber (located at the water heater’s base), into the water heater vent pipe and the chimney. Down-draft-preventing gas water heater draft hoods function as a device that stops air from extinguishing the gas burner in the event of down-draft (a circumstance in which the vent pipe / chimney is forced back into it by the wind).
Gas water heater draft hoods are available in a variety of sizes, and if you are changing your water heater, be sure that the draft hood and the water heater vent pipe are the same size as each other. Using an adapter / increaser, you can connect two different diameters of vent pipe together if the draft hood that comes with your water heater has a top opening diameter built for 3′′ vent pipe and you have 4′′ vent pipe installed. It is not necessary to downsize a gas water heater draft hood if it is bigger and intended to accommodate a 4′′ pipe.
Replace the smaller-sized vent pipe with a larger-sized vent pipe that meets the requirements: -most 30 gallons, 40 gallons, and 50 gallons gas water heaters utilize a 3′′ diameter vent pipe; some 50 gallons may require a 4′′ diameter vent pipe; and 75 gallons and more will require a 4′′ diameter vent pipe.
Again, always follow the advice of the appliance manufacturer and adhere to local code standards – and never downsize your water heater vent pipe!
Natural draft gas water heater vent pipe material
You should stick to galvanized steel pipe for natural drafts and avoid experimenting with other materials such as aluminum pipes, food cans with both ends cut off, stainless steel sections, blue stove pipes, high temperature plastic tubing, flexible pipes, and so forth. Reduce the length and straightness of the vent pipe portion between the water heater and the chimney to the greatest extent feasible. Single wall vent pipes are often measured by their horizontal length, which is equal to or shorter than 75% of their total developed height, according to standard practice.
Draft hood and gas water heater vent pipe connections
When connecting the draft hood and the vent pipe, sheet metal screws should be used to hold the connection together – three screws per connection on a single wall pipe is advised. Use of standard duct tape to fasten or seal connections is not recommended. Some building inspectors would not even allow aluminum tape to be used on joints in certain situations. For the simple reason that it conceals flaws such as rust or holes growing on the surface. If you are using a B-vent, which is a double-walled vent pipe, you should only use screws on the first connection – either to the draft hood or to the single-walled water heater vent pipe – since the second connection is not required.
Natural draft gas water heater vent pipe pitch
Sheet metal screws should be used to fasten the connection between the draft hood and the vent pipe – three screws per connection on a single wall pipe is suggested. When securing or sealing connections, do not use conventional duct tape. Aluminized tape is not permitted on joints by some building inspectors. Why? Simply because rust or holes growing on the surface are concealed by this material. If you are using a B-vent, which is a double-walled vent pipe, you should only use screws on the first connection – either to the draft hood or to the single-walled water heater vent pipe – since the second connection will be weakened by the screws.
Natural draft gas water heater vent pipes corrosion
The condition of WH vent pipes should be checked on a regular basis for corrosion and degradation. In most cases, problems with adequate drafting, chimney conditions, and combustion air concerns are the root causes of galvanized pipe corrosion. Small holes begin to emerge on their surface; the most prevalent locations are around the bottom section of the product and on connecting points. At some point, the wall of a corroded gas water heater vent pipe becomes exceedingly fragile, and it may even collapse when subjected to even modest pressure.
Corroded gas water heater vent pipes should be replaced as soon as feasible in order to avoid the potential of exhaust fumes/Carbon Monoxide contaminating the environment.
Water heater vent pipe clearances and restrictions
Corrosion and degeneration of WH vent pipes should be checked on a regular basis. Corruption of galvanized pipes is typically caused by challenges with adequate drafting, chimney conditions, and combustion air concerns. Small holes begin to emerge on their surface; the most usual locations are around the bottom half of the product and on the connecting points. Corroded gas water heater vent pipe walls become quite soft after a while, and they may even collapse when subjected to even the slightest amount of force.
- It is not possible to use single wall natural draft gas water heater vent pipe in unheated areas such as the attic or garage (even if only partially penetrating that space), because such vent pipe installation will cause excessive condensation on the vent pipe walls and compromise proper drafting – double wall pipe or B-vent type is required
- Inaccessible places such as walls, ceilings, and other inaccessible regions cannot be served by single wall natural draft gas water heater vent pipe
- Instead, double wall type vent pipe / B-vent must be constructed
Considering transferring your natural draft gas water heater to the garage or basement storage area? Check out this critical piece of information: the specifications for a garage water heater. More information about natural draft water heater venting may be found in the gaswater heater vent pipe clearances page. a group of in-house writers under the direction of a former Illinois home inspector CTH Expert material is seen by over 2,000 people every day and is dedicated to answering the numerous questions that house owners and home purchasers have about their homes.
How to Install a Power-Vented Water Heater
Mr. Fix-It-Up-For-The-Family Reduce excessive energy bills by replacing an electric water heater with a natural gas or propane heater. Then, to save money on installation expenses, choose a power-vented type that can be readily vented out a sidewall or a roof vent.
Installing a power vented water heater
Mr. Fix-It-Up-For-Us. Reduce excessive energy bills by replacing an electric water heater with a natural gas or propane water heater, and then lower installation costs by installing a power-vented model that can be readily vented through a sidewall, as shown in the illustration.
Natural-draft water heater
A metal duct directs the hot exhaust gases from a natural-draft water heater to the outside. An open draft diverter directs the gases to the outside. The operation of natural gas or propane hot water heaters is normally less expensive than that of electric water heaters, but constructing a conventional vent in a house that does not have an existing chimney is more expensive. You’ll have an easier time running the vent if you choose to install a “power-vented” natural gas (or propane) water heater.
- The majority of them feature a “natural-draft” style of vent, in which the hot waste gases rise via an open draft diverter and into metal pipes that finally flow outside.
- It’s best if you leave it to the professionals.
- Due to the fact that this approach does not rely on the inherent buoyancy of hot air, the vent pipes do not need to be installed higher up.
- Furthermore, because the fan dilutes the exhaust with colder air, you may run the vents using PVC tubing that is simple to build.
Power venting is a particularly suitable option for more energy-efficient, closely constructed homes, where it is difficult to create a decent natural airflow due to the tight construction. However, you should be aware of the following disadvantages:
- The fan may be making a noise that you can hear. As a general rule, the water heater should be located in a room separate from the main living space in order to avoid being a nuisance. You must have a normal electrical socket near the unit to supply power for the fan
- You must ensure that you have an appropriate supply of “make-up” air to replace the air that is being blown out
- And you must ensure that the machine is properly ventilated. The third point to mention is that power-vented water heaters are at least 50% more expensive than natural-draft water heaters. Power-vented water heaters are available practically anywhere water heaters are marketed
- They are manufactured by almost every major water heater manufacturer.
If you opt to install one yourself, make sure to thoroughly read the installation instructions and to adhere to all ventilation requirements. Additionally, contact your local building department to see whether you require a plumbing permit to do the repair.
- Power-vented water heaters are more expensive than natural-draft water heaters, but they are less expensive to install if you don’t already have a chimney. You should be knowledgeable with plumbing, gas piping, and electrical wiring, and you may be required to have the project examined.
Required Tools for this Project
Make a list of all of the equipment you’ll need for this DIY project before you begin; you’ll save both time and frustration this way. If you’re installing a power-vented water heater, you’ll need wiring and plumbing tools, as well as a hammer drill and masonry tools if you’re running the vent through a masonry wall.
Required Materials for this Project
Preparing all of your stuff ahead of time can save you time and money on last-minute buying visits. Here’s a list of things to do.
Inspecting a water heater vent connector
Knowing what to look for while inspecting a natural draft water heater vent makes the process go swiftly and efficiently. What you should check for when purchasing a water heater vent connection is what I’ll demonstrate today. In recent blogs, I talked about evaluating water heaters and testing for correct draft at water heaters, but I couldn’t fit the section about inspecting water heater vents into those posts since the information was too lengthy. I think it deserves to be discussed as a stand-alone issue, so let’s get started., resolvedBy: manual ” data-block-type=”32″>” data provider name=””>
To begin, I must describe exactly what this blog article is about: checking a natural draftwater heater ventconnector (also known as a vent connection). If you’re examining the vent on a powervent water heater, ensure sure someone followed the manufacturer’s installation recommendations by reading the friendly handbook (read the friendly manual first). Every piece of information you want will be included in the installation manual, including what materials are permitted, what size vent is required, how long of a run is allowable, and where it is expected to end.
When it comes to natural draft water heaters, it’s critical to understand the difference between the vent and the vent connector.
Most of the time, it will consist of a straight vertical stretch of UL-listed double-wall class-B vent.
It is typically more horizontal in nature than it is vertical in nature.
LENGTH AND WIDTH
A 3′′ vent connector used to be typical practice for water heaters, but currently only a 4′′ vent connector or bigger is permitted for water heaters under certain conditions. For residential installations, it is quite rare to find anything other than a 4′′ vent connection on the wall plate. As for the length of the vent connection, this is a difficult one to determine. In general, the shorter the sentence, the more effective it is. It is possible for backdrafting to occur when a vent connection is used for a lengthy period of time.
In accordance with national fuel gas rules, the vent connector is permitted to have a horizontal run of 1-1/2′ for every inch of vent connector diameter.
There are certain exceptions to this rule that allow for longer runs, but this is a solid general rule to adhere to.
However, there are situations when it will still operate just fine, which is why it is critical to test for good draft and search for traces of earlier backdrafting before proceeding.
Please refer to my previous blog post on how to test the draft at a water heater for further information on this issue.
Water heater vent connections must be pitched upward at a rate of at least 1/4 inch per foot of length. In an ideal world, much more would be possible. When water heater vents are not correctly pitched, they have a larger chance of backdrafting. The graphic below, courtesy of Dr. Seuss, depicts a water heater vent connection that has been installed in a hilariously inept manner. While the corrugated material seen above is clearly not intended for use as a water heater, there is a very similar variant of it that is permissible for use in this application.
This is a very acceptable product.
Gas vents may get extremely hot, and they must be kept at a safe distance from flammable things in order to avoid damage. Just to be clear, unless anything is specifically designated as noncombustible, everything is combustible. This comprises components such as wood and the paper face of drywall, among other things. For single-wall vent connections, there must be a minimum of 6 inches of distance between them and anything that might catch fire. Installing shields in conformity with Section 308 of the Minnesota Fuel Gas Code can help to lessen the amount of clearance necessary in some situations.
- To be honest, I don’t have any similar photographs of burning caused by a faulty water heater vent connector because I’ve never witnessed it occur.
- Most of the time, it is an installation that has been in this condition for many years, with no evidence of previous difficulties and no indication that there would be problems in the future.
- The second form of vent connector that is commonly used is the double-wall vent connector.
- Almost all B-vents require one inch of clearance from combustibles, however this is not always the case.
- B-vents are shipped with a label showing the minimum clearance that must be maintained.
ORPHANED WATER HEATER
When a water heater shares a vent with a bigger appliance, such as a furnace, you’ll normally have a larger 6′′ or 7′′ vent to accommodate all of the heat generated by the combined appliances. In the winter, when the furnace is capable of heating the vent and keeping it warm for the most of the time, this is satisfactory. If the furnace is replaced with a high-efficiency furnace, the old vent will no longer be used, and the new furnace will vent out out the side of the building through a PVC vent.
A visual representation of this may be seen in the figure below, which was given by the Minnesota Department of Commerce’s Division of Energy Resources.
This can also result in an excessive amount of moisture inside the vent, which can cause the vent to corrode and deteriorate.
In addition, the wording in the image above suggests the installation of a power vent for the existing water heater.
There are two types of devices made by Tjernlundof White Bear Lake, MN: one is a powervent conversion kit for an existing water heater and the other is a chimney stack assist kit for an existing water heater.
A water heater that shares a vent with another appliance must be installed near the bottom of the vent stack since it is the biggest appliance. This is done in order to assist in promoting adequate draft for the smaller appliance, which is often the water heater, to operate well. Also. It is necessary to configure the vent connection such that the water heater’s vent fan does not cause the furnace’s vent fan to backdraft if the water heater shares a vent with a draft-assisted furnace. There must be no space between the two vent connections, otherwise the water heater will backdraft every time the furnace is turned on at the same time as the water heater.
When it comes to correctly venting a hot water heater through a wall, it is important to first understand the many types of venting that are available to you to choose from. You can refer to the following list of popular water heaters, which includes information on the sort of venting they require for installation. This page also includes information on installing water heaters in mobile homes, which requires special care in such sensitive settings. For more details, see the related article.
Atmospheric Water Heater
Water heaters that operate on air pressure are quite prevalent. This water heater may be found in a variety of residences, including mobile homes, where it must be installed outside to function properly. Environmental venting works by using the pressure and temperature differentials that exist between the outside and interior of the home to move exhaust gas upward and across the vertical pipe. When used with this sort of water vent heater, any standard vent will typically function properly; however, it will be more susceptible to being back drafted.
If you notice any of these indicators, you should contact your gas company immediately, and if they are not accessible, you should contact a plumber as soon as possible to avoid any illness or property damage from occurring.
In the event that you decide to install or replace your current water heater with a portable one, make sure you get a portable hot water heater as well.
You need also make certain that there is an external panel that will be able to reach the specific water heater, which should only be the case if you will be using the correct water heater.
Direct Vent Water Boiler
Besides the direct vent water boiler, there are a few more types of water heater venting that you should be familiar with. The air that will be utilized for combustion will be supplied by the water vent, which will be located either on the roof or on the exterior of the wall, depending on the location. This vent also provides for the release of off-gasses to the outer environment. By bringing in fresh air from the outside, you will be able to reduce the likelihood of unintentional fires caused by flame-creating gases that may be present in the vicinity of your hot water heater.
- One advantage of a direct vent model is that it will aid in the elimination of any problems that may have arisen as a result of insufficient interior ventilation.
- Because only one pipe is required to pass through the roof or wall where clean air is transported and off-gasses are vented, only one pipe is necessary to pass through the roof or wall.
- In your mobile home, the direct or indirect combustion should be sealed at all times.
- If you intend to replace your existing water heater with a new one of the same type, you should be sure you replace it with an identical unit.
As a result, combustion water heaters in mobile homes vent over the roof as if they were typical atmospheric gas water heaters. It does, however, obtain its fresh air through a bottom intake air vent that goes below the temporary house and out to the outside of the building.
Ventilated Water Heater
The power ventilated water heater is the final type of hot water heater vent that we will discuss in this article today. These power vent variants are equipped with a blower that is frequently exceptionally silent. It is located at the very top of the water heater and may be used in both horizontal and vertical applications depending on the configuration. It is possible to operate it horizontally since the vent does not require the buoyancy of hot air to function properly. The blower also helps to keep the air cold, which allows the vent to move more smoothly through the PVC pipe.
If you decide to take this blower into consideration, keep in mind that you will require an electrical outlet within 6 feet of the blower.
All you have to know is that venting any water heater is quite crucial and required for a comfortable living environment.