How To Vent Gas Water Heater In Basement

Different Ways on How to Vent Gas Water Heater in the Basement

We have a variety of methods for venting a gas water heater in the basement, which you can read about here. 1279Views As a homeowner, you must find the process of installing a water heater to be quite difficult. Because you are not a professional, you shouldn’t be concerned about it too much. However, it is important to remember that you should never grow overconfident in your abilities. If you come into duties that are foreign to you, you should be prepared to deal with the situation effectively.

It’s simple: you won’t, which is why we created a step-by-step tutorial specifically for you!

Essentials and Steps That You Should Know

During this post, we will instruct you on the following topics:

  • Introduction to Water Heater Vents
  • Different Types of Venting
  • Everything You Need to Know About Vent Pipes
  • Gas Water Heater Venting Installation

The Basics of Water Heater Vents

Introduction to Water Heater Vents; Different Types of Venting; Everything You Need to Know About Vent Pipes; Gas Water Heater Venting Installation

Different Forms of Venting

The following are some of the most prevalent types of venting that you should be familiar with before beginning the installation process:

Direct-Vent Water Heaters

An exterior door or a ceiling with a direct event mechanism provides the combustion air, which is drawn in by a ventilation tube that goes through the door or ceiling. Amorphous gas is vented to the outside by a separate ventilation duct or through a different chamber in the same pipe, depending on the configuration. Direct-vent devices are inherently “responsive” to the indoor environment, and as a result, they are not subjected to the effects of home backdrafting. They also lessen the possibility that combustible gasses in the vicinity of the boiler may cause a random explosion to occur.

Mobile Home Water Heaters

While heating systems for mobile homes are equivalent to those found in standard residences, water heaters for trailer homes are still in the early stages of research and development. Water heaters installed in a mobile home and maybe not specifically permitted by the manufacturer are not covered by the manufacturer’s warranty in the vast majority of cases. In travel trailers, typical atmosphere-conditioned water heaters usually include an external entrance board to allow for easy access. Due to the lack of outside connections to a mobile home, a hot water tank is most often used as a restricted burning device that requires fast venting.

The Power Venting Method

While mobile home heating systems are equivalent to those found in regular residences, trailer home water heaters are still in the early stages of development. Water heaters installed in a mobile home, even if they are specifically allowed by the manufacturer, are not covered by the manufacturer’s warranty. An exterior entry board is common in travel trailers that use standard atmosphere-conditioned water heaters. In the lack of external connections to a mobile house, a hot water tank is most likely a restricted burning device that requires urgent ventilation.

Atmospheric Venting Technique

The most common form of standard water heaters employs air ventilation as its primary mode of operation. An upward or vertical tube serves as the ventilation system’s primary means of delivering frequent ventilation. The gadget operates only on the basis of natural circulation, which is based on the concept of rising heated water. A thermal pipe from the heating system is naturally drawn out by the ventilation system and into the atmosphere, which aids in the promotion of upward airflow by the ventilation system.

With the heating of the vent pipe, the pulling energy becomes more efficient. Atmospheric ventilation systems perform successfully because they are well developed and because there are no underlying issues in the house.

Gas Water HeaterVenting Installation

  1. When it comes to ordinary water heaters, the most common variety is those that utilise air venting. The ventilation system is comprised of a vertical or uphill tube that is often bound to regular ventilation. Because the gadget is based on the idea of rising heated water, it can only work through natural circulation. A thermal pipe from the heating system is naturally drawn out by the ventilation system and into the atmosphere, which aids in the promotion of upward circulation. Heat generated by the vent pipe results in an increase in drawing energy. As a result of their proper construction and the absence of any background difficulties, atmospheric ventilation methods perform admirably.


  1. Check for adequate venting by doing a simple visual inspection to ensure that pipes are not corroded or covered with white condensate. Check to see that there is no water on the tank’s surface and that the burner does not exhibit signs of excessive corrosion. To avoid development from the container, turn off the water heater and wait 1-2 hours for warmth to build up in the room. Keep a candle lit within 1 inch of the vent hood and check to see whether smoke is sucked into the ductwork. Alternatively, if the smoke does not draw, check for roof vent obstructions or consult a plumber.

Preventing Backdrafting

Make a simple check for adequate venting to ensure that the pipes are not corroded or covered with white condensate before proceeding. Check to see that there is no water on the tank’s surface and that the burner does not exhibit signs of excessive corrosion. Stopping and waiting for warmth to build up in the water heater will help to avoid growth in the container. If there is no smoke sucked into the vent hood, keep the light on within 1′′ of it. A plumber should be called if the smoke does not draw due to a vent restriction on the roof.

Tips to Remember

  1. Clearances from the air heater must be maintained to allow for uninterrupted airflow into the facility as well as proper ventilation of a gas water heater, open areas inside and beyond the region. It should be necessary for the water heater manufacturer to provide recommendations and regulations in order for the gas heater to be opened. Cold air is meant to be free of combustible vapors and corrosive components
  2. The ventilation pipe should be at least as large as the holes in the insulation. It is not permitted to provide fresh air in areas where the differential pressure exceeds a certain threshold, such as areas where exhaust ventilators, ovens, dryers, and fireplaces are located. If your tank has been exposed to high amounts of sediment, the disposal valve may get clogged. This piece of paper will assist you in the process of draining the tank. If the exhaust pipe is in good shape, you may use it with your new heater. If it is not, you should replace it. You should also be permitted to utilize the Temperature/Pressure release tube, which should be in perfect working order. It is recommended that you get your heating system checked prior to removing your old device in order to ensure that it is in proper working order. Remove the old heater from the room and dispose of it. The heater must first be drained and pushed out of the way with a side lorry. Check the tag on your old water heater to see whether it’s still functional. It is necessary to specify the weekly energy usage as well as the tank volume. Both are beneficial in terms of being chosen for your new water heater

It was definitely a sweaty experience learning how to properly vent a gas water heater in the basement. However, I hope that the advice I provided has assisted you in becoming the most dependable member of the home when it comes to DIY projects. Still have reservations? Our recommendations are as follows:

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.

Need more help? Talk to a water heater expert

Our partners can assist you in comparing quotations from highly rated specialists in your area. Request a Quote In this table, the offers that appear are from collaborations from which The Spruce earns a commission.

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.

Atmospheric Venting

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).

Power Venting

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.

See also:  How Long Does It Take For Hot Water Heater To Reheat?

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.

Power Vent

Standard atmospheric water heaters are the most popular form of gas water heater installed in a home environment. In order to escape the residence, atmospheric gas water heaters must exhaust their exhaust through a metal duct vent that is vertical or upward sloping. A dedicated water heater venting system or a shared venting system with other atmospheric vent appliances, such as a furnace, can be installed. Using the notion of hot air rising, atmospheric venting is used. A vertical or upward sloping venting system is required to ensure that warm exhaust is drawn upward and out of your property.

Any obstructions or misalignments in your home’s ventilation system may result in the discharge of excess heat and pollutants back into the surrounding environment. In order to ensure a proper installation, we recommend that you speak with a competent plumber.

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.

Direct Vent

In situations when there is insufficient air for combustion in the space in which you are putting a water heater and you need flexibility around the installation, power direct vents are employed. Make sure you require power direct venting before proceeding with this installation by consulting with a skilled plumbing contractor. 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 does.

PVC pipe can be used in a similar manner to the power vent design in order to decrease installation costs on a power direct vent water heater.

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.

Request a quote from a local pro

Water heaters manufactured by A. O. Smith are professionally installed by independent contractors in the local area. GET IN TOUCH WITH A LOCAL INSTALLER

Not sure which water heater is right for you?

Water heaters manufactured by A. O. Smith are professionally installed by independent contractors in the local community. DISCOVER AN INSTALLER IN YOUR AREA OF RESIDENCE

Contractor Resources

  • Detailed Instructions for Setup Instructions for installing a water heater may be found here. See the document
  • Guide to Obtaining Resources Match the flow rate to the requirements of your customers. Cross-reference tool for viewing documents Look for replacement products that are NAECA-compliant. Make use of a tool.

Replacing Your Water Heater? Don’t Overlook This One Key Factor

Image courtesy of When a home’s plumbing system is in good working order, homeowners seldom give the water heater a second consideration. A very different narrative unfolds when this critical appliance fails, interfering with all of the basic daily tasks that depend on having a constant supply of hot water available. When that happens, and you’re forced to take cold showers or wash your dinner dishes by hand, you’re likely to find yourself thinking about your water heater quite a bit.

  • Rushing this choice, on the other hand, would be a mistake.
  • The type of water heater you pick will have a significant impact on how much you’ll end up paying to heat water on a consistent basis in the future.
  • “Taking your time” is a good idea for a variety of reasons.
  • If you don’t, you’ll almost certainly wind up spending more for installation than is actually necessary.
  • In the words of O’Brian, “A replacement that saves you a significant amount on your energy expenses may be well worth the additional installation cost.” When evaluating your water heater alternatives, it’s important to address the issue of ventilation.

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

Get Help

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.

Consult with a professional Identify qualified plumbing professionals in your area and receive free, no-obligation quotes for your plumbing project.+

Backdrafting Water Heaters

Backdrafting is quite widespread in new homes, particularly in western Shawnee and southern JOCO. Backdrafting is more likely to occur in a house that is more tightly built. The primary source of the problem is an unbalanced HVAC system, which causes negative pressure throughout the whole basement of the residence. Take a moment to consider how a gas water heater operates: the only thing stopping the exhaust from entering your home is the air pressure created by the heat rising through the flue of the heater.

  1. This implies that they do not have a fan to drive the exhaust outside of your home when they are in operation.
  2. Nonetheless, modern houses are more energy efficient than ever before, and a variety of environmental or environmental factors might cause your water heater to vent into your home.
  3. In the summer months, it is significantly more probable that a water heater would backdraft than it is in the winter.
  4. There will be dampers installed in several systems, which will redirect more air from the basement to the top area of the house.
  5. This is indicated by the presence of doors that close on their own and the sensation of air rushing down to the basement.
  6. The first step is to locate and inspect the cold air return ductwork to ensure that there are no major leaks or holes in the system before proceeding.
  7. These returns are frequently pulled directly from the blower and pull far more air than they should.
See also:  How To Clean Sediment From Water Heater

There are a few of fake remedies for the problem of backdrafting that you may try.

Additionally, keeping a supply air register open in the basement or mechanical room might assist in keeping the system balanced.

Almost all of JOCO’s venting is not sized or set in line with the sizing criteria of the Fuel Gas Chart.

Exemple 1: An incorrectly sized vent This image depicts one of the most prevalent venting concerns that we see on a daily basis.

Installed water heater was a 40,000 BTU unit with a single wall vent measuring 3 inches in diameter.

As a result, for numerous years, this water heater was backdrafting into this residence.

When the homeowner had a new high-efficiency furnace installed, the problem was not properly addressed.

A 4′′ vent was added in place of the branch that was previously utilized to connect the furnace.

Example3 – A number of water heater issues at the same time Another example of a faulty installation in a newly constructed house.

Backdrafting may be seen at the top of both the left and right water heaters, as shown in the photo below.

Old water heaters had a 3′′ vent that came out of the top of the tank and did not have a connecting riser.

When the vents join, the new system has a connection rise, 4′′ vents coming from the separate tanks, and a 5′′ rise when the vents combine.

The issue is typically worse during the warmer months.

If the basement’s supply of air is restricted, it is critical that the amount of air extracted from the basement be kept to an absolute minimum.

It is also the most difficult. Secondly, in some homes, it is necessary to ensure that combustion air passage louvers are installed into the mechanical room and, in some circumstances, even down to the basement, which is accessible from the first floor.

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.

  • Vent pipe draft hood, water heater vent pipe material, water heater vent pipe connectors, water heater vent pipe pitch, and water heater vent pipe corrosion are all covered. Clearances and limits around water heater vent pipes

House Water Heater Venting Video:

I strongly propose that you read House Brick Chimney Problems if you want to completely comprehend natural gas water heater venting in your home. Achieving the Proper Chimney Flue Sizing for Your Gas Water Heater and Furnace – several of the water heater vent pipe parameters listed below are dependent on a properly working and fitted chimney! Check out my latest post, which explains tankgas water heater maintenance and water heater check in detail. It is quite crucial!

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.

  1. 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

In order to provide enough airflow, the gas water heater vent pipe connection must be continually routed upwards toward the chimney entry, rising not less than 1/4 inch each linear foot. Some installations may be difficult, if not impossible, to complete due to the height of the water heater and the level of the chimney flue connection; in these instances, an induced draft motor-equipped water heater may be considered.

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.

Water heater vent pipe clearances and restrictions

Installation of a single wall gas water heater vent pipe / connection cannot be done closer than 6 inches from any flammable materials (e.g., floor / wall frame, paper, and so forth). A pyrophoric environment and a fire danger might be created by such an installation. When a material burns spontaneously at a substantially lower temperature when subjected to heat on a continuous basis, this is referred to as the pyrophoric state.

So, for example, if something would usually ignite at 500 degrees Fahrenheit, by applying steady heat to it, the ignition temperature might be reduced to, say, 250 degrees Fahrenheit — this is just an example.

  • 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.
  • However, you should be aware of the following disadvantages:
  1. 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
  2. You must ensure that you have an appropriate supply of “make-up” air to replace the air that is being blown out
  3. 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
  4. They are manufactured by almost every major water heater manufacturer.
See also:  How To Increase Water Pressure On Well Pump

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.

Are my direct-vent water heater flues installed in a standard manner?

We recently moved into a house that had two water heaters built in the basement, one on each floor. It was pointed out to us during the inspection that the water heaters were reasonably modern, but that the exhausts were “weird.” When we noticed a strong gas smell in the basement yesterday, we immediately contacted the gas company. The representative informed us that the source of the problem was a downward draft of flue gas. A plumber came over and informed us that he had never seen anything like this before.

I’ve included two photos of the exhaust system in action.

The vent is protected with silver HVAC foil that has been glued around it.

If you reseal the duct with foil tape and poke holes in it, will it be helpful in allowing the exhaust to escape?

Q&A: Gas Appliances in Basement

Q.I’m renovating a single-family home with a finished basement in order to make it more energy efficient. It is possible to find the furnace and water heater in the basement. Several propane appliances, such as furnaces and water heaters, have been approved for installation in the basement, according to the local fire marshal. He refers to the International Residential Code (Chapter 24) as well as the National Fire Prevention Association’s LPG code. In contrast, the local building inspector references theUniform Plumbing Code, which he claims prohibits the use of liquid-fueled appliances below grade, even in a basement, according to the inspector.

Who is correct?

The following is a response from Mike Casey, a certified plumbing contractor in California and Connecticut and coauthor of Code Check (Plumbing and HVAC).

When it comes to residential property alterations, the building official often has the last word in most communities.

It is true that Section 1213.6 of the 2000 Uniform Plumbing Code prohibits the installation of water heaters in basements or pits where “heavier than air gas may gather and result in the formation of a potentially combustible combination.” Section 304.6 of the Uniform Mechanical Code (version 2000) specifies roughly the same thing for all liquid-fuel gas appliances.

You might inquire with the building authority about whether or not such an alternate way would be acceptable.

power vent water heater in basement using inside air ?

Okay, first and foremost, hvacvegas You would be mistaken, as I have no intention of doing it myself. It appears that every time someone on this board asks a question or a series of questions, the board police are there to remind them that “no diy.” We get it; if you are not comfortable answering the question, don’t answer it. Thank you very much! My current heater is powered by electricity rather than genduct. Once again, this is NOT in a room; rather, it is in an open 25 × 50-foot basement space.

  1. Now, Jim, you always seem to be the voice of reason around here, so thank you for that.
  2. Here’s the deal: I simply want to be sure I’m asking the right questions, or at the very least that I know what questions to ask.
  3. In order to install any unit, you can go to ANY appliance store and purchase any unit, and they will instruct you on how to do it IF that is what you want to do.
  4. If I decide to replace my current electric model with another electric model, I will install it myself, just as I did with the current model.
  5. Once again, thank you!

r/Plumbing – Water heater venting through foundation wall

hvacvegas is the first and most important thing. If you think I’m going to do it myself, you’re mistaken. Every single time someone asks a question or a series of questions, the board police appear to remind them that “no diy” is required. We understand this, and if you are not comfortable answering the question, don’t answer it. Please accept my thanks. My current heater is powered by electricity, not genduct. Once again, this is NOT in a room; rather, it is in an open 25 × 50 foot basement space.

  1. And once again, Jim, you appear to be the calming presence in this room; many thanks for your help.
  2. To summarize, I just want to make certain that I ask the appropriate questions or that I at least have a general idea of the appropriate questions to ask.
  3. In order to install any unit, you may go to ANY appliance store and purchase any device, and they will guide you through the process.
  4. If I decide to replace my current electric model with another electric model, I will replace it myself, just as I did with the current model.
  5. Please accept my gratitude one again.

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
  • Condensation

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)

Leave a Reply

Your email address will not be published.