Learn and explore tips on how properly to vent a gas water heater and safely remove exhaust gases to the outside atmosphere.
A professionally installed venting system is important for all gas heating devices so they can operate safely and adequately remove products of combustion and water vapor out. To answer the question; how to properly vent a gas water heater, use the checklist below, which provides the answers for:
Finding the proper location and installing a gas heater is very important as the proper venting provides better heating performance and safer operation.
If you don't know how to vent a gas water heater properly, consult local or national plumbing codes, and check the manufacturer's instructions.
Also, keep in mind that combustion and ventilation requirements will determine where the unit will be located; if the area is confined, unconfined, or your gas unit is located inside the small rooms and closets. You can also call a professional to do it for you or get a few free estimates from local plumbers by filling out the form.
Confined areas are considered as areas with less than 50 cubic ft. for every 1000 BTU of the total input for gas-fired appliances. Lots of air has to be provided for water heaters located in confined spaces or small enclosures. Two permanent openings are needed for normal venting, one 12" of the top and one 12" of the bottom of that enclosure. The size of the opening is determined by the total BTU input of gas-fired appliances inside that room.
If the air is supplied from the adjacent room, the total volume of these rooms has to provide enough fresh air for combustion and ventilation.
If the air is coming from the outside, it can be transferred directly or using vertical and horizontal ducts, which should be with the same cross-sectional area as the free area of the opening.
For an unconfined space, or open area, indoor air is used for combustion, and the requirement for proper venting is a minimum of 50 cubic feet for every 1000 BTU of the total input of all gas-fired appliances located there.
A water heater vent system and air supply requirements are as described, and it is essential to locate the heating unit as close to the chimney and venting system as possible. The venting system must be able to run from the heater to the exit with minimal length and elbows.
Ensure proper drafting at the draft hood on the top of the tank-type atmospheric water heater. If there is a problem with the correct venting, check the following:
For the proper venting products of combustion the chimney has to be clear and free of any obstructions and, according to the codes. The chimney has to be certified for this purpose.
How to properly vent a gas water heater? For the adequate connection to the chimney, follow the next requirements:
According to the manufacturer's instruction, atmospheric gas water heaters with vertical venting must be installed with the UL-listed type B vent pipe. The vent pipe must be terminated in a vertical position with a listed cap only, and it can be combined with the chimney as long as the proper draft is established.
How to properly vent a gas water heater? The recommendation is to follow codes, standards, manufacturer instructions, and tips provided here.
For example, a 90-degree elbow installed on the top of the draft hood can reduce the efficiency of vents by 50%. This is why it is important to allow a rise of ten vent diameters off of the top of the unit and before the first elbow.
Due to carbon monoxide and fire hazards, check the venting system at least once a year.
This is what you should check during the inspection:
Here is another tip on how to properly vent a gas water heater: conduct a spillage test or draft test.
Let the unit run for up to 15 mins so it can create a steady upward draft of combustion gases.
Put a lit match or piece of paper close to the relief opening of the draft hood. If the steady flame or smoke is drawn into the opening, you see the proper draft. If the flame flutters, it is blown out, or is blown back and away from the unit, combustion products are escaping because something is restricting the venting.
And that is why gas water heaters are equipped with a thermal switch that can shut off the gas supply when the unit is exposed to flammable vapor or due to poor combustion caused by the blocked vent or insufficient combustion air.