Gas-Fired, Residential Storage Type Water Heaters

There are five different types of tank-type gas-fired water heaters.

1. Atmospheric induced draft water heaters
2. Direct vent, induced draft water heaters
3. Atmospheric forced draft water heaters
4. Direct vent, forced draft water heaters
5. Flammable Vapor Ignition Resistant (FVIR) water heaters

Of these the most common by far is still the Atmospheric induced draft water heater.  These heaters require a combustion air source (vents) and elevation above the floor of 18″ to reduce the risk of ignition of combustible vapors (Gasoline, lint, etc.) in the surrounding air.  In addition to this the flue pipe must be secure with properly sloping run to the exterior and have a rain cap installed.   As a Leading Certified AZ home inspection specialist we certainly recommend hiring one of our ASHI certified home inspectors to evaluate the home’s plumbing and other systems prior to purchase for peace of mind.

 

For a full description of each kind see:  http://www.prospex.us/DOCS/PLUMBING/GAS-FIRED%20WATER%20HEATERS.pdf