How to install a draft hood on the standard-type atmospheric gas water heater.
Every gas-powered water heater that utilizes the atmospheric venting is equipped with the draft hood, an element that is found on the top of the heater connecting the unit's flue exit with the venting system.
Its role is to direct products of combustion safely from the heater to the venting system and out.
Depending on the model, the draft hood accommodates 3" or 4" vents or combined and is designed for single or double-wall vent (galvanized) pipes.
In a case of the double-wall vent pipe, the recommendation is to install the Type B draft hood connector. A vent pipe connector should also be used if the vent pipe has a larger diameter than the draft hood.
Also, two types of the draft hoods are found; lock-in and push-in types. Both types are easy to install; the first one uses the slots so the draft hood legs can be securely locked-in, while the other one is secured with the self-drilling screws (usually provided). If the screws are not provided, the recommendation is to use 5/8" long screws or shorter. Three screws, evenly spaced work the best.
While installing the
draft hood, it is a must to secure the connection, which shall also be
airtight, so no flue gases can leak. Some adjustments might be needed
as long as the original size and shape are kept.
The draft hood installation must be done per manufacturer instructions and codes.