Water Heater Air Gap

How an air gap works.

Water heater air gap.

What a great idea for attic installed water heaters. If the temp gets to high the water expands and gets pushed out before the tank overpressurizes. An air gap is the most simple and effective means of preventing contamination of a potable water supply. Once potable water leaves the outlet of a fixture it s either used or sent down the drain.

Gravity pulls it downward into the hose which carries it to the garbage disposal. The air bubble in the water heater is created when filling it. In a properly functioning air gap the dishwasher hose attaches to an input on the air gap and the water is expelled out the end. It is possible to overfill the tank if you fill it quickly and have the pressure relief valve.

The air gap avoids such problems because the pressure at the outlet of the heater only depends on the heater itself and is independent of the particular chimney configuration. The instructions that came with the water heater say to leave a 6 air gap between the temperature and pressure pipe and the floor drain. The gap where the water falls downward through the air instead of a hose functions to prevent siphoning and. Proper venting prevents backdrafting.

Imagine if that water heater quickly relieves 50 gallons of 140 f water onto the drywall ceiling of a bedroom over some sleeping occupants. I have a pan under the wh and if the discharge pipe came to within an inch or two of the pan i think more of the water would go into the. The pressure relief valve at the top of the water heater is supposed to be sitting in it. Discharge through a visible air gap in the same room as the water heating appliance.

Code expert glenn mathewson describes 10 common water heater code issues including confusion about drip pans and drains unsupported expansion tanks and plastic vents lack of combustion air and more. In the event of a drain back up or flood the contents of the drain line should never be able to make contact with the water supply the two. 1 the discharge pipe cannot be directly connected to the home s plumbing drainage system but an air gap located in the same room as the water heater can used to connect to the drainage system. The most common problem associated with water heater venting is a condition called backdrafting in which exhaust gases from the water heater fail to exit the home via the vent and instead end up in the house backdrafting can have many causes but it is most commonly due to poor vent design or installation and or an imbalance of air volume in the home.

Installing a tank water heater might seem easy but homeowners who refinish their basements often create a number of code violations with respect to the water heater. So long as the chimney is at least a couple of times larger than it needs to be the system will find a natural balance where amount of air drawn in increases until. The water heater that was first installed in the house was like that too.