Hi,

I have a water heater in an exterior enclosed closet space approximately 4 feet x 7 feet. Plumbing code requires two vents for air with one commencing within 12 inches (31 cm) of the top and one commencing within 12 inches (31 cm) from the bottom of the enclosure.

My enclosure is stuccoed already so it will be hard to modify it for a vent at the bottom. The easier way for me to make a vent at the bottom would be to start it about 16 inches from the bottom. I will be breaking code but is there any other problems that I will encounter if I start the vent at 16 inches above ground? Like would my pilot burn out..etc?

Thanks!!!



Edited 1 times.

And where will it drain to, when it begins to leak or the T&P valve, goes off.
Best Wishes

Can you put the vent in the door?

code requires 1 sq inch per 1000 BTU of the appliance.
so if the water heater is 40000 BTU then 40 sq inches is required.
BUT the minimum requirement is two 10 x 10 grills. do the math and that is 200 sq inches. 5 times as much as you need but nevertheless required. so there is no way you will be starving the heater for make-up air..

A 10x10 grille does NOT have "one hundred square inches of vent area". They only count the area of the openings which could be 50% to 75% of the total area. If you have an attic, you can also install the vents, one low and one high, using ductwork into the attic.

vrai...

Is it too late to consider a direct vent water heater? It would not require modifications to the enclosed space.

A 10" X 10" return air grille is actually 11-3/4" X 11-3/4". The 10" X 10" dimension actually refers to the vented portion of the grille. "Free air" will be less than 100 sq. in.