Last year the owner finished off 1/2 of the 1st floor as living space and added a 2 ton split system for cooling.
Now the garage is on the left and the living space is on the right side.
They added a small extra bathroom on the far left corner of the garage and only ran a supply air duct with no return.
Shouldn’t this space have a return to function properly?
The job was permitted with the county (but this may have been added after the permit was signed off):roll:
The extra bathroom was cool.
Left side Center non a/c Right side
_____| GARAGE | NEW FINISHED LIVING SPACE
(Mike Auger, CMI - RI 32856, RMC-142, RMB-096)
The living space should be separated from the garage space, fire and air exchange wise. I’ve seen finished basements with no return, I always comment about it, but sometimes installing return ducts is cost prohibitive (not our problem to figure out), but certainly mention it in there too.
That is exactly what I am saying no return installed from any bathroom. If the bathroom was within the home or the conditioned area yes it would draw a return from under the door but would be mixed with a % of other return/ or conditioned air.
In your diagram being its strictly a enclosed bathroom in the garage no return is allowed and the supply air is just wasted as it is just like blowing air into a bottle until the bottle gets full then it overflows any where there is a opening. In your diagram the room will cool and heat somewhat because the room pressurizes enough for the air to escape into the garage area where it is just wasted energy. A typical case of someone not having a clue what they were doing.
Does the bathroom have a self closing self sealing door.? What prevents the door from being left open and CO or other fumes from entering the living space via the duct? I believe a jumper would help. How are they running this duct all the way over there.? Hopefully not exposed flex through the garage.