Hvac height in garage

I am waiting a picture but I have a neighbor who has a gas furnace installed in a garage and has been told two things.
It’s a high eff gas furnace and they installed the return on the floor frames by 2x6 then installed a static ion filter on top of that then sat the furnace on top of this . The actual furnace is 19" above the floor.
Installer said it meets code of 18" off floor as the duct and filter don’t count as part if the unit. The service guy said its on the floor and even knowing the set up does not meet code of 18".
I always understood this was a combustion issue if a gas leak occurred and the service guy said its a CO2 issue which makes no since to me. Any insight ?

My understanding is its the source of ignition you are concerned about, not the bottom of the unit.

For 1 if he said Co2 you should not trust his decision. 2 he is dead wrong about the return air.
If it has a supply of air it can also work opposite and act to bring CO into the home from the garage along with explosive fumes from the garage.

Right but it does not matter where the return air is at… If it pulls air from the garage you have a problem. Seems height does not matter.
Juan, I agree on the ignition source height.

Return pulls air from the bathroom right inside the wall. The duct work is all sealed and the install is done very well. The combustion air is piped in through PVC as would be expected .

George than if you go by IRC Minimum Code R309.1.1 it will comply as long as there are no openings into the garage.
I will add however dumb to pull air from the bathroom.

Return air can not be taken from a garage a bathroom or a kitchen Nata no way

KW ya need to git ya chit straight before giving advice;-)

It is not being taken from the Garage!
According to what** he asked** I would not agree to take it from a bathroom. I am only stating what the Code says.
HVAC issue is not the same and is according to what you go by in your area.
You also are wrong about the return as many are installed that pull air from Bathrooms, Kitchens and get connected to a HRV or ERV. Do I agree with it? No!!!

You better go read and study some more you already have the Pope on your case ya don’t want this old man there also:twisted:

I am only going by HRAI guidelines. Pg 324 must have a removable filter installed in Kitchen.
I am only stating this that here you can have returns connected to the main return trunk to exhaust the bathroom and kitchen but in no way can you do this for a garage. The grill for kitchen must have a grease protector or be able to be cleaned the entire length.
It also gets interlocked with the furnace in most conditions.
Do I agree with it? No!!!

The OP was about here in the US not up where you live I don’t think George gives a crap what they do in Ca has no effect on him. Your not impressing anyone with what you don’t know.

Charley please inform me of what you go by if not the HRAI?
You are correct things are very different there so please share the link or reference you are using.
At a low location like what is being shown it would not fly here either. As I stated very dumb also and would not be allowed here according to HRAI guidelines.

I quote me I don’t go to any code book maybe the IRC if desperate I have been in this business for 40 years and a inspector for the last 17 overlapping my first career. I have lived and breathed this stuff since I could walk. I also have made some statements that were wrong but were corrected by my friends. But I am not wrong very often but when I am I admit it and correct it

I am not wrong this time in the US of A return air can not be taken from garages from bathrooms or from Kitchens peroid nada

Charley I am not here to question your knowledge that is why I stated what I did. I did not say you were wrong either!
I stated what is allowed here according to HRAI but only through the HRV or ERV, if no unit than it is a NO and also violation of the MVC.
As for returns in a bathroom as far as I know there is a portion in the building code on this.
at Section under Mechanical Ventilation that it cannot be recirculated. In a sense I think the reasoning of using a HRV allows this as it does not recirculate the air from bathrooms. The actual return you see in the OP is not allowed.

I did not see a actual return no PIC are you dreaming now, pic was to come later;-)

Oops! Two threads going.

Pics from unit. So charlie you say that it is not allowed to have return air pulled from a bathroom or kitchen? i knew garage was a nono… i want to get back to this guy and would like to understand why. Kitchen is explainable, fire, gas from stove pilot ect. Garage is self explanitory…but bathroom? what is the logic here?

thanks for all of the help!!!

I cant get the photos to load. Only one that loaded was the return pic…doesnt say much. I will email them to you charlie.

Think humidity.(might make exhaust fans obsolete as well :))
Kitchen is also humidity and grease to boot.(has nothing to do with gas)

Here George

Makes sense…