ECN Forum Forums Photo Discussion Forums Violation Photo Forum AC Unit Installed on Roof Top

I guess some people just don't believe in "workmanlike manner"

Monday I am going to a job with a contractor who is bidding on work. Part of scope is replacing the A/C rooftop units. I have been there in the summer (lots of bees) and now I will get to take pictures of the 'mess' with snow on the roof. The units look a lot like this photo.

Pierre

I think what Joe was referring to was the proximity of the condenser unit to the vent in relationship to disruption of air flow.
Being that close, it may be possible for the volume of air being pulled in the side of the unit, and the air discharged out the top, may interfere with the proper operation of the vent. Per IRC 2426.6.5 and UMC 806.4 the vent has to be 2 feet above anything that is within 8 feet of the vent. If the vent was there first, then the condenser unit was installed too close.

Am I on the right track Joe?

Mean Gene
isn't that the condensor?

I went to the job to look at the rooftop A/C units. I got some good pictures of the units covered in snow to go with the summer pictures I took. Now I will try to send both to Joe so you can see the two scenes.

Pierre

Mean Gene:


Yes, I was wondering about the vent and its discharge.

Pierre, I will look forward to the pictures.

That is a condensor unit, and does not suck air into the living space. How would the location of the vent otherwise affect the installation?

Pierre

I think they are saying the condensor installation may affect the performance of the vent. Turbulance, positive pressure, or blowing back down the stack could hider it's ability to function properly.

But why would that be any different than a windy day?

Well, I was presuming that the reason that the building codes said the vent had to be 2 feet higher than anything withing 8 feet of it was for proper air flow/operation of the vent.