Saw this on a brand new build. The HVAC condenser is installed directly under the microwave vent. Is there anything saying they can’t do this for Backdraft reasons? To me it seems like the condenser would push the vented air from the microwave back into the interior of the home or possibly cause the damper to stay
open when the microwave is not in use. Just curious if anyone has ever encountered this or if there’s anything from the Florida building code or international residential code that says this is not allowed.
Brand and Model number please.
While there are clearances for HVAC condensers to wall surfaces and what terminates on wall surfaces and object clearances, to state ‘condenser would push the vented air from the microwave back into the interior of the home or possibly cause the damper to stay open when the microwave is not in use’ is a different matter. The wind/weather and/or imbalanced interior pressure should not be able to enter the kitchen stove top venting. That kitchen vent, stove top exhaust vent damper should one directional.
As for the HVAC condenser clearance. If I remember correctly, 5’ feet to exhaust vent wall terminations but falls under Manufacturers recommendation.
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Personally, I don’t see a problem with that set-up. From here it looks like the vent termination is too high for the condensor fan too have any effect on it.
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This seems like a very simple experiment you could have performed while you were at the house. When you did this what happened?
Do you put assumptions or theories in your report or actual defects?
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Testing residential exhaust vents.
1: Perform a simple suction test with a piece of paper or use a flow hood or anemometer to measure airflow. A piece of tissue paper will move in the direction of flow and be static when there is no air flow.
I see no condenser clearance issues myself.
When I inspect HAVC condenser equipment I physically try to move the condensing unit. It should be physically secured to a permanent base with a mechanical damping device, yet allowed to vibrate. The physical vibrations to the base should not disperse into the structure. The overall design, should incorporate vibration isolation techniques.
Level. Is the unit level? I use a level. I look from all angles. Back to front. Side to side.
Then I move to obstacle clearances.
A minimum of one foot (12 inches) of clearance should be maintained on all sides of an HVAC condenser unit for proper airflow, with some manufacturers recommending up to two feet. Additionally, a minimum of 60 inches (5 feet) of overall vertical clearance is needed above the unit. This ensures efficient operation and prevents overheating.
Exterior units condition.
Operational condition in the home.
Hope that helps.
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Could you see the damper? Any air movement back towards the interior of the home would be restricted. The damper lets air out, not in.
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The range vent and others have a back draft shutter.
Did you test for back draft? If not, it is a non-issue because you don’t know,
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Non-issue. When the fan is on, it’ll force air out, when it’s not, it’ll close the shutter.
I’d also be shocked if you held a tissue paper near that while the condenser was running if it’d even move much at all.
FYI, one of my listing agents sent me your summary report on 6581 Mason as I do some repairs for listing agents. i’m going to be doing some caulking and irrigation.
You can just call out missing splash blocks. 
I do all the time, no need to get a professional.
Also, for what it’s worth, if there is a detectable gas leak, you should flag it for immediate testing by Teco. They will come out very quickly. I’ve done it a handful of times. If they aren’t there by the time you leave, turn the gas off.
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Sorry for the late response. So the damper looked like it was being held open when the condenser was blowing which is what prompted my question. Turns out it was just getting stuck because the mesh cover for it was dented inward. I always like to ask while I’m at an inspection and check responses as I go. Ty for all the responses!
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That would be an obvious problem for it defeats the purpose of the damper.
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No to worry about the late response.
Any good images of the range hood termination vent on the exterior wall?
The range hood exhaust termination vent damper should be closed when exhaust air is static. In other words; when a range hood fan assembly is inactive, the circuit turned off, the damper door should have closed prohibiting outside fresh air, and critters, from entering the vent, & ductwork therein.
Any mesh or screening should be that of the manufacturer. When damaged it should be reported. When damper door is stuck open, it should be reported.
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Good call. I’ve had several that were just jammed up with “goo” and dust. If I’m there, it’s easily reachable and I can just work it free, I will. If it’s mangled or something though, I’ll call it for repairs.
So did you inspect the duct material? I find this at least once every month or two on new builds.
In case you don’t know what you’re looking at they have used aluminum tape as duct material between the elbow and the damper fixture.
I had a house this month they didn’t even use tape. I could stick my whole hand into the kitchen cabinet.
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Morning, hope to find you well and thank you for the image, Donald. Greatly appreciated. I will be back to this same string once I analyse the image.
My first thoughts are it is an original exterior galvanized steel exhaust vent partly encased in stucco, that has been damaged and is not properly aligned, not square, on an angle. Likely mechanically damaged.
That may cause the damper flap to snag on the side of the cabinet and remain open.
The vent screen appears dislodged from its original position.
Be back shortly.
So here is what I found so far. I spent about 5 minutes creating this illustration.
Material degradation.
Mechanical damage. Twisted vent hood cabinet/body.
Displaced vent cabinet screen tp prevent critters from entering. Likely caused from the mechanical damaged.
Damper door appears hung-up on twisted cabinet and/or the screen.
Hope it helps.
