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CHARLIE VAN FLEET
10-17-2009, 03:33 PM
hey all

new home. i know dryers should not be vented near ac units, but also believe hvac should also not.what do you think about this. left is high efficient furnace,,right i don't yet, have not been in house yet

thanks
charlie

Markus Keller
10-17-2009, 04:00 PM
Assuming a typical install, meaning one pipe is vent and the other is combustion air, I wouldn't have a problem with the one on the left regarding the AC unit. However, depending on which pipe is which it could be a problem. For instance if the left pipe is vent then it is blowing directly towards the right pipe which is combustion. Would it be a problem? Unlikely since the combustion air side isn't pressurized (sucking) just atmospheric. If the left pipe is vent then over time the paint might peel off of the right pipe.
As for the right set of pipes those are a problem. Assuming one pipe is vent it will be blowing the acidic/corrosive condensation mist directly at the AC unit. Overtime this will likely lead to corrosion. From what I've seen it won't take long, a year or two.
I would right it up to change pipe direction on "both" vent pipes.

Jerry Peck
10-17-2009, 05:19 PM
Because of the corrosive action Markus mentioned, I would write them up as needing to be routed to a new location away from the condenser units and discharging even further away from the condenser units.

Also, is that left condenser unit pad about to toboggan down that little hill? Kind of looks like it is head that direction.

Are those condenser units level? The both look off level, especially the left one ready to take off down that hill.

Are they far enough out from the wall to not be under the roof run-off?

Also looks like the service access panel might not have the required 36" working space? Depends on where the electrical is once those panels are removed.

Also, being on those vents are likely for heaters, it is unlikely that both the heat pumps and the furnaces would be running at the same time, otherwise there could be an interaction between the heated air discharge from the vents and the condenser units (other than just the corrosion mentioned above).

Are those condenser units anchored down?

Those pads look like flotation devices instead of concrete anchoring pads.

Markus Keller
10-17-2009, 05:26 PM
Nice catch on the lack of earth under the front of that left unit Jerry.:) I missed that in the pic. I was wondering about the electric and freon lines. Is that real stone on the walls or some faux stuff? Seems like drilling and sealing nice holes in that is going to be rough.

CHARLIE VAN FLEET
10-17-2009, 05:34 PM
THANKS GUY--wrote up the tobogan--they will be landsacaping so made that clear to client. units are away from overhang and they are missing utility caulking, wrote that up to. can't wait to see what those other vents are--the one on right side.

thanks