does condensation on ducts in basement=bad install???

11 years ago

Yes, another new thread, because this is info other people might need and not really related to my other issues....

Spoke with the only neighbor who has heat pump. He didn't have a lot to say but did say that he now gets moisture on the ducts in the basement. He said it's on the cold air ducts and he has to keep the therm at 75 instead of 72 to reduce the amount. He has bought a dehumidifier as well. He had out a Bryant serviceman who did "something" to the thermostat and it got a bit better but still happens.

He didn't know the size but said they just put in the same size that he had... I'm thinking it is oversized. I got the feeling he thinks it is the heat pumps fault (not the size, but the way they operate vs non pump)

I was considering calling this company because they are the nearest Bryant dealer, not sure if I am close enough to the others. I wanted to compare quote to Carrier. Now I'm thinking maybe I don't want to call them at all.

One good point is I do know my sizes from the 2 contractors who came already and did Manual J. They would have to do one for me if they want my business. BUT, is the info from the neighbor a sign I should NOT even call them??

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Comments (9)

cindywhitall
Original Author
11 years ago
I forgot to say....this is the walk-out basement of a 2 story 2600 sq ft house. I don't think the basement is finished, but he did wall off the heater area he said. He has louvered doors on it and the repair guy said to leave them open.

We never had this problem at our house, even when the ac was new. Is it just because his basement is walk-out and is therefore probably warmer than my non-walk out? It would really stink to have that problem especially if you wanted to finish your basement....what if it drips and grows mold....
mike_home
11 years ago
It is not the heat pump's fault that the duct work is dripping with condensation. Actually it shows the heat pump is working very well in cooling mode. The air temperature coming off the coil is colder than it was with the old system thus producing more condensation.

Your neighbor has a basement with high humidity. The right way to fix the condensation problem is to reduce the humidity. He needs to seal off any outside vents and run a dehumidifier.
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cindywhitall
Original Author
11 years ago
He has gotten a dehumidifier. I wonder if his sliding door is leaky. If he has the same door we used to have in our family room it is probably not great. I don't know if he has any vents, there are none in my basement (same builder).

Glad to know its not likely the contractor. I have pretty much decided not to call others, but thismisone I was considering if I do.
countryboymo
11 years ago
I would get one of those indoor outdoor weather monitors and put the outdoor unit in the basement and see what the difference is and move it around the basement. I bet come caulk and possibly a caulk and foam combo would solve this issue unless a whole door needs replaced.

72 degree set temp makes me wonder if the system is oversized or if it is just pulling that much humidity upstairs from the basement.
cindywhitall
Original Author
11 years ago
countryboy,

I don't know what size his is, it looks pretty big though. It's the only heat pump I've ever seen and I don't know if they are bigger than plain a/c, but it is bigger than any of the a/c I have seen in this neighborhood. I will have to try to get the number off of it because I am curious. He said they just used the same size as he already had. I think it's weird because he apparently didn't have this problem before the new unit (new in about 2008--which is also weird as his old one would only have been 12 and probably worth repairing at that age)

I decided not to call his installer for my quotes......
Elmer J Fudd
11 years ago
Cindy,

You said:
"Yes, another new thread, because this is info other people might need and not really related to my other issues"

and then

"Glad to know its not likely the contractor....thismisone I was considering "

Now you're doing "I have this friend, she has a problem that she asked me to check for her.......".
cindywhitall
Original Author
11 years ago
Snidely, this time I am offended. I did mistype (iPad adds extra m's when not careful). I meant to write it was one I was considering. It is a Bryant heat pump and I WAS going to call a Bryant dealer to compare hvac prices out of the program. They had marginal bbb ratings so I knocked on a house in the neighborhood to ask how it went.

It's not the fictitious friend deal. If his install went great I might have called. Now I will just choose between the 2 quotes that I trust the contractor, I just don't want to pay their prices! Might be a case of you get what you pay for. This guy did say the company he chose was less $.
bus_driver
11 years ago
Having a dehumidifier may or may not mean very much. Knowing the relative humidity in the basement means quite a lot. I keep mine at 50% and monitor it at 4 places continually. Under 40% or over 60% would not be good at all. If the ducts "sweat" at 50% RH, I would definitely suspect the duct insulation.
weedmeister
11 years ago
The reason the condenser is larger may simply be that it is more efficient, not necessarily because it is a heat pump.

does condensation on ducts in basement=bad install???

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cindywhitall
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does condensation on ducts in basement=bad install???

Comments (9)

cindywhitallOriginal Author

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