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Heating & Air Conditioning

Intermittent condenser on heat pump

3 years ago

Rheem heat pump, every few days when the the thermostat calls for AC the blower turns on, but the outside unit does not. Dropping the thermostat one degree, the outside unit will kick on and work fine for many cycles. Technician came and replaced capacitor and contactor which has not fixed the problem. Swapped out upstairs and downstairs thermostats to rule out faulty thermostat. Condensation drain is cleaned out and flows. Lights on defrost board indicate normal operation. Problem seems to happen late night or morning, but that may/not be accurate/relevant. Technician suggests possibly replacing board on internal unit, but I'm not super confident in diagnosis. Any thoughts?

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Comments (4)

PRO
Austin Air Companie
3 years ago
last modified: 3 years ago
Intermittent problems are like chasing ghosts sometimes.

Chasing ghosts = guessing what is wrong. What would you do if every time you went somewhere the system was working, but the customer is saying there are times where the system doesn't come on?

The logical steps are doing what this tech did. (Doesn't mean the guess will be right -- if the system is working when the guess is made) The more brash approach would be to sell you a completely new system.

How old is this HVAC system?

Given you have 2 thermostats and one unit, that is a zone system... that only complicates things further. Plenty more parts to guess at....
Paul G
Original Author
3 years ago
I believe the units are 2007 — so I know they need replaced but have been reliable. There are two units, one upstairs and one downstairs. The downstairs unit is the issue. Not sure exactly what the tech checked when they were here, but said refrigerant and compressor seemed fine..
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PRO
Austin Air Companie
3 years ago
2007 is getting up there but not uncommon to repair a system this age.

Intermittent problems: It still doesn't change anything in terms of finding an intermittent problem. Unless the tech / contractor happens to be there when it's acting up.

I have a good spidey sense when it comes to such things... but I leave my guessing to in person calls that are paying me to do my job. (This forum doesn't pay me)

Maybe a home owner with too much time on their hands will chime in?

I service the Katy, Texas area.
sktn77a
3 years ago
last modified: 3 years ago
"I have a good spidey sense when it comes to such things... but I leave my guessing to in person calls that are paying me to do my job. (This forum doesn't pay me)"

So why do you come here?

"Maybe a home owner with too much time on their hands will chime in?"

Maybe a "Pro" with too much time on their hands and nothing to offer?

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