Compressor failing, or just bad recirc valve?

macgyvers2000

9 years ago

It's possible I posted about this issue earlier, but I couldn't find any threads, so I apologize if this is a repost.

5 years back we had our '70's-era HVAC system completely replaced with a Carrier Infinity system (the 19, I believe). Cool, crisp air. When I switched from heat to cool on the second year, however, the result was room temp (or slightly above room temp) air. Call service guy, he checks pressure, looks for codes, etc. No problems to be found... but it started blowing cold air when the system is switched back on. Hand him $100 and he goes on his merry way... I sit and wonder what the problem is.

Next year, same drill, another $100... getting miffed, but I have cold air again.

Following year, same drill, another $100... now I'm getting pissed. No problems can be found. I'm starting to wonder if the guy is pressing a hidden reset button and I'm helping to make his car payments :-/

This year, we had a power outage. When power is restored, we're blowing room temp air again. I do a few cool-to-heat-to-cool switches with no change in operation. I let it sit for a day with the power off, and when I turn it back on, cold air is back. I call the service guy knowing it could happen again.

It supposedly "acted up" while the guy was there. Unfortunately, I was not home to see what the issue was, so I can't even tell you what the pressure values were or what he checked.

I suggested it might be the recirc valve not switching over (bad solenoid?) or the relay controlling the valve/solenoid. That would explain room temp air coming in (if it's in the "heat" position), but not hot air, and when it does finally switch over, cold air is restored.

Service guy says it looks like a bad compressor (to the tune of $1500-$2000 in labor!... compressor should still be under warranty from Carrier). My question is, how can a bad compressor work quite well cooling the place for 5 years with its only symptom being a failure to start at the beginning of a mode switch or power failure? It still sounds like a sticking/faulty recirc valve or control relay to me...

Thoughts?

Sort by:Oldest

Comments (6)

klem1
9 years ago
You might be correct regarding reversing valve but it's unlikly. Compressor doesn't sound right either. There is a simple diagram inside unit if you know how to use a vom. Some compressors include a device intented to delay start as long as 5 minutes.
IMO,the customer deserves to be told what is/was wrong. Most will not totaly understand but that's beside the point.
macgyvers2000
Original Author
9 years ago
The tech said "It's not the recirc valve since I can manually switch it from one side to the other without a problem". I'm assuming he was shorting the relay to force it in one direction or the other, but that hardly proves the valve isn't a problem, it only proves that he can get it to move back and forth... if the solenoid is flaky, it may work just fine once it has become "unstuck". but once it "sticks" in one direction or another, it may take multiple attempts to get it unstuck.

Does anyone know if the recirc valve changes direction with a momentary signal, or if the solenoid has to be energized continually to be held in one direction? If it's the latter, what direction (heat or cool) is it typically in when not energized? If it requires constant signal (power on solenoid coil) for cooling, that would explain why a loss of power to the system often means a lack of cooling upon return of power... the valve returns to "heat" mode when it loses power, and getting power back doesn't guarantee a sticky valve will return to "cool" mode.

Just trying to understand potential failure modes here...
Related Professionals
Los Angeles Solar Energy Systems · Moorpark Solar Energy Systems · New Canaan Solar Energy Systems · Syosset Solar Energy Systems · Weymouth Solar Energy Systems · Brockton Home Automation & Home Media · Cutler Bay Home Automation & Home Media · Cypress Home Automation & Home Media · Hull Home Automation & Home Media · Thornton Home Automation & Home Media · Framingham Center Electricians · Channelview Fireplaces · Cypress Fireplaces · League City Fireplaces · Oak Lawn Fireplaces
klem1
9 years ago
Valve rests in heat position with no power required. It must have continus power to hold it in cool position. What you suspect can easly be tested with a vom.
tigerdunes
9 years ago
2nd opinion indicated from another dealer.

IMO
dovetonsils
9 years ago
The exact same thing happened to my neighbor. They installed a Carrier Infinity heat pump last fall and I saw a truck in front of his house on the first warm day this year. I asked him what happened and he said the A/C did not work and they replaced the reversing valve. That didn't make sense to me since this was such a cold winter here and I am sure the valve worked properly all winter for defrost (I didn't say anything).
weedmeister
9 years ago
Some are active in heat. Others are active in cold. Mine, a Trane, is active in heat.