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RyanHughes
12-02-2007, 06:39 PM
My heat pump has been nothing but problems lately. The first call began when it was toggling on and off and the compressor was cutting out. The tech found that a shaeder valve on the suction line was leaking and replaced it and charged the system. At this point I purchased a service agreement (luckily - read on). I had to call the company back out about a couple weeks later because the same thing was happening. The tech (whom I like) said the capacitor was bad, causing the toggling, and the freon had leaked out due to a leaking shraeder valve on the liquid line. I like how the tech was honest and said he probably caused it when he removed his gauges. This was Friday. The heat worked for two, almost three days until recently today, I noticed the compressor had cut out again and now I am getting cool air from the registers. I felt the refrigerant lines in the utility room to verify that the heat pump was not pumping. The fan on the heat pump runs, but the compressor does not. This is getting a bit strange/frustrating. The good news is the service agreement covers a lot; I did not pay anything for the most recent service call and won't have to pay anything for the next (as long as it's nothing major like a compressor or something). Your thoughts and experience are greatly appreciated for this matter. Regards.

Edit: Now the heat pump is pumping again (keyword now), but I'm almost certain this will continue. I will keep you guys posted. In the mean time, any thoughts? How big would a leak have to be for it to leak around 5 lbs. of freon in 2-3 days?

tinknocker service tech
12-02-2007, 07:03 PM
if your problem is refrigerant a leak that size should be easy to find. Maybe not so eay to fix tho

the key here is just what is wrong and why isnt it being fixed

RyanHughes
12-02-2007, 07:27 PM
Could it be in the lineset? I should have mentioned that a leak test was performed upon the first service call (soap bubbles) on the outdoor and indoor units, but not on a good amount of the lineset. Could the Lennox 13 SEER air handler that the Payne 10 SEER heat pump is paired with be causing these problems? I doubt it, but it's worth a guess. Thanks for the response.

RyanHughes
12-02-2007, 07:50 PM
Here is what I recently witnessed:

The heat pump started per the heat call, ran for a very short period, stopped, turn back on, and has been running ever since but with thick frost building up on the coil. Does this sound like it is low on freon? Could my compressor be dying? It sounds terrible... probably the worst I've ever heard it... very loud, too.

kenshvac
12-02-2007, 07:52 PM
Could it be in the lineset? I should have mentioned that a leak test was performed upon the first service call (soap bubbles) on the outdoor and indoor units, but not on a good amount of the lineset. Could the Lennox 13 SEER air handler that the Payne 10 SEER heat pump is paired with be causing these problems? I doubt it, but it's worth a guess. Thanks for the response.
next time you call them out ask for an electronic leak check it may be in your coil and that is hard to find with soap bubbles

orlandotech
12-02-2007, 08:03 PM
IMO the tech should have replaced both schrader valves when he found one of the original ones leaking or at least checked them real good w/ a sniffer. A 5 lb leak in 2-3 days is a decent sized one that should easily be found, maybe even by ear if in the right place. Mismatching SEER rated equipment only gives you a more expensive power bill than if the system was matched 100% The only way to find the leak is to seperate the lineset components and pressure test/ leak check with a reliable sniffer ( electronic leak detector ) . Evap coil, suction line, liquid line, CU needs to be tested seperately to see exactly where it is. I have had on occasion the flare nut on the liquid line at the CU develop a leak due to a lawn mower or HO disturbing it.

Good Luck with it.

orlandotech
12-02-2007, 08:07 PM
Here is what I recently witnessed:

The heat pump started per the heat call, ran for a very short period, stopped, turn back on, and has been running ever since but with thick frost building up on the coil. Does this sound like it is low on freon? Could my compressor be dying? It sounds terrible... probably the worst I've ever heard it... very loud, too.

It could be but maybe it's not properly defrosting, partially because of the low refrigerant level. He needs to check the defrost operation and check the coil sensors. The OD coil should not appear to have frost on it right after a defrost cycle.

RyanHughes
12-02-2007, 08:10 PM
He did test the defrost cycle; that checked out okay. I will have to take a closer look at it tomorrow when hopefully it's not raining and dark. In general, when a heat pump is low on freon, is the suction line going to be hotter? It's quite hot when the compressor is running. I will keep you guys posted. Thoughts are still more than welcome. Thanks.

badbillr
12-02-2007, 09:03 PM
I believe your problem lies in the bi-metal switch that has (2) pink wires coming from it & goes to the defrost board. I have replaced a few of these bi-metal switches on 10 seer Payne Heat pumps & Carriers as well. When the unit is in heat pump mode, eventually the outside coil begin to develope frost/ice on it, the switch clamps to an end loop on the outdoor coil. When the switch gets cold enough from the developing frost/ice, it closes the circuit path & after the pre-selected running time has been achieved ( 30,50,90 min.) it will allow the unit to go in to defrost mode. If the switch does not close, the unit will not go in to defrost. When he tested to defrost board, it only tests the circuits on the board, not the bi-metal switch. It basically ignores the switch & allows the unit to go in to defrost. But, in normal operation, if the switch does close, unit will not initiate the defrost cycle. Example - the board is set on 60 minutes ( yellow wire w/ pin connector) & the unit has been running for 45 minutes and is frosting over pretty good, the switch should close. Once it reaches 60 minutes of operating time, it sends a signal out through those pink wires, if the switch is closed it will then initiate defrost. If the switch is not closed, it will continue to run until the switch closes or the system cycles off, reseting the count down timer. Print this out and let the tech coming tomorrow read it. Hope this helps you out, I think it will. note- this bi-metal switch initiates defrost by closing & terminates defrost by opening.:)

RyanHughes
12-02-2007, 09:16 PM
Thank you for all that info Badbillr. I'll have to mention this. I think I know what you're talking about. It's two yellow wires coming from a small refrigerant tube I think.

AtticAce
12-02-2007, 09:21 PM
I believe your problem lies in the bi-metal switch that has (2) pink wires coming from it & goes to the defrost board. I have replaced a few of these bi-metal switches on 10 seer Payne Heat pumps & Carriers as well. When the unit is in heat pump mode, eventually the outside coil begin to develope frost/ice on it, the switch clamps to an end loop on the outdoor coil. When the switch gets cold enough from the developing frost/ice, it closes the circuit path & after the pre-selected running time has been achieved ( 30,50,90 min.) it will allow the unit to go in to defrost mode. If the switch does not close, the unit will not go in to defrost. When he tested to defrost board, it only tests the circuits on the board, not the bi-metal switch. It basically ignores the switch & allows the unit to go in to defrost. But, in normal operation, if the switch does close, unit will not initiate the defrost cycle. Example - the board is set on 60 minutes ( yellow wire w/ pin connector) & the unit has been running for 45 minutes and is frosting over pretty good, the switch should close. Once it reaches 60 minutes of operating time, it sends a signal out through those pink wires, if the switch is closed it will then initiate defrost. If the switch is not closed, it will continue to run until the switch closes or the system cycles off, reseting the count down timer. Print this out and let the tech coming tomorrow read it. Hope this helps you out, I think it will. note- this bi-metal switch initiates defrost by closing & terminates defrost by opening.:)

post. The frost build up is normal operation in cold temperatures, if however the frost turns to ice, or gets totally insane, then one could say the defrost is not working.

Feeling the pipes is not a good indicator of operation, as the unit could be in defrost. What might be responsible for the cold air is a defect in the back up resistance heat elements or control that brings them on. Check your filter!

A dirty filter, or other restriction of the air flow across the coil could cause your compressor to cycle off on high pressure, or compressor internal limit switch. This restriction of airflow would be akin to running your cooling in the summer with a cover on the outside unit.

I will make a prediction, after a few more (money losing) call backs you will be informed that your compressor is bad (something not covered under the service agreement). Hopefully replacing the unit will solve the problem.

Personally I like installing heatpumps in the summer, I however don't like to work on them in the winter. Having a tech do a through leak check in freezing weather is not going to happen. Most call backs we have are on heat pumps in the winter, I can't blame the techs, working on heat pumps are why I started my own business 26 years ago, just so I could say no service on frigging cold days. I tell customers to put it in emergency heat until it is safe to go outside.

RyanHughes
12-02-2007, 09:28 PM
The resistance heat is working. The outside fan continues running even if the compressor turns off. I'm pretty good with changing the filter, although I will check it (I don't think it's been too much over a month, but I will check it). I think my problem is the opposite of high pressure. :cool:

AtticAce
12-02-2007, 09:39 PM
The resistance heat is working. The outside fan continues running even if the compressor turns off. I'm pretty good with changing the filter, although I will check it (I don't think it's been too much over a month, but I will check it). I think my problem is the opposite of high pressure. :cool:

If the fan is running all on its own or does not cycle off when the unit is in defrost then the relay that controls the fan has welded contacts. One weird possiblity would be if one leg of the fan motor is shorted to ground, while the other is hot all the time, this can happen on one pole contactors. In this case the fan motor would be running on 115 volt. One would think on a call for operation this would trip the breaker, but then again not if the wire was not connected to the other pole.

Does the fan motor look like it is running slower than normal?

Is the fan motor turning in the correct direction? A bad capacitor can cause the fan motor to start in any direction, or to run backwards. I believe the tech did not figure out what was wrong on either call.
He was probably to busy freezing his butt off.

RyanHughes
12-02-2007, 09:42 PM
The capacitor was replaced on the last call after it was found to be bad. The fan seems to run normally, but it will continue to run when the compressor does not run. The fan turns off when it is in defrost mode. Earlier, the heat pump turned on then shortly later cycled on and off and continued running. I'm not sure, but it's been having very strange behavior ever since it's gotten cold out it seems. Over the summer it worked great. I'd like to change out the whole system with a matched one that's quieter and more efficient, but if it's not 100% needed and I can have this heat pump repaired, I don't think I can do it. The heat pump is from 2004 and the air handler is from this summer. I can't take the temperature of the air coming out of the ducts now since I gave the technician his thermostat that he left here the call before back, but from what I feel it is not at all as warm as it should be. :eek:

BigJon3475
12-02-2007, 09:50 PM
You said this is a PH10 correct? When it cuts out do you hear aloud switch. The PH10'sI work on make a very audible click when the low pressure kicks out if that's what you think it is.


Normally it going out on low pressure it won't come back on unless the switch is bad and getting stuck. If it's low on ref. it could be cutting out on thermal overload. Again it wouldn't normally start right back up until it cooled off. Is water steaming off the top of the compressor rapidly when it cuts out? You shouldn't be going out on high pressure unless your fan isn't moving enough air, filters clogged or coil is clogged. You have a bigger inside coil than would be recommended (13 SEER correct?) It should easily be able to reject the heat as long as you have the correct airflow.

It could be a loose connection or low voltage. Do you have a cycle protector on it if you know? I'm leaning towards something electrical causing it to cycle and then shutoff for the given period that is of course if it isn't a leak.

RyanHughes
12-02-2007, 09:54 PM
PH10JA042-C I think (off the top of my head). I don't ever recall hearing an audible click. I am questioning if the bad capacitor really caused all this since it is happening again with a new capacitor (not to say the bad capacitor didn't contribute to the issue). I have confidence in the company I use and the technician, but I feel like calling them back for yet a second callback after they were just here Friday is a bit annoying. I'll take a look at what it's doing tomorrow and see. Question: does all of this sound like a bad compressor, low freon charge, or something out? If any of you guys have a notion of what the problem may be, please let me know. The compressor makes a horrible noise when it runs... like a somewhat high-pitched grinding. The Payne is loud as it is, but this sticks out. By the way, when the contractor did his final check on his gauges, I was standing there. I saw somewhere from 50 to 60 on the low side and somewhere from 150 to 200 on the high side if memory serves me right. Also, he mentioned an 8 degree superheat reading on the service sheet. Does any of this impact your thinking? Somehow the house is staying 70 (with the heat pump running a lot) without the use of auxiliary heat to help. I'm guessing this is just luck from the system sometimes blowing warm enough air to maintain 70.

AtticAce
12-02-2007, 10:55 PM
be replaced already?

What was the reason for your original call to the service company?
A bad run capacitor could be possible as the 370 volt caps seem to have a very short life, but that was changed on the second call.
The freon leak was caused by the tech. You stated a bad shraeder, this would not have caused a leak if the service cap had been installed properly. Assuming the cap was installed properly, there was no leak mentioned at that call, yes?.

Noise is caused by liquid slugging, or overloading of compressor. I would look to that new air handler as the possible cause of the problem. What is the temperature change before and after the coil? Is the airflow out of the ducts normal? Have the tech measure the pressure drop over the coil.

Payne units are bottom of the line, they have no sound proofing, do not confuse the sound of winter operation with the sound of summer operation, they will be different.