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kling65
29-04-2008, 04:24 PM
Is there anyone out there that has had problems with reversing valve sticking on Amana heat pump? I installed one it it ran good through the winter (4 month), and than the reversing stuck in the cooling mode. The heat pump is a 3ton unit with R410A and has a Copeland Ultha tech scroll compressor. I have heard from another dealer (technician) that there has been a problem with them ??

nike123
29-04-2008, 04:55 PM
Hit valve with rubber hammer few times and change operation mode after that. It may help.

The Viking
29-04-2008, 05:26 PM
Normally when reversing valves get stuck, it's because there is "grit/impurities/sludge/crap" stuck in it's slide.
As Mr 123 pointed out, 9 times out of 10, you will be able free it by tapping the end of the cylindrical body with a hammer.

But, the more important questions that often are overlooked...
What is the state of the system?
Why is there any impurities in there?
What will the long-term effect be on the system?
Were good engineering practices followed when the system was built and installed?
(Half of that last question you, as the installer, would know the answer to but the other half only the manufacturer's assembly workers will be able to answer)

andy c
29-04-2008, 08:15 PM
Have you checked that you are getting the correct voltage at the coil, more often than not it is the coil voltage at fault. It only needs to be a few volts short for it to cause such problems. I think i've changed one, maybe two valve bodies in 20 years, due to sticking sliders. Regards, Andy C.

HVACGod
29-04-2008, 08:33 PM
Kling if I may, I would recommend some of the articles on this blog: http://wayneshirley.wordpress.com/2008/02/07/troubleshooting-heat-pump-systemsreversing-valves/ some very comprehensive heat pump specific articles here.

EdC
04-05-2008, 03:37 AM
its certainly not a good sign.
I'll go out on a limb here, that system has
bigger troubles to come.

dsp
04-05-2008, 07:07 AM
Do you have a strong cylindrical magnet? You can get them from most wholesalers. I usually give the valve a tap with a hammer to loosen the slide. Then I slide the magnet over the stem a few times to loosen it up before operation.

I agree with the above statements I think you may be in for more problems to come.

dsp

Argus
04-05-2008, 03:23 PM
.

Reversing valves are operated by a servo mechanism at the solenoid that translates the compressorís discharge pressure into the force that moves the internal piston assembly.

You may have a piece of debris small enough to have travelled past all the parts in front of the valve (the compressor, usually) but large enough to foul it so that it sticks in one position or another. Thatís a tall order. If so, change the valve.

My experience in these cases is that the valve is not receiving sufficient pressure to operate the piston assembly. They generally need at least 100 psi (about 6 bar) from the compressor. Otherwise they will stay in the rest position.

I would suggest that you check that the compressor is pumping properly and that there are no blockages in the suction side before tearing out what is probably a perfectly good valve.

.

OAT99
23-05-2008, 06:46 PM
I agree with 123 and the others that tapping the valve on the linear side may get it to move, also check the solenoid and it's connections. Most of my experiences on older units is to change out the valve and solenoid. This unit seems to be fairly new,check your operating pressures and consult the manufacturer, you should have a warranty.

Larry2
03-06-2008, 05:26 AM
If I were the customer on a unit this new and it has a reversing valve issue that is more significant than an open coil or control failure, I would be asking for a new one from stem to stern. Trouble here so early says there is problems with the installation or the manufacturing process.

jmojacksonville
26-07-2010, 12:22 AM
My Lennox is 5 years old. Since a snake crawled in to my unit 3 years ago I have had the coils replaced twice once because of the snake and the next was because the coils got recalled for corrossion.
A week ago, my unit that runs almost constantly in FL started putting out hot air. I shut it off and tryed recycling it but to no avail. Everything seemed to run normally so I went outside and pounded with my fist on the unit and it hissed for a moment and worked perfectly. I called service and they said that the reverseing valve sticks and the unit will not go into heat mode in the fall. They want to put in a new reversing valve (warranty) and flush the system out for about $1200 bucks. It happened again today and a rap on the top of the unit fixed it again. If the valve has been in the cool mode all week and the power did not go off, why did it switch modes if it sticks? My air conditioning is working at peak performance since it has been refilled 3 times, 2 with the new coils install and 9 months ago a lead coming off the compressor leaked was repaired with a refill and it has a new fan motor and blade. I've got to think that something is makeing it switch or makeing it go to the nutral position. What does anyone else think?