H.P. defrost cycle

Can anyone tell me if the condenser fan should run when the HP is in defrost cycle. It’s a 5 yr old Goodman 2 1/2 ton.

No. It should not run during defrost.


Is this a test?

Why should it not run, or why isn’t it running, or why is there a defrost cycle, or how does the defrost cycle work, or why is this inspector inspecting things he does not know anything about?

The condensing coil fan (inside) should be on during defrost and the evaporator coil fan (outside) should be off during defrost; that is the way mine works and its a Goodman about 5 years old.

Why :D:D:D???

If the fan of the outside coil was on, the coil would not defrost…

Why :D:D:D???

Fan pulling cold (freezing) air through the outside coil which is trying to melt accumulated ice…

Good answer thank you

Ok answer this, if you answer correct you will win one smiley face.

A HP reversing valve is controlled by a 24 volt holding coil, What mode does this holding coil become energized and how do you know if the holding coil has failed by simply operating the unit from its thermostat. This question will have a follow up question think about what the next question would be.

Show me what ya got;-);-);-);-);-):shock:

The holding coil become energized in AC/defrost mode. Switch the thermostat to AC and you should hear the reversing valve being activated.

Heck, its loud enough to wake up the dead when it goes into defrost…

No smiley face:(:frowning:

Marcel ya had it backwards the holding coil is energized on the normal heat mode and de-energized in the defrost and normal cooling mode.

When operating a HP in the normal heat mode and if the unit stays in the cooling mode. The compressor and the outdoor fan operates giving the visual appearance that the unit is operating normal. One must feel the big copper (suction line) and if it is hot, very very hot then the holding coil for the reversing valve did energize.

If you switch the stat to emergency heat then the holding coil de-energizes back to normal cooling position, then the back up heat activates. The compressor and the outdoor fan is not in operation in the emergency heat mode.

I will give ya a smiley anyway:D but only one;-)

*2. A defective solenoid coil will not energize the valve in the cooling mode. (Some manufacturers energize the valve in the heating mode, make sure you check). This can be determined by using the voltmeter and screwdriver test outlined above. If there is voltage to the valve and no magnetic field present, the coil has an open circuit. In this case, only the solenoid coil needs to be replaced.

Above copied from: http://www.hvactrainingsolutions.net/troubleshooting-reversing-valve/

As if I’m going to go check, its -15 outside…

I have never seen one that energized in the cooling mode.:shock:

:-k Around here the orange wire (normally used) is energized in the cooling mode, blue energizes in heating mode. The terminals in the thermostat are different so they can be used on any unit.

In defrost, the coil is energized/de-energized to put the unit in the cooling mode with the OD Fan off and EM Heat on (if installed).

Q2: what could cause the valve to not change, even if the coil is good and is energized?

I will give ya a smiley anyway:grin: but only one:wink:…

A stuck/defective valve.

I wonder what MFG energizes the valve in the cooling mode as your link stated I just have never run across one. It must be so if on the internet:p