# Lennox Heat Pump shuts down



## Master of Cold (Aug 7, 2011)

Well first off your low on charge. Which will trip the thermal overload in the compressor. The fan not running is an indication of a defrost board problem.
You can take the black wire out of the relay (the thicker one) and put it on the top of the contactor, with the other black wires. This will bypass the relay and let the fan run. 
You ned to have someone come out and find the leak, or at least charge it back up.


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## beenthere (Oct 11, 2008)

Is the condenser fan spinning backwards?


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## sully2 (Aug 14, 2011)

the fan is shooting the air up wards out of the condensing unit.
My neighbor who supposedly does ac work for a living looked at the gauges and said the charge is good. I just looked at the chart on the inner panel, and it says for r22 the hp036 should be 78 on the suction side. is 65 low enough to cause it to keep shutting down?

The unit always trips off around 3-4 am when the ambient outdoor temp gets close to 78 where the thermstat is set. like it wont come back on after it cycles off.

last night I found one of the 2 thermals overload sensors was a closed circuit. the sensor looks a bit warn out. I unhooked it from the board where it was plugged into "OF" and "PF". I'll replace that in the morning.

@Master- the condensor fan runs whenever the compressor decides to run. I'd rather not bypass the contactor. Thanks Guys


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## beenthere (Oct 11, 2008)

How hot was it outside and inside when he checked the pressure. SH and SC would tell whats going on with the charge, pressure doesn't tell you much.


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## Doc Holliday (Mar 12, 2011)

I have the same problem on the same Lennox. The board in the condenser led one is solid meaning board failure. I have pi
cs ill post in a bit.


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## Doc Holliday (Mar 12, 2011)

It has call to board and 240

 volts but not coming on.


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## Marty S. (Oct 31, 2009)

Doc the only thing between the board and contactor is a high pressure switch. Double check the code because one solid and one off is also a high pressure lock out signal. Pull R from the board for a few seconds to reset the lock out.


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## Doc Holliday (Mar 12, 2011)

Tunis Marty. I saw the legend and that was what it coded, led one solid meaning control board. Failure. So that's what i diagnosed it as.
I'm not familiar with heat pumps. Ill post the pic i took. Of the board with solid. Led one and legend when i get home.
Thanks Marty.


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## Doc Holliday (Mar 12, 2011)

Tunis? Too funny! Thanks.


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## Master of Cold (Aug 7, 2011)

There is a low pressure, and high pressure option on the board. Switch may or may not be there depending on the unit.


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## Master of Cold (Aug 7, 2011)

Also..lennox residential boards have a terrible failure rate. Try grabbing the terminal block and twisting it.


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## Doc Holliday (Mar 12, 2011)




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## Doc Holliday (Mar 12, 2011)

Led on left is one: legend which might be unlegible states led one (or two) solid board failure.


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## Doc Holliday (Mar 12, 2011)

And as you can see there is nothing between the call and the board. The call goes straight to and through the board and comes out the other side. There might be a pressure switch between the board and the high voltage fan/compressor "on", but I'm not sure. 

Thanks guys, I can certainly use the help.


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## Master of Cold (Aug 7, 2011)

That's where the bullet needs to go..straight through to the other side..


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## Master of Cold (Aug 7, 2011)

All right looky here.
Take the wires off of the board that go to the contactor.
Put one side of the contactor on the yellow thermostat wire. The other wire off of the contactor, connect that to the wire in the "c" terminal. Pull off the two wires that go to the reversing valve. Connect those to the "c" wire and orange or "o" terminal. That will get it running. After that you can find a board.


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## Master of Cold (Aug 7, 2011)

Oops...take the wire from the fan (black), out of the black relay. and put it on the top of the contactor...


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## Doc Holliday (Mar 12, 2011)

The board and a new stat which was recommended by Lennox when replacing defrost control boards is on will call.

Now finding the time to get to it is another story.

Thanks.


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## Master of Cold (Aug 7, 2011)

Have them mail it to your house.


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## Doc Holliday (Mar 12, 2011)

Master of Cold said:


> Have them mail it to your house.


 
Who, Lennox? They'll do that?


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## Master of Cold (Aug 7, 2011)

Yes. You will have to givem them a cc over the phone, and cover shipping costs.
Im actually surprised they had it in stock. What state are you in?


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## Doc Holliday (Mar 12, 2011)

Master of Cold said:


> Yes. You will have to givem them a cc over the phone, and cover shipping costs.
> Im actually surprised they had it in stock. What state are you in?


If there's a fee then I'm sure my boss will not be interested in paying it. I'm Houston, Texas, the hvac capitol of the world meaning more refrigeration and air conditioning systems per square mile than anywhere else on the planet. Every manufacturer there is is here, their distribition plants are the size of air plane hangars.

When I was on the phone with First American Home Insurance the other day they asked me if I'd like the txv for a three ton Carrier shipped to me, no charge. It's being sent to the office.


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## beenthere (Oct 11, 2008)

Doc Holliday said:


> If there's a fee then I'm sure my boss will not be interested in paying it. I'm Houston, Texas, the hvac capitol of the world meaning more refrigeration and air conditioning systems per square mile than anywhere else on the planet. Every manufacturer there is is here, their distribition plants are the size of air plane hangars.
> 
> When I was on the phone with First American Home Insurance the other day they asked me if I'd like the txv for a three ton Carrier shipped to me, no charge. It's being sent to the office.


Because if they provide it. Then your company can't mark it up and make money on them on part m ark up.


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## Doc Holliday (Mar 12, 2011)

beenthere said:


> Because if they provide it. Then your company can't mark it up and make money on them on part m ark up.


 
We don't make our money on mark up, not through insurance companies. How it works with insurance companies is they pay for any and all mechanical parts that can and do fail. They pay our labor, all of it. When I'm at a home and I see things that need to be done such as insulating the suction line outside cause it's dry rotted and the low side is exposed or there's no float switches or drain pans that are rusted out (not a mechanical failure) then we do that work, upgrades.

Here's one I did yesterday that took me 20 minutes, rusted drain pan changeout and installed two float switches. I called the insurance company on speaker phone while at the home owner's place to verify that they do not pay for any of that. The home owner's called due to water dripping from their secondary outside. They had no water protection and thier were holes right through the pan.









What it looked like on the inside fo the evap.









Blurry pic but after.


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## Doc Holliday (Mar 12, 2011)




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## Doc Holliday (Mar 12, 2011)

When I do a compressor or an evaporator there's piping modifications or plenum modifications that mostly are non covered. All of that goes to our overhead. When a home owner has the highest level of insurance, the platinum, then they're covered, disposal, recovery, mods, whatever. We just bill the insurance company.

For jobs outside of insurance we do it like everyone else does, you know.


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## beenthere (Oct 11, 2008)

Generally they aren't insurance companies. They're warranty companies.

Insurance pays to repair damage. Warranty pays to repair breakage.

Are you on a price guide.


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## Marty S. (Oct 31, 2009)

Doc Holliday said:


> Led on left is one: legend which might be unlegible states led one (or two) solid board failure.


It says both on is board failure,left on and right off is pressure switch lock out. Reset the board and check the fan motor.


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## Doc Holliday (Mar 12, 2011)

Marty S. said:


> It says both on is board failure,left on and right off is pressure switch lock out. Reset the board and check the fan motor.


 
Great. I could've sworn it said one or two solid, board out. Poor guy, no a/c for two days cause I can't read..:whistling2:

BT, no price guide.


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## beenthere (Oct 11, 2008)

Best to stay away from their price guide contract.


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## Doc Holliday (Mar 12, 2011)

Marty, I picked up the replacement board this afternoon, installing it tomorrow. I'll admit that I did not put my gauges on the system as again, the legend states on the board "solid led one or two, board failure" but I do not know if there is any refrigerant in there. I'll check tomorrow and take pics. 

The new board should be going in tomorrow so I'll check refrigerant levels before I remove the board.

Thanks for the heads up on that.


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## Master of Cold (Aug 7, 2011)

There is a code for open pressure switch.


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## beenthere (Oct 11, 2008)

Even when you get a board failure code. You should run the system to see if anything else is wrong. This means bypassing the board to check contactor, RV, compressor, and condenser fan motor.


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## Marty S. (Oct 31, 2009)

There's no low pressure switch on a hp26 doc. The board has a space for one but they have a jumper in there. When that board gets 3 high pressure faults it locks the system out and gives a left light on and right light off code. That's why I said reset the board by removing R for a short time and then check the 65G60 fan motor. 

When reading two light diagnostic codes it's what 1 AND 2 are doing, not 1 or 2.


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## Doc Holliday (Mar 12, 2011)

Marty S. said:


> There's no low pressure switch on a hp26 doc. The board has a space for one but they have a jumper in there. When that board gets 3 high pressure faults it locks the system out and gives a left light on and right light off code. That's why I said reset the board by removing R for a short time and then check the 65G60 fan motor.
> 
> When reading two light diagnostic codes it's what 1 AND 2 are doing, not 1 or 2.


 
Marty, I can't begin to express how dim I feel yet how glad I am to have you on my side in this biz, thanks bud.

You were and are 110% correct. I went to the home today and took another GOOD look and sure enough "led one solid=high pressure switch lockout." 

DOH!

I checked continuity throught the switch and it was there. I noticed the low pressure switch absent and the jumper wires from one spade to the other on the board as you just stated it would be. I tried to start the unit as is (it had refrigerant in it but equalized without running at roughly 150 psig so it was slightly low just judging by equalized pressures.

So I replace the board and the replacement is not the exact same as the original, one green and one red led and they begin one on/off and the other on offset to the other slow flashing, the same signal as a hp lockout. So I remove the hp wires and jump the spades (like the lp which is non existant except for the spade jumper) and still nothing. I ask the homeowner before any of this if the stat is calling and he says "yes." 

After I switch the board with the home owner right there and still nothing he says, "Let me go and check the stat." 

He drops the stat into auto and COOL and bam, system runs. He had it in auto and OFF!!! _*ARRRRGGGGG!!!!*_

I have pics and I'll gladly post them tomorrow. I went with the board was bad regardless.

Thanks again, Marty!


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## Doc Holliday (Mar 12, 2011)

Marty, I took another pic as best I could of a close up of the original board. Here is that one and it is very blurry but the first line on top is where I made my mistake originally. It states "Led one" which would be the left side led solid meaning board failure or at least that's how I comprehended it the first time around.









Here's the replacement board. It was simultaneously flashing slow on and off which means normal operation at this time but the camera caught it with them both off for this one.









And I then caught them with them both on in this one.









The unit.









The one HP switch.


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## Doc Holliday (Mar 12, 2011)

And I cleaned not only that condesner but the smaller Lennox heat pump for the upstairs as well.









Thanks again, Marty.


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## Master of Cold (Aug 7, 2011)

Wow...you took the panels off to clean the coil..are you trying to get fired?


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## Doc Holliday (Mar 12, 2011)




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## JJboy (Oct 12, 2010)

LOL:thumbsup:


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## Marty S. (Oct 31, 2009)

No problem doc. This is heat pump country and I work for a long time lennox dealer. Figured you would either listen or give me the old fog horn leghorn "go away boy you bother me":laughing:


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## Final Notice (Aug 9, 2011)

i bet that condenser is cleaner right now than when it was new :two thumbs up:


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## JJboy (Oct 12, 2010)

In Texas everything is big :thumbsup:


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## Master of Cold (Aug 7, 2011)

I think florida is heat pump country.


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## Final Notice (Aug 9, 2011)

JJboy said:


> In Texas everything is big :thumbsup:


especially them speeding tickets


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## Doc Holliday (Mar 12, 2011)

Marty S. said:


> No problem doc. This is heat pump country and I work for a long time lennox dealer. Figured you would either listen or give me the old fog horn leghorn "go away boy you bother me":laughing:


 

Not at all, I look up to you guys. I like having you all with life times of experience around to help me, to straighten me out. Coming from a decade of only installing there's A LOT I do not know on the service side, but I'm learning. 

Thanks again.


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## Master of Cold (Aug 7, 2011)

I like installers. They keep me from having to do real work...


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