Question for Res. HVAC experts

[moosehead]

Hello all. I have a question, and appreciate any guidance. My Mother in law called today and is having heating issues.
It's a 12 year old Rheem. Furnace and heat pump. Apparently the heat pump is having an issue, and the person she called out has told her the whole system needs to be replaced.

The control board is showing error code 27. My Google abilities tell me that this is low, or no voltage to the outside unit.

I am going to take over my multimeter tonight to check the supply, but is there anything in the unit I should be looking at otherwise?
Would a bad capacitor cause this type of problem?
I have had shut off 240 circuit breakers, and only had 1 side come back on, so at least I know what to look at there.

I'm just looking for simple things I can check out. Seems kind of odd to replace a whole system because of a voltage problem, but I suppose it is possible. We could fill many volumes with the things I don't know.

This is the first thing my Mother in law has had to deal with since we lost my Father in law. I just don't want her to get taken advantage of.

I will also accept names of solid HVAC people on the West side / Avon area.

Thank you.

 

[rhamersley]

Sounds like you're just going to have to check the disconnect on the outside of the house and make sure the disconnect part is pushed all the way into the base. Another thing that might be wrong is if the contactor has gone bad and isn't letting power through to the unit. Contactor is what the power wires hook up to in the unit and looks like this:

I have seen these lock in place and not make contact when the coil is energized. Might also check to make sure the control wires are still hooked to the contactor coil from the t-stat. Any real technicians chime in.

Good luck.

 

[Mr. Habib]

Measure the voltage drop across the contacts on the contactor. Should be close to 0. Possible for burned or pitted contacts to have high enough resistance to cause a problem.

 

[moosehead]

Thanks all. I’ve got new batteries in the meter. I’m really not understanding why they are telling her the system is done. Maybe it is a controller issue and they aren’t available?

 

[ChristianPatriot]

Thanks all. I’ve got new batteries in the meter. I’m really not understanding why they are telling her the system is done. Maybe it is a controller issue and they aren’t available?

It could be, because of the age of the unit, they don’t want to repair it and take the chance that something else goes wrong causing a “call back”.

Like others have said, if you’re comfortable doing so, check high voltage on the bottom of the contactor and check for 24v low voltage coming out of the transformer.

 

[JCSR]

Take a good look at the capacitor for bulging. Sure sign of a failure and an easy fix.

 

[rhamersley]

Take a good look at the capacitor for bulging. Sure sign of a failure and an easy fix.

I don't think a bulging capacitor would cause a no voltage fault...normally, it causes either the compressor, fan or both not to run, but it doesn't stop voltage from reaching the control board unit (mis "spoke").

 

[CHCRandy]

Hello all. I have a question, and appreciate any guidance. My Mother in law called today and is having heating issues.
It's a 12 year old Rheem. Furnace and heat pump. Apparently the heat pump is having an issue, and the person she called out has told her the whole system needs to be replaced.

The control board is showing error code 27. My Google abilities tell me that this is low, or no voltage to the outside unit.

I am going to take over my multimeter tonight to check the supply, but is there anything in the unit I should be looking at otherwise?
Would a bad capacitor cause this type of problem?
I have had shut off 240 circuit breakers, and only had 1 side come back on, so at least I know what to look at there.

I'm just looking for simple things I can check out. Seems kind of odd to replace a whole system because of a voltage problem, but I suppose it is possible. We could fill many volumes with the things I don't know.

This is the first thing my Mother in law has had to deal with since we lost my Father in law. I just don't want her to get taken advantage of.

I will also accept names of solid HVAC people on the West side / Avon area.

Thank you.

Call Frank Polley (317) 997-8317 Tell him Randy Beavers gave you his number.......you will not find a more honest man.

 

[Lpherr]

I hope you're able to repair it. Our furnace decided to crap out in Nov. and the tech tried the usual thermal couple and transformer.
I explained this happened before, and I changed the gas valve. Didn't have another problem for 18 years, until it wouldn't stay lit this time. He said he could change the valve for $517, but wouldn't guarantee it to work. The unit was built in '88, so we opted for new. Being cold and no heat, we didn't have time to shop around. Stock was limited, and we chose an upper end unit that was available, and after talking with other people that had recently had installs, I don't think we were bent over too far. We've been happy with it so far.

 

[JCSR]

I don't think a bulging capacitor would cause a no voltage fault...normally, it causes either the compressor, fan or both not to run, but it doesn't stop voltage from reaching the control board unit (mis "spoke").

That is true. But dealing with electrical circuits very few problems are "normal".

 

[Cameramonkey]

That is true. But dealing with electrical circuits very few problems are "normal".

Like my mom's furnace. It kept throwing weird motherboard related errors. But they were vague and the contractor didnt want to replace the board under warranty. And it was intermittent. It would run for a day or two then error. Then after a reset, the same. EDIT: I forgot they replaced the board ONCE. But the problem persisted.

Luckily the THIRD teach was a grizzled vet. He went to the breaker panel, and sure enough the Neutral wire was loose. He was able to put an additional 1/4 turn on the screw. that looseness was enough to introduce noise into the line, freaking out the board. Its been running clean for 3 years now.

 

[JCSR]

Like my mom's furnace. It kept throwing weird motherboard related errors. But they were vague and the contractor didnt want to replace the board under warranty. And it was intermittent. It would run for a day or two then error. Then after a reset, the same. EDIT: I forgot they replaced the board ONCE. But the problem persisted.

Luckily the THIRD teach was a grizzled vet. He went to the breaker panel, and sure enough the Neutral wire was loose. He was able to put an additional 1/4 turn on the screw. that looseness was enough to introduce noise into the line, freaking out the board. Its been running clean for 3 years now.

Old guys (like me) always start at the source and work your way to the trouble.

 

[churchmouse]

Thanks all. I’ve got new batteries in the meter. I’m really not understanding why they are telling her the system is done. Maybe it is a controller issue and they aren’t available?

That is a standard now with commission service techs. They have to generate as much work (real or imaginary) to get top pay and commission. It is the new way In The rape the customer residential service company’s.

Line voltage is a completely separate path than low voltage. Bulged caps and stuck contacts are as well.

Oh, and I totally hate Rheem equipment. Used them for 1 season and way to much trouble.
Is the error code on the outdoor unit or in the air handler board..??

 

[churchmouse]

Old guys (like me) always start at the source and work your way to the trouble.

It is a solid path.

 

[churchmouse]

Like my mom's furnace. It kept throwing weird motherboard related errors. But they were vague and the contractor didnt want to replace the board under warranty. And it was intermittent. It would run for a day or two then error. Then after a reset, the same. EDIT: I forgot they replaced the board ONCE. But the problem persisted.

Luckily the THIRD teach was a grizzled vet. He went to the breaker panel, and sure enough the Neutral wire was loose. He was able to put an additional 1/4 turn on the screw. that looseness was enough to introduce noise into the line, freaking out the board. Its been running clean for 3 years now.

This is why I have a high end true RMS meter to check this.

 

[moosehead]

That is a standard now with commission service techs. They have to generate as much work (real or imaginary) to get top pay and commission. It is the new way In The rape the customer residential service company’s.

Line voltage is a completely separate path than low voltage. Bulged caps and stuck contacts are as well.

Oh, and I totally hate Rheem equipment. Used them for 1 season and way to much trouble.
Is the error code on the outdoor unit or in the air handler board..??

Outside error codes 23 and 27. I’ve found 27 is power. No info on 23. Thank you sir.

I appreciate the advice and references. I’m going through the power side tonight. Anything else is above my pay abilities.

 

[churchmouse]

Outside error codes 23 and 27. I’ve found 27 is power. No info on 23. Thank you sir.

I appreciate the advice and references. I’m going through the power side tonight. Anything else is above my pay abilities.

You have my number. Call me if you have a question. I would as soon see you fix something small as have to R&R the entire system.

 

[BiscuitsandGravy]

Speaking of LP fired furnaces and AC units... And not to thread jack... What are some decent brands for a DIY replacement for a next summer time frame? Our current unit is 17+ years old and on its way out. Trying to limp it through the winter...

 

[ChristianPatriot]

Speaking of LP fired furnaces and AC units... And not to thread jack... What are some decent brands for a DIY replacement for a next summer time frame? Our current unit is 17+ years old and on its way out. Trying to limp it through the winter...

If you don’t have the HVAC specific tools (gauges, vacuum pump, refrigerant), then DIY is a no go.

 

[KG1]

If you don’t have the HVAC specific tools (gauges, vacuum pump, refrigerant), then DIY is a no go.

This. Improper installation could lead to big problems down the road.