I have never seen a heat pump that did not kick on aux. heat during defrost, but that's not to say there aren't any. Did you check the circuit breaker for the aux. heat, if it's on a separate breaker?

Your backup heat most certainly does kick in during a defrost cycle! In defrost a heat pump reverts back to the air conditioning mode but with the outdoor fan off. This directs the hot refrigerant gas to the outdoor coil and melts the ice. All heat pump systems have a defrost relay, or several, and that relay usually has a considerable number of terminals in it because a heat pump has to do several things in order to execute a defrost cycle. They could be a nightmare to troubleshoot some time but thats part of the fun of the trade. (NOT) Tell your service/installer guy to read up on how a heat pump is supposed to work then come down and do something about the cold air coming out of your registers when it's not supposed to!

Actually aux heat kicking on during defrost is (most of the time according to what brand unit) a option for the installer to hook up at the time of installation. Typically there is a wire off the defrost board itself that runs back to the electric aux heat coils to activate the relay. To troubleshoot your system the very first thing that I would do would be to set the t-stat to emergency heat and verify that the electric aux heat coils are EVEN working. You may just have a tripped breaker. Check that and post back what you have. Note: the heat coils will have separate breakers from the heat pump condenser and furnace so check that out.

I know the breaker is on because the aux heat will come on. In fact when it does a defrost sometimes the house will drop 3 degrees below where it should be and then when the defrost is over the aux heat kicks in to heat the house up quicker cause on the thermostat that symbol is blinking that mean aux heat. Then after the temp gets right it clicks and the sign stops blinking and it is just heat pump then or it has cut off most time. Then when it runs a while the next time it comes on it does this all over again. I have never noticed it getting this cool in here before. Does the vari-speed blower get faster during this time cause the aux heat is on(or supposed to be?) cause when it is doing this it is blowing like crazy!! That is why the temp drops so fast I guess.

sparky I suspect that you have a staged aux heat coils and the one side that is aux heat (2) and wired for defrost is burned out or has a bad relay. What unit are we working with here and what t-stat? Do you have a clamp on amp probe? the name sparky seems to indicate a tool box full of fancy electrical meters and probes have you gotem? Post the unit and t-stat info so we can fix you.

Well to begin with I have a Goodman unit(I know the cussing will start there) but I had an Amana for 18 years and only spent $35 on it the whole time. When I decided to get the new one the same installer did it (minus the Dad he has passed away) and he said the Goodman are the same as Amana. I have read that the install is the key not the brand name. I have been told by several people that I have the quietest one they have ever seen but I think it is the ductwork(the Dad laid all that out.I also liked the warranty this unit has--lifetime for compressor cause hopefully I will be staying in this house--nursing home next(HA). I have been well pleased with it till now and it is OK now except for that cold wind during the defrost. No I have none of the tools you are talking about so the name is misleading. The thermostat is a White Rodgers digital. Are they a piece of junk? I think that something is not kicking on or in when it is supposed to. Do you not love the way techs tell you that your (whatever) is not doing like it is doing when you tell them it is. I have had this at car dealers also which most time they (car) won't do it till you start home then you don't know if you are going to get there or not but when the service guy is driving it, it is slick as glass!! Just life I guess. Any ideas would be helpful..

Sparky:

The only people that bad-mouth the new Goodmans are ignorant. Pay them no mind.

I installed a GSH14 heat pump in June and so far it has been outstanding.

I have 15kw auxillary electric strips and all 15kw energizes during defrost. The heat kit that came with the unit, HKR-15C, simple plugged directly into a matching plug into the ARUF air handler.

My guess is you have a loose wire. Your tech should be able to force a defrost cycle and find the problem. I don't think you have a problem with your thermostat.

FYI - I believe that your outside unit has time-initiated defrost, meaning that you can select between 30-60-90 minutes start time (after the unit has run for "x" minutes when the coil temp is less than 32 degrees, it will defrost). There is an electronic pin under the access plate that you can re-position to change the setting. I moved the setting from the factory set 60 minutes to the max of 90 minutes as I was having no problems with icing up.

Best to you.

I talked to the owner today and he said that yes the aux should be on for defrost. He said it was a bad board not letting it kick in and that he would get the board and be out to repair it. That will probably be Monday but right now it isnt that cold so that is ok. Seems like everything we get now has control boards be it the heat pumps, washers,refrigerators, etc. In fact I have got to buy a new fridge(comp out on mine) and I have no idea what to buy anymore. Any reason this board would be out in 2 years??

A board on my Carrier (2.5 years old at the time) went bad summer of 2006, causing one heating element to energize whenever the blower & A/C *weren't* running (it still cooled perfectly fine), constantly kicking-out on the overheat 'stat due to no airflow. I noticed a higher-than-usual bill for a couple months, raised the setback temp by a degree or two, which in-effect made it worse, LOL. The repair tech made a remark to the effect that it's a known problem with flaky boards on the particular model ... which sucks for me.

"Any reason this board would be out in 2 years??"
- It's just the luck of the draw that you got a bad circuit board. That part should be covered under warranty but not the labor.

This is one of the reasons I stuck with a fixed speed motor in the air handler - simpler, less sophisticated circuitry. Cheaper to replace if it should fail out of warranty.

Service guy came back last week with the new board and replaced it in the heat pump part of the unit. He said try that and let him know. It was no different than it has been. I called and told him and he said then it was the board in the air handler so he came today to change that. He made it go into defrost first and checked the amps and he said that the Aux heat was kicking in on the defrost and that there was no use to change the board in the air handler since it was reading right. He said that maybe I just hadn't noticed it before untill lately(being cooler). He said that the air would drop to about 78 degrees during the defrost with the Aux heat on. I just can't believe that it has done this for the past 2 years and I didn't notice till now. The house gets noticeably cooler in that time like from 72 to 69. I know it is only 3 degrees but when the blower is on HI(and it is during this time) it cools down fast. Anything else I should have him check?? He did say he was going to call someone with the comapny and ask them about this and see if they could tell him something that he has "missed".

Any Ideas??

Dadoes--But if it put out enough heat in the beggining it should still be doing so-right?

At least it has warmed up here so I am not using much heat. Now dealing with Tornadoes.

Sparky:

1. What is the kilowatt rating on your back-up electric strips, 10 kw? 15 kw?. They come 5 kw each - 2 are 10 kw, 3 are 15 kw.

2. Did the tech check and make sure that all of the strips are being energized when in defrost?

3. Did you check if the condenser is set at 30, 60, or 90 minutes of defrost time? 90 minutes will defrost less frequently.

Not sure but I think it is 10 kw on the strips.

He didn't check the strips--just made it defrost and said it was kicking in according to the amps.

The defrost is on 60 min. I need to change this to 90??

If the 10k heat was fine at the start why would it not be now? Nothing has changed inside. I still dont think it is kicking on because after the defrost shuts off then the aux heat symbol on the thermostat starts blinking and the air is warm then. I will have to check for sure about the heat strips but I think it is 10kw instead of 15.

"He didn't check the strips--just made it defrost and said it was kicking in according to the amps."

- The 10 kw strips consist of two 5 kw sections. Only one 5kw section may be operating properly. Bad wire or bad sequencer. Get his a$$ back and have him meter the strips while the condenser is in defrost to make sure that all strips are energized. If you have 10kw strips and both are working fine, replace them with 15 kw strips (Goodman part# HKR-15C, approx $100). Did he check the air temperature after the strips to see if you were getting the 76 degrees that he stated?

"The defrost is on 60 min. I need to change this to 90??"
- Depending on climate and conditions, a longer defrost initiation time saves you money and helps with wear-n-tear on your system. I moved mine from 60 to 90 minutes with no problems with freeze-up, in Baltimore.

FYI
10 kw electric strips provide an approximate 26 degree temperature rise at 1200 CFM fan speedd. If the air temp before the coil is 50 degrees, then the air temp after the coil is 50 + 26 = 76 degrees.

If one of the 5 kw strips is not working, then 5 kw provides only a 13 degree rise, so 50 + 13 is 63 degrees. This will cool the house.

15kw strips provide a 40 degree rise in temperature.

Good luck.

He didnt check the strips or the air temp--just said that it would be about 78 (might have said 76) degrees. I just know that it hasn't been this way till January.

He changed the defrost time from 30 to 60 when he was here to put in the board so mine has run on 30 min for 2 years. I live in north central Alabama so I am sure that 90 would do fine.? My air handler,strip heat and all that is in the attic if this matters??

If I went to 15kw heat would he just add a 5kw heat strip to the ones I have or do they come made like rated for 15 in one strip? I was thinking for 15 I would have 3-5kw strips?? I feel like one of mine is out and this is why it is cold on defrost cause when the defrost is over it goes to aux heat and it heats up then but this could still just be using the one strip-right-but it seems pretty warm on that. It is really like the heat just doesn't kick in on the defrost part at all but he says according to the amp reading it is on. I know the meter gets lots faster during this time but in Jan my power bill went from $200 a month to $323 and it wasn't much colder thanit had been being, then Feb bill was $267 but it was a shorter month and it was a bit warmer.

15 kw heat strips may be too much. you dont want your heat strips to be to big because if they are too big when it goes in to defrost it will heat the house too fast and not let the system finish its defrosting then you will have a big problem. i set all units on 30 minutes. if it is set on 30 minutes it doesnt mean it is going to go into defrost every 30 minutes it is only going to go in to defrost when the coil tempature is cold enough. if it is set for too long then it will freeze up and the system will not be able to defrost it itself. they need to check the strips with an ammeter at the indoor unit that is the only way to tell if the strips is turning on.

Sparky
New to the forum. Having similar problem re defrost cycle.
Cold air was comming in while on defrost. Tech came yesterday fixed it so the furnace would go on during the defrost cycle. Worked ok during the day, was woken up at 2 and at 4 by this house shaking noise that lasted about 10 seconds. I am guessing this happened during the time the furnace was going on while the heat pump was on defrost.

Did you ever find a solution to your problem?
Please let me know.
Thanks

sounds like it could be a lose wire. or a bad defrost "relay".