Odd noise from heat pump

MrHurt

Hi,



I am having a problem with the ouside heat pump.  I have an all electric system.

The outside unit is making these very loud screaching noises.  It seems to happen during the day and night, but not always.  I have called out a technician twice, and the noise did not occur when they were here (terrible luck).  But the noise is so loud, that it wakes us up at night.  As we have a toddler, it takes a long time to get the baby back to sleep.  The last 2 nights it has occurred around 3 am.  But the noise is just as likely to happen during the daytime.  It is so loud that you can hear it out in the street.



The first tech asked me to record it, and he would be abe to diagnose it.  So I recorded some of it today at 1pm, and a tech was back at the house at 2:30pm.  Unfortunately, the tech was unable to make anything from the recording (different from the first tech).  And since the noise did not occur while he was here, nothing was done.



I recorded the sound on an iphone, so it is not great, but you can hear it.  I will attach the file.  In person, it is so loud that it will vibrate you ou of the bed. 



I am hoping that someone here might have experience with this, as we are having a hard time sleeping at night (and so is the baby).



*** It will not let me attach the sound file.  It is a small file, and I would be happy to email it to someone.

Michael

nicholas bonham-carter

Strange noise

While it is running, push on all the panels to see if that would cause the fan to rub against its housing. Perhaps an animal has jumped up on top of it, and caused the cabinet to deform slightly.--NBC

MrHurt

Tried the 4 sides

Hi Nicholas,



I turned it on and pushed from all sides, but that did not make any noise.  There seems to be plenty of clearance.



The noise is not the normal screeching associated with the motor about to go bad.  It is a loud RHHHHHHRRRRROMp, 1 sec pause, RHHHHHHRRRRROMp, pause, RHHHHHHRRRRROMp......... for about 3 min.



And it is really loud.  I would be happy to send the small recording I made from this afternoon.  It reminds me of the noise made by the alien tri-legged ships in the War of the Worlds movie.  And it will certainly wake you up in the middle of the night.



Michael

alotlikeearl

Something to check

Did the tech force the unit into a defrost cycle?  Could be a problem with the reversing valve during defrost.

Good luck!

MrHurt

Defrost cycle

Thanks for the reply.



The tech did do a defrost cycle.  Would the reversing valve be activated during the day also? 

alotlikeearl

Defrost

Yes; unit will defrost as needed day or night.

What brand is the heat pump?

Steve Whitbeck

reversing valve

The reversing valve is acting up. either the solenoid is going bad or it isn't getting proper voltage. sounds to me that the valve is not staying in full open when energized.

MrHurt

re

@ Alot:  The 2 units are Goodman.  They were both installed at the end of 2008.  Every year the capacitors go out, and one of the fan motors has been replaced.



@ Steve:  Thank you.  I will call out the tech again Monday and mention the reversing valve (well, basically, just repeat what you wrote there). 



The noise is ridiculously loud and wakes us up. 



Michael

Steve Whitbeck

valve

If the heat pump is under full operating pressure and the reversing vavle switches modes it will make a lot of noise. I do a freeze thaw process on geothermal heat pumps to clean the water heat exchanger where I reverse it under full pressure - Makes a LOT of noise.

VictoriaEnergy

heater

I'm thinking since the problem often happens in the middle of the night, so maybe when the unit has been off for a long time due to tstat setback, the unit is very cold....that's a hint.



The 1st thing I'd be having a look at is the crankcase heater. and the relay on the bioard powering it.

unclejohn

Is it very cold

Where you are? The defost cycle should not be longer then 10 minutes. If you are in a warmer area the unit will go into defrost almost every 90 minutes but should only last a few minutes. If it does not come out of defrost the defrost stat may be bad causing the compressor to run super high head pressure and make a lot of noise.