Heat Pumps and Electric Heating - Odd sound from heat pump.....

I have narrowed down an odd noise to the heat pump. I have eliminated the ducts, blower fan, etc. The noise only appears when the heat pump is in heating stage 1. The noise does not become as apparent in heating stage 2. There is no noise when the heat pump is in cooling mode, at all.

The noise is like a higher pitched whine or whistling. It sounds a lot like hot water pipes/flow at times. I think it is coming from the copper refrigerant lines.

This is a new system. Is this a normal sound? Is there any way to deaden this sound? It is not overly loud but a very annoying sound that keeps me up at night.

I would guess that what you are hearing is blowing air going through the duct work at high speed.Is your blower motor a single speed or multiple speed? Mine switches automatically to high speed for heating mode.

You could be getting some kind of vibration when the compressor runs at that lower speed. The vibration could be travelling up the refrigerant lines.

Stethoscopes are great for pinning down problems like this.

It is not the blower. The blower maintains speed for a while after the heat kicks off and the sound immediately stops when the heat pump stops. I have tracked it down to 100% certain it is the copper refrigerant lines.

I'm not sure the noise is from the vibrations of the compressor or not. After some reading, I think it is just the sound of the refrigerant. I guess there is a valve that allows a different rate of flow during heating cycles vs. cooling cycles.

If it is vibrations from the compressor, what can be done?

It could be something simple like a shock mount on the compressor that's worn or the compressor wasn't properly secured, a cooper line that's not isolated. Holding onto the line in the trouble area might dampen it confirming where it is vibrating.

It is possible you have a bad compressor, TX valve or are low on charge. Any of these will affect performance so it may pay for itself to have these checked out. If you can localize the problem it should reduced the cost of the service call.

It was just installed in July. It is 100% parts and labor warranty for two years. I'll be having them look at it when they come for the fall maintenance visit.

It sounds more like it is just the sound of the refrigerant flowing through the lines itself. Not really a vibration.

It was just installed in July. It is 100% parts and labor warranty for two years. I'll be having them look at it when they come for the fall maintenance visit.

It sounds more like it is just the sound of the refrigerant flowing through the lines itself. Not really a vibration.

Have them write down the pressures, all temperatures including superheat and subcool values and temperature rise (delta t). Then re-post here and at hvac-talk to double check you have the right charge. HVAC techs have been known to know follow the correct procedures for charging.

about how many pressures are there, just 2?

any other temps besides delta-t, superheat, subcool?

So apparently this is normal for the newer R410-a systems since they run at much higher pressures. I knew it was coming from the refrigerant flow but I was hoping it was fixable.

One thing to check is if the liquid line is vibrating when the compressor is on. I had the same problem on my new HP and realized the copper tubing was rubbing against the metal casing and making alot of noise. I fixed it by wrapping a plastic lock strap around it and the suction line so that snugged them up.

I doubt that the manufacturer designed it to make noise in the heat mode. I would say that you have a refrigerant level problem. What Brand Model and Size unit have you got there?

The noise has actually died by about 90% since the tech came out and took just a bit out. So I can't really complain anymore.

I doubt that the manufacturer designed it to make noise in the heat mode. I would say that you have a refrigerant level problem. What Brand Model and Size unit have you got there?

It is a 3 ton Amana ASZ16, 4-ton coil w/ TXV, Amana AMV8 80k BTU. It is not actually a noise from the equipment. It is, or was, the sound of the refrigerant flowing through the copper lines. It sounds exactly like hot water flowing through pipes in a boiler system, just not as loud.

But, now that it is pretty much gone, all I hear is the outside condensing unit. Do you know if they make a vibration isolation kit for the copper lines like Lennox does?

Here are the notes from the service call:

Manifold Gas Pressure = 4.3
Temp rise = 54
Supply air 124
return air 69

Heat Pump pressures
low side 125
high side 353