Heat Pump "Noise"

[JamesRW]

Does this "sound" right? Had a Lennox CBX27-UH-036/20KW (Electric) furnace and a XP14-030 2 1/2 ton AC/Heat Pump installed in August 2009. Seemed to run ok until the first night temp fell below freezing. Woke up to NO HEAT! Unit had not been wired to the thermostat correctly! A senior technician came out and re-wired it. After that we noticed that each time the heat pump would kick in, there was a seemingly loud "clunk".....called the installer and the same senior tech came out and added a "booster" unit. He said they are usually needed in colder climates (well, crap, this is North Dakota) so why wasn't it done at installation? Anyway, we also questioned how often it was cycling and the initial installers had set it for the max - 9 times per hour! He then reset it for 3 times per hour. We're still hearing the noise on startup, though it isn't as loud. Is this a problem? (Have also had a terrible time getting this company to register our extended warranty - tomorrow is the 90 day deadline, or get the tax rebate information certification papers to us.) Just want to clear all this up before 20 below! Thanks for any help!

[beenthere]

Without knowing what noise its making. We can't tell you how serious it is or isn't.

Some people make a recording of the noise. And put it on utube and post a link. So we can hear it. Might want to consider doing that.

[JamesRW]

In your expert opinion, could you tell me what is "normal"? I've read that "heat pump compressors have a soft start system that reduces the input current until they get going." It did NOT make this sound during the air conditioning season.

[CE-TECH]

Too me sounds like the compressor has a bit of liquid in the crankcase on startup. But Can't garauntee without hearing the noise. (just like beenthere said) I wondering if the 'booster kit' is a crankcase heater or what he put on. This wouldn't do this in the summer because the compressor stayed hot enough that refrigerant didn't condense in the compressor

[beenthere]

You were slightly mislead about heat pump compressors.

They may have been refering to Copeland scroll compressors start unloaded.
But, they do that weather they are in a heat pump or A/C only unit.

I believe you have an installer created issue.

[JamesRW]

"Precision-engineered scroll compressor with special compressor sound dampening system assures smooth, quiet operation."

What is Lennox referring to? (This is in the Elite Series brochure).

[beenthere]

Probably a sound blanket over the compressor.

They use the same scroll compressors that pretty much everybody else uses.

[seanddd]

wrong post, deleted.

[pacnw]

what about the reversing valve making the noise?

is it energized in cooling or heating for Lennox?

[platchford]

Too me sounds like the compressor has a bit of liquid in the crankcase on startup. But Can't garauntee without hearing the noise. (just like beenthere said) I wondering if the 'booster kit' is a crankcase heater or what he put on. This wouldn't do this in the summer because the compressor stayed hot enough that refrigerant didn't condense in the compressor

The first thing I thought of when he said booster kit was a hard start kit (capacitor) rather than a crankcase heater... but who knows... you'll have to ask the tech specifically what he added.

Regarding the crankcase heater, you bring up a good point. I don't recall whether those models come factory-equipped with one or not. If not, it certainly would be a good idea to add one in North Dakota.



what about the reversing valve making the noise?

is it energized in cooling or heating for Lennox?

Lennox is energized in cooling like most manufacturers.

[tompoynor]

I don't know it was a good idea to put a heat pump north of Oklahoma.

[EdC]

It has been my understanding that Copeland scrolls in residential service
have no need for CCH.

[platchford]

It has been my understanding that Copeland scrolls in residential service
have no need for CCH.

From the perspective of not having to worry about them slugging liquid and not causing damage, you are correct. However, I would still wonder if the noise could be related.

[seanddd]

Please come back tell us what the diagnosis and fix are.