Heat Pump defrost cycle??
 

I have just a basic understanding of the refrigeration cycle of AC and Heat
pumps and once my unit is operating properly (I assume) I just take if for
granted.

During the cooler months of the year when I am using my heat pump, rather
than my pellet stove, I hear it occasionally go into a defrost cycle. The
fan in the outside unit will be stopped and I can hear the compressor
humming away. I've been told it is pump hot gas back into the outside coils
to eliminate any frost or condensation build up..

Now for my question: Several times a week I drive by a million dollar home
on the shore of Hood Canal. There is a AC/Heat Pump unit plainly visiable..
Well not exactly visiable during the winter since it is always totally
encased in gigantic ball of frost and ice. Really, it about 6 ft in
diameter. If I ever saw someone outside (and I thought I knew what I was
talking about) I would stop and suggest that they call the service man to
adjust the cycle control settings.

Tell me if I'm wrong, but I don't think a unit in this condition could be
operating anywhere near efficiently??

I know we have several AC people hanging out here.. Comments please??

Steve

Heat Pump defrost cycle??
 

"Steve" wrote in message
...
I have just a basic understanding of the refrigeration cycle of AC and
Heat
pumps and once my unit is operating properly (I assume) I just take if for
granted.

Hey..I am in the biz and I do too sometimes..LOL...
I got heat..what problem? LOL!


During the cooler months of the year when I am using my heat pump, rather
than my pellet stove, I hear it occasionally go into a defrost cycle. The
fan in the outside unit will be stopped and I can hear the compressor
humming away. I've been told it is pump hot gas back into the outside
coils
to eliminate any frost or condensation build up..

In a nutshell, correct. Reversing valve allows unit to go into cool mode,
bringing heat from inside the home to the coil outside, the fan stops so
that the heat build up is there without any interference from the air being
moved by the fan (altho, some units only drop 1 leg of the 220VAC to the fan
motor and it goes to roughly half speed) and you may get steam.

Now for my question: Several times a week I drive by a million dollar home
on the shore of Hood Canal. There is a AC/Heat Pump unit plainly
visiable..
Well not exactly visiable during the winter since it is always totally
encased in gigantic ball of frost and ice. Really, it about 6 ft in
diameter. If I ever saw someone outside (and I thought I knew what I was
talking about) I would stop and suggest that they call the service man to
adjust the cycle control settings.



Tell me if I'm wrong, but I don't think a unit in this condition could be
operating anywhere near efficiently??

Not_even_close.



I know we have several AC people hanging out here.. Comments please??

It probably has a defrost control failure, and as long as the secondary heat
is sized correctly, they probably have no idea. Depending on the model of
the snowball (:)) it might be a simple failure, or a bigger issue.
Personally, I think its great that you would even bother to do that, since
most would just ignore it..
The homeowners might think you are a nutcase, but who knows?


Steve

Heat Pump defrost cycle??
 

"Steve" wrote in message
...
I have just a basic understanding of the refrigeration cycle of AC and
Heat
pumps and once my unit is operating properly (I assume) I just take if for
granted.

During the cooler months of the year when I am using my heat pump, rather
than my pellet stove, I hear it occasionally go into a defrost cycle. The
fan in the outside unit will be stopped and I can hear the compressor
humming away. I've been told it is pump hot gas back into the outside
coils
to eliminate any frost or condensation build up..

Now for my question: Several times a week I drive by a million dollar home
on the shore of Hood Canal. There is a AC/Heat Pump unit plainly
visiable..
Well not exactly visiable during the winter since it is always totally
encased in gigantic ball of frost and ice. Really, it about 6 ft in
diameter. If I ever saw someone outside (and I thought I knew what I was
talking about) I would stop and suggest that they call the service man to
adjust the cycle control settings.

Frosting is also caused by being low or high on freon. It happens when
someone does not monitor the charging accurately.