"William Stacy" wrote in message
. net...


PrecisionMachinisT wrote:

So most units will have controls hardware installed that forces them into
into a reverse cycle mode in order that mass airflow capacity through the
outside coils can be regained--the outdoor fan will stop, yet the
compressor
and indoors unit still runs....most notably, very cold air will be
typoically be felt coming from the inside supply registers if there is no
active backup heat during defrost.


I've seen that. The indoor fan is blowing cold, the outside fan is off,
the compressor is running, and there's a coating of ice all over the
fins. I'm curious as to why it's not programmed to stop the indoor fan
from running while this defrost cycle is working. Seems to make no
sense.

During defrost, the unit is essentially running as an air conditioner--the
indoors fan needs to be running so that some heat can be picked up from the
inside air--this heat is then rejected to the outside for the purpose of
melting the ice formation.

IF the the indoors fan wasn't running, then insuffient heat supply would
likely cause the indoors coil to also quickly freeze up....leading to
possible compressor damage due to floodback.


Anyway, I appreciate all the input, even if it boors some of you
guys. I know I'm getting better info here than I'd get on
alt.home.repair. We get the same thing over on sci.med.vision, where I'm
a regular contributor. I have learned to skip the obvious and the
annoying, and to not waste time on the idiotic. Sorry if I missed a faq
that would have solved my problem.

Anyhow, I've got lots of ammo for when the boss from the install company
comes by. It makes sense that the heater board or whatever defrosts it
is out. BTW the serial # someone asked for is: (S) NKNM119678 if that's
of any consequense.


--

SVL