I know it is late in the cold season, but I swear I have hardly had any
heat pump calls until these past three weeks. Now pretty much every
call is a heat pump. It is causing me great stress.
I have been reading a bunch of heat pump threads and trying to gleen info,
but I'm almost out of weekend time for this weekend--I have other tasks
I need to do today.
So my questions are about putting gauges on a heat pump in
heat pump mode. I don't because I have absolutely no clue
what they would tell me. Even in low ambient, I put in a/c mode
and then will maybe check SH/SC if pressures aren't really obvious.
I have come across the two semi-accepted heat pump charge checking
#1 Hot gas: Adding 110 to your outdoor air and checking that against the discharge line temp.
I am guessing that lower means too little refrigerant, higher is overcharged.
#2 Un-named: (Ambient DB +20) times .4=temp rise indoors (at air-handler?)
I'm assuming that lower rise means undercharged, and higher rise means run back
to your van. Ha, ha.
But then I see this third schraeder valve on a lot of heat pumps and I have to
believe that it is meant to be used. I believe it is tied to the inlet of the compressor
close to the reversing valve? (I have not actually checked that on a unit, just gathered
it from my reading.)
So my question is simply whether I should actually put on gauges in heat
mode, whether I should ALWAYS use that third port, and what can pressures/sat temps
Thank you all.