I'm not a tech, I'm a homeowner. We purchased an apartment in NYC and one of the conditions on closing was that the building install 4 new PTAC units that were thermostatically controlled (vs. the PTAC units that were already installed that just have on/off, hi/lo, hot/cold)
The units they chose were McQuay R-410A MHC Standard Range & MHW Geothermal. We've had nothing but a string of problems. One unit was pulled immediately to have the compressor replaced. Another one had a drain issue that caused water damage on the floor. A third would randomly blow heat during the summer and now doesn't turn on at all (they've ordered a new thermostat/receiver and expect it in 4-5 weeks).
My question though is with the 3 units that do turn on. Please someone tell me if this is normal. Here's what happens.
Come in to cold apartment (low 60s).
Set thermostat to 70.
Fan comes on.
Compressor comes on blowing warm air.
Room heats to set point of 70.
Unit turns off.
Wait for temperature on thermostat to drop below set point
Fan on unit comes on
Compressor comes on blowing COLD air
temperature continues to drop
Once temperature has dropped 2-3 degrees the compressor goes off
Fan stays on
Compressor comes back on blowing warm air
This doesn't seem normal, but every time someone tests it, they just turn the temperature up 4 degrees, the heat comes on and they claim it works. They are coming back on Thursday and I'm hoping I can have them stick around to see the problem.
Thank you for any advice you can provide.