Mitsubishi v PURY 250 YMF-B R22 WARM UP MODE ?

[Paultighe]

Can anyone tell me what determines the warm up mode before the compressor starts ? Is it....
1.TH6 below 10 or 5 degs C
2.Is the inverter board monitoring the compressor windings ?

[Thermatech]

I seem to remember warm up mode if TH6 lower than +5 deg C

This is a safety function to ensure no liquid refrigerant in compressor shell before start up.
After 2 hrs this fuction should time out & the comp should start.


You will also notice that the unit will deploy warm up mode if the start up amps is high & the unit stops on preliminary overcurrent
then
the unit will use warm up for about 5 mins & try for another restart.
If it fails on preliminary overcurrent 3 times
then
At the 4th start the unit will stop on 4210 overcurrent.

Again the warm up is to ensure no liquid refrigerant is in compressor shell which could cause overcurrent at start up.

[Paultighe]

Thanks it was a new compressor that was installed and on the first day on start up we had alot of 4210 faults and warm up modes. Looks like it has settled now.