Low temperature a/c questions.

[airedog]

Anyone here running Mitsubishisi M series through winter temps below -20F on occasion? Do the units shut down or is there diminished cooling? Currently the difference in price M to P series puts it way outside my personal use medical budget.

 

[1989cheeseSOG]

-30 degree C? it's very cold, do you have the notice ? i think they usually advice aroud -15celsius minimum in cold mode

 

[airedog]

There advertised as being capable of -40 up here in Canada; that may be with an added kit though. Quotes are a tad high for this small personal use med grower though, maybe another year.

 

[1989cheeseSOG]

are you sure you even need cooling with temp that cold outside ? heating yes, dehumidification too, but if your room is large with high ceilings maybe natural cooling through the walls would be enough
idk
in winter i don't need any cooling for my veg rooms, and i got co2 buner in it, actually the split in it run in heat mode to keep 27-28 degree in the room
and winters here are far from being so cold as yours

 

[Grapefruitroop]

Currently the difference in price M to P series puts it way outside my personal use medical budget.

Yup thers big difference in price but i can guarantee you that every single cent more is worth and is gona pay by itself by saving A LOT of power and giving you a very reliable machine.
If you can try to make an effort and save for the top notch unit..do it...it will not disappoint you, it will use almost no power!!!
Sorry i cant answer to your question but the manual can.
If you go check the tecnical specs in the manual online, you will find it clearly specified the operating temps of the outdoor unit.
Plus checking the power consumption and the SEER/ SCOOP values will help you to make a decision....

 

[airedog]

As a vented room, i was hitting up to 87 degrees during flower and low 70s during lights off, due to dehueys, chiller, pumps, etc.. Basement room, 7' of headroom.