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heathstone heritage

New Member
Jan 1, 2018
Storrs, CT
Hi All!
Happy New Year! It's cold in CT!

Daikin heat pump system installed in this 1, 253 sq ft two floor ranch house last March. 36,000BTU, 17.7 SEER. Two units with multi-heads (3/4) to cover seven rooms.

Now it's being tested. Says it is efficient down to 5 degrees. It is 3 degrees now, heading to 1 (!!) There's a number of nights coming up where the temps will be below 5 and two extreme -9 and - 11 predicted. That's not wind chill. I'm trying to figure out the plan for what's coming.

I've got a Hearthstone Phoenix woodstove in the living room with drafty cathedral ceiling (ouch.)
It sits right in the center of the main living room wall with the wall going up behind it to the ceiling that matches the width of the chimney outside. There are big, cool but totally non-energy efficient windows on either side of this middle width that run the top of the wall on each side (3 ft tall by 12ft wide)

The installers of the Daikin unit put the minisplit indoor unit in the livingroom just above the wood stove about 4 1/2 feet slightly to the left (about half the Daikin is directly above left half of the wood stove.)

First of all, is that ok??? I assume they wouldn't have put it there is there were safety issues.

Second of all, do I leave mini-split on while using wood stove? I assume there's no problem with that.
Do I change temperature setting? or just do as usual and get a fire going?

Third of all, what happens to heat pump below 5 degrees? I'm going to find out tonight first hand -- does it stop altogether? Keep trying to produce heat? Produce less heat? Do I leave it on no matter how cold it gets?

Tonight is sort of a warm-up for the coming minus degree predictions ahead which are extreme and rare for this area. Windchill will be -30 on those two nights.

Appreciate your help, if you know the answers.


Minister of Fire
Jul 11, 2008
Northern NH
I dont have a daiken but do have a Mitsubishi cold climate heat pump. Yes it puts out heat down to below zero but its sure not hot, its warmer than the room air but that is about it. If its cold and dry it will go into defrost cycle on occasion but if there is any precip in the air it will go into defrost so frequently its annoying. The COP drops with the temperature, at some point its not really that efficient. I turn mine off when the night time temps drop under 10 F even though its rated to run down to -12 F. If you do run it in low temps, set it and forget it, leave it one temp 24/7.
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