Daikin Mini-split struggling in NH

nevinnh

I'm in southern NH. Temps have been from 25-40 last couple days.

Space has 3 rooms, each with an indoor unit: 2@ 7K BTU, 1@ 18K BTU.

Two days ago I shut off the 18K unit overnight to air out the room. Next day it could not get the space much above 62. Periodically, it's blowing semi-warm air. I'm not sure if shutting it off overnight has anything to do with this, or its just a coincidence.

The smaller units seem to be running fine.

I've stopped and started each indoor unit and power-cycled the outdoor unit.

I checked the remote for a troubleshooting code and each indicated F03 until I restarted the outdoor unit. Now, none of the 3 remotes indicates a code.

Any thoughts?

ethicalpaul

Check the manual for the meaning of the code. On mine, I get a code if any of the head units are set to "cool" when any other is set to "heat". It might be as simple as that.

Based on what you saw, I wouldn't try a setback again until spring

Did you "air out" the room with outdoor freezing cold air? For how long? How low did the temp get in that room?

pecmsg

Heat pumps do not like set backs. 

Your sizes are close to what’s in our summer house. Cooling is pretty good, heating is only to take the chill off! 

How were these sized?

Robert_25

If you let the room go cold it might take nearly an entire day to get heated back up if it is below freezing outdoors.

Jamie Hall

Robert_25 said:

If you let the room go cold it might take nearly an entire day to get heated back up if it is below freezing outdoors.

If it can do it at all. I know, heat pumps are really wonderful and all that -- but... you are pushing right at the limit of what it can do. Good luck.

GW

We do a bunch of minis—- I’m in Massachusetts

i agree with the above: set it and leave it alone. 

Condoman

I'm in eastern CT with 1,800 Sq Ft ranch. We have been between 20° & 45° my 4 X 7K + 1 9K are never touched & I can maintain 72°. They stay at that setting all season.