Questions about heat pump for my shop

maple1

Minister of Fire
Sep 15, 2011
10,602
Nova Scotia
Heat pumps seem to work much better if they are on steady, maintaining temp. Rather than heating up a cold place. We are only running 1 of ours so far, temps lately have been between -5c overnight and +5c daytime. Cloudy days, and wind, can really make a difference when you're in the open.
 

peakbagger

Minister of Fire
Jul 11, 2008
5,629
Northern NH
Yes the recommendation is set it at one temp and forget it. A much larger unit is needed if used in a setback mode where the space is maintained at one temp when not used and expected to warm up higher temp on occasion. It may take 8 hours to warm up and in real cold temp it may never warm up.
 

JRP3

Member
Sep 17, 2007
205
Once the garage starts getting down near 50F my plan is to set the heat pump to run overnight at off peak rates. I'll set it for maybe 55 or 60F and see how it goes. I still have an electric heater and a wood stove if I really need to boost the temp higher. The unit is rated for 1000 sq ft so it is slightly oversized for my shop.
 

JRP3

Member
Sep 17, 2007
205
I set it for 62F, the lowest it will allow, and set it to come on around midnight and turn off around 6AM. Outside temps were down to 36 last night and still the same this morning, when I just went out to the shop and checked it was 54, about 3 hours after it shut off. Unfortunately it seems I can't set a regular schedule, just an on/off timer which I'd have to activate each day. Hopefully I can set a schedule with the app but I haven't been able to get that to connect, the wifi signal may be too weak in the garage for it to work, might have to boost it somehow.
 

JRP3

Member
Sep 17, 2007
205
My issue with the remote app turned out not to be my wifi signal but that I was using the wrong app. It's not the "MrCool Remote" app it's the "MrCool SmartHVAC" app. Had to contact Mr Cool support and have a somewhat difficult to understand conversation with a heavily accented foreign gentleman who helped me through the setup, (which was not straight forward), but it's working well now.
 

JRP3

Member
Sep 17, 2007
205
The other night and following day were in the mid to low 20's (F), I turned it on using the app at 4am and left it on for most of the day, kept the shop at 60+ no problem. Boosted it to 70 for a while just to see if it could and it did. One issue I've noticed is the app shows the shop temp to be 5-10 degrees lower than it actually is but the display on the actual unit is correct. Not sure if there is a way to adjust the app reading or not.
 

Deets

Member
Sep 7, 2020
129
Northern IL
I just got a senville mini split heat pump for my shed. Got it with 2 indoor units rated at 28,000 btu and 23 seer. Haven’t got it hooked up yet, did get the stand built though.
DEED524C-91FE-4B4A-92A1-40AAB4D80017.jpeg B795B87F-D88F-4A91-AED6-D7A254058D92.jpeg
 

peakbagger

Minister of Fire
Jul 11, 2008
5,629
Northern NH
I just got a senville mini split heat pump for my shed. Got it with 2 indoor units rated at 28,000 btu and 23 seer. Haven’t got it hooked up yet, did get the stand built though.
View attachment 267319 View attachment 267320
That is one heck of shed that needs 56,000 BTU of heating, that is way more than my house in Northern NH needs in minus 30 degrees.