Running a cold weekend on a mini split

[peakbagger]

The weather this weekend in NH was predicted to be an early taste of winter. Cloudy, windy and temps in the 20s at night. Normally I would crank up the wood boiler but with 2 MWhrs of credits in the bank from my solar systems I decided to heat the house with the minisplit. Normally I use it for supplemental heat. Its a one ton unit located on the first floor of my house. My office is on the second floor. In general it has worked well but equal distribution of heat around the entire house is definitely limited. The system kept up pretty well and on occasion I needed to turn it down as it was too warm. In general the real improvement would be to install a smaller unit in my office and then distribution would not be an issue and in general I would use less power as I wouldn't need to overheat the first floor. Its a one ton unit so at some point I will need to supplement it anyhow.

The other side effect of a cold weekend with minimal sun is that my solar hot water system gets to the point where the hot water is at best 110 degrees. Good for preheat but definitely too chilly for a shower. It does have electric element on the storage tank that I have never needed to hook up as normally by now I switch over to a hot water maker fed by my wood boiler or worst case my oil boiler. The weather is supposed to warm up but if I want to stay in this mode it may be time to hook up the back up element on a timer and give the tank a boost.

 

[semipro]

My office is on the second floor. In general it has worked well but equal distribution of heat around the entire house is definitely limited.

Have you consider installing a duct between the 1st ad 2nd floors under you office to move heat there?
You'd want to use a fire damper of course (e.g. below).

 

[peakbagger]

I have considered it but expect I can use the additional capacity of a second unit.

 

[peakbagger]

Update 11/29 and to date, the only heat I have used is the minisplit. No oil, no wood.

The major downside is I have to leave it running 24/7, no turn down unless its mild day and sunny.