r-32 heat pump in zone 5-6
I’m considering adding a ductless heat pump to my house. A goal is to go with r-32 because of the phaseout of r-410a and some difficulties I’ve heard about sourcing its replacement. However, all I can find are Daikin models that bottom out at 5F for their normal operating range, and it looks like they fully shutdown at -4F according to the spec sheets.
I’ve done an informal survey around my area and it seems most folks are running hyperheat or halcyon heat pumps, which makes sense because my ASHRAE design temp for heating is -4F. However, the house does have a very nice wood stove that provides the bulk of the heating BTUs during winter, and I’d be willing to install some baseboard or wall electric heaters in the bedrooms that are farther from the stove. I’m also coupling the install with some efforts to improve my very poor wall insulation and add air sealing where I can. And historical weather data suggests an average of around only 20 days annually where the low is below 5F.
So I’m leaning towards just installing the daikin unit and muddling through with backup options for the coldest nights. Does this sound reasonable? Are there important things I’m not considering?
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We're installing 8 heat pumps at our church. Originally planned to go with the new refrigerant but most units are still at r410a. No one seems to know when everything will be changed over so now we have a mix of units. R410a will be available for a long time so I wouldn't worry about that.
As far as your plan, do you have any load calculations? If you don't need the heat pump at those low temps then sure your plan is fine. We're in zone 4a and have only done cold climate with out back up heat
There are some more out there. Search for LG KSSAL121A . Rated down to -30F and nameplate at -12F.
I would look for either r32 or r454 units, R410 will be around for a while but I see no point in locking in on an old refrigerant. There will definitely be more selection during the coming year.