A Ductless Mini-Split or a Central Air Heat Pump?
How efficient is a central air heat pump vs mini splits?
I understand that having duct work increases losses but other than that?
In other words if a mini split has a SEER of 19 and a HSPF of 10 and a central air pump was the same rating and the central air pump had a variable speed and variable compressor. Would I expect to see performance differences in cold weather (below zero) and/or efficiency?
What about the temperature of the air that the units blow? Any difference there between the two units?
What kind of temps can I expect the fan to blow at these outside temps?
45 degrees
32 degrees
16 degrees
0 degrees
-15 degrees? Doesn’t have to be exact just trying to get some idea of what the air will feel like.
If a single speed central air heat pump had the same EER and HSPF ratings as a mini split what difference would I expect?
Looking at adding a central air heat pump to our vacation home in southern CO (81252) zone 6b I have a 95% propane furnace now but want to go ahead and add central air so I figured why not go ahead and make it a heat pump?
Last propane I bought was $2.94 and electricity there goes for .17-.19 kWh..
We keep the furnace on 50 all winter long and over the last two winters have used about 300 gals of propane annually . So about $900 for the propane and $100 tank rental. If the heat pump could heat the house the majority of the time and save money it might be worth putting it in vs just central air.. We are only there about 2-3 weeks during the winter months and use the fireplace then.
Also considering the same thing here at our Texas home. The furnace is 80% efficient. I am considering replacing it with a 95% propane furnace and adding a more efficient central air/heat pump with heat strips. My idea here is, to use whatever is cheaper at the time. If I get a solar system installed in the next two years I could use the excess to run the heat pump and/or strips as net metering stinks here.. Or if electricity goes through the roof, use the propane furnace. Here I use 12kWh of electricity per year and 400 gals of propane (heat, water heater and dryer) Zip 75020 zone 3A
Thoughts?
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Replies
In Texas, electricity should be cheaper nearly always and you’ll need AC anyway. The furnace serves no purpose and isn’t worth replacing. If propane was cost effective, it’d be used for electricity generation in Texas - it isn’t.
Similarly rated ductless and ducted units will be the same efficiency and air temps should be the same - probably 100+ degrees. However, you’re comparing a single speed central heat pump and a variable speed ductless unit. Why? You can get a variable speed ducted unit in both “traditional” and “minisplit” outdoor forms.
In CO, electricity looks to be 50% cheaper than propane at 70 inside. At 50, the heat pump will be even more efficient.
What about a ducted mini split?