Sense has allowed me to evaluate something I have wanted to know
for some time. We hear how a heat pump running long periods of time
is more efficient than auxiliary or emergency heat strips.
I tested this tonight.
From 12 a.m. to 1 a.m. I ran just the heat strips with the heat pump locked out
During that time it came on a total of 17 minutes.
I then turned it back to heat and let the system decide to use heat strips to
supplement the pump. It ran for a total of 40 minutes during the 1 a.m. to
2 a.m. timeframe . It did not use the strip at all during that time. I was surprised
it didn’t being right at 20 degrees during the 12-2 timeframe.
At .085 KWH for electricity cost the strips used 4.9 KWH and use 15 KW.
The heat pump used 1.7 KWH.
So a heat pump uses, in my situation, about a third of the strips.
Two things surprised me about this little test.
- The heat pump did need supplemental heat with 20 degree outdoor temperature
and was able to pull enough heat on its own to maintain the house at 70 degrees.
- With as long as the heat pump ran (sometimes seems like it runs all the time)
that it was that much more efficient than the strips.
I was just curious, thought it might interest others.