HVAC question

mmcmdl

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I had a new AC / Heat pump system installed this past summer , got tired of having to hook up 7 portable units every summer . Always had the oil burner for winter . Question is , how does the electrical use compare to oil usage ? They came and filled up the tank and it only took 8 gallons . ( it was filled at the end of winter last year )

So this heat pump runs pretty much during the night when the wood stove is not running . Haven't got an electric bill yet and not knowing what to expect ? How expensive is the heat pump to run ? TIA The oil burner is suppose to kick in at a certain temp but it hasn't yet . :dunno:
 
I've got a decent heat pump w/oil furnace back-up. When outside temp drops to around 39-40 degrees the oil takes over. Cost of electric vs. no. 2 fuel oil? I feel pretty good $$$ wise.
When I had it all installed the contractor also hooked it all up to a digital thermostat. Works both systems as needed.
 
Yes , this thermostat is now digital. We were turning it down to 64 at night and up to 68 during the day . Seems like it runs forever in the morning to bring it back up to temp . Cheaper just to leave it at 68 all the time ya think ? New to all of this and the oil still hasnt kicked on although we had some 20 degree nights .
 
Yes , this thermostat is now digital. We were turning it down to 64 at night and up to 68 during the day . Seems like it runs forever in the morning to bring it back up to temp . Cheaper just to leave it at 68 all the time ya think ? New to all of this and the oil still hasnt kicked on although we had some 20 degree nights .
I'd guess that that thermostat needs looked at. Considering the price of fuel oil and electric it would be worth it I think.
 
Yes , this thermostat is now digital. We were turning it down to 64 at night and up to 68 during the day . Seems like it runs forever in the morning to bring it back up to temp . Cheaper just to leave it at 68 all the time ya think ? New to all of this and the oil still hasnt kicked on although we had some 20 degree nights .
Heat flows like a fluid from hottest to coldest. The rate is determined by the temperature difference. Keeping the temp up all night, requires the unit to run all night. Keeping the differential high. Let it cool down and you'll sleep better, (I believe 63 is optimal) and the differential drops.

Seems to run all morning, but it is just catching up from not running all night, and since the outside temps will be slightly higher, the heat pump will be slightly more efficient.
 
Heat flows like a fluid from hottest to coldest.
I did read that on the net , but coming from someone here I feel a little bit more confident about it . :encourage: Hopefully the electric bill won't be as much as the usual oil bill .
 
Heat pumps are kinda like cheap water pumps. The further uphill you pump, the slower it works, using more energy in the process, until at some point you just can't get there. Just substitute temperature difference for "further uphill". Or maybe a bicycle tire pump is a better analogy ...
 
Heat pumps are supposed to be the cheapest way to heat your house, but it will depend on the heat pump and your electricity cost. Some older heat pumps became inefficient at 35ºF (or around that temp). Below that, you used more energy to get the same unit of heat energy - it was break even around 35 degrees. Modern heat pumps can be efficient below the teens in deg F. Beware that some heat pumps used electric coils to provide heat when the pump reached its efficiency limit - then if your cost of electricity was high, the heat became expensive.
 
All new to me , but it was installed this year . I'll wait for an electric bill . The woodstove has been fired up lately which helps . Tomorrow I'll have a cardboard fire in the pit visable from NJ .
 
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