I have a heat pump with propane as my back up source of heat. I have been setting my propane to kick in at 32 degrees and lower. Heat pump runs at all temps above freezing. Since my electricity is 7 cents/kwh and my last fill up of propane was $2.55/gal, I am thinking I might be much better off financially if I lowered by temp of when the propane would kick in. Oh, my propane furnace and and pump were the highest efficiency Lennox's I could purchase in 1995.
BackUp Heat Question
- Thread starter Gebo
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So you have an external thermostat as well? Unless you are getting some weird water freeze up, does the heat pump care about the freezing point of water? I know a heat pump will struggle when it gets really cold, but unless it's underdesigned for the size of your structure, it should do OK into the 20's.
Personally I would do it by internal temps - because when my house is full of sweaty mammals, and we are cooking dead mammals, computers on, showers going, TV's, etc - it easily raises the temps (but we are pretty well insulated)......
Personally I would do it by internal temps - because when my house is full of sweaty mammals, and we are cooking dead mammals, computers on, showers going, TV's, etc - it easily raises the temps (but we are pretty well insulated)......
JHZR2
Staff member
sure, thee is some heat that is stored by virtue of the mass of the walls furniture, etc., but do you really want to chance the freezing of anything in your house, should there be bigger issues?
Electric heat is notionally 100% efficient. It would be good to know the efficiency rating and lower heating value of your fuel.
JMH
Electric heat is notionally 100% efficient. It would be good to know the efficiency rating and lower heating value of your fuel.
JMH
Pablo,
There is a thermostat that I can set to determine when the propane furnace takes over the heating. I have always set it at 32 but with the high price of propane, I am thinking it would save me expense if I keep letting my heat pump run down to say 25 degrees F.
My hp is a 12+ something or other and my propane is a 92% efficiency.
There is a thermostat that I can set to determine when the propane furnace takes over the heating. I have always set it at 32 but with the high price of propane, I am thinking it would save me expense if I keep letting my heat pump run down to say 25 degrees F.
My hp is a 12+ something or other and my propane is a 92% efficiency.
I am in a similar boat. I have purchased propane the last two times for $1.79/gal. Electricity is 7-7.5 c/kWh. My York unit is 15 SEER and 92% AFUE. It is currently set to switch to propane at ~ 36°F.
Is there a rule of thumb or formula based on cost of electricity & propane with efficiency thrown in to determine optimum temperature setting?
Is there a rule of thumb or formula based on cost of electricity & propane with efficiency thrown in to determine optimum temperature setting?
Even if you were using emergency heat 100% at 7 cents per kw that's the equivalent of 1.83/gal of propane. soooooooooooshut off your propane period..its a no brainer. Heat pump will function some even at 20 degrees..thats even more gravy.
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Electric heat is not 100% efficient.
Unless you use superconductors, and then there would be no heat!
Unless you use superconductors, and then there would be no heat!
Close to 100%:
Quote:
Because electric resistance elements are nearly 100 percent efficient, the efficiency of electric water heaters depends on the how well they are insulated.
http://www.bchydro.com/business/investigate/investigate824.html
Quote:
Because electric resistance elements are nearly 100 percent efficient, the efficiency of electric water heaters depends on the how well they are insulated.
http://www.bchydro.com/business/investigate/investigate824.html
How do you get propane for $1.79/gallon? It's about $3.25 here, delivered. Oh, must be special Canadian metric propane.
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