Hot water basebourd + heat pump?

[slayman]

We are finally going to install central AC. With the skyrocketing cost of fuel oil I am considering adding a heat pump as well. The intent being to set it up to run the heat pump down to "x" temp, then switch over to oil. What's the easiest way to determine payback?
If the answer to this question is here somewhere please point me in the right direction.


Thanks

Slayman

[beenthere]

There is no easy formula for a dual fuel system.
With PPLs current electric rate.
A heat pump will generally heat for 1/3 the cost oil would down to about 40° outdoor temp.
And about 1/2 the cost of natural gas.

[slayman]

Thanks Beenthere,
In the back of my mind I'm thinking about the rate increase coming in what 2010 or 11. At 1/3 the cost (electric vs oil) I'd have 3 years to pay back the additional cost of the heat pump. That is probably feasible, but I guess I'll have to dig into the btu's needed for heating on days above 40 + or - and compare the cost of oil and electric.

Slayman

[beenthere]

Although electric will skyrockt in 2010. Oil won't be as cheap as it is today either.(can't believe I used cheap and oil together)

If electric were to go up to 25 cents per KWH, and oil was 4.50 a gallion.
A heat pump would still be cheaper at temps down to 35 to 40* outdoor temp.

Heat pump at a COP of 2.0 (most heat pumps are closer to a 3 at 35 to 40*)would be $3.66 for 100,000 BTUs.
Oil at 82% efficiency and $4.50 per gallion would be $3.92 per 100,000 BTUs.

[flange]

I have oil fired boiler in my own home with baseboard, and central ac. At the end of summer i will be installing an 18 Seer heatpump and VS air handler. in place of the ac unit. The difference is I get to buy the equpment for cost as I am a contractor.

[beenthere]

I have oil fired boiler in my own home with baseboard, and central ac. At the end of summer i will be installing an 18 Seer heatpump and VS air handler. in place of the ac unit.

Sounds like DIY.

You gonna add a hydro coil too?

[flange]

Actually, i will have my fitters do it when it gets slow for a few weeks. Typically right around the end of September before we start boilers. Not adding hydro as it is located in a very cold attic, and my intent is to run the heatpump down to about forty, then go to oil. I will however put in some fancy controls to change it over just for fun. Cant help it, I am an old control guy at heart.

[beenthere]

On several heat pump installs where they have CI rads.
We put in 5KW of strip, so they can run the HP at temps that will require defrost.
They still save more on their total heating bill doing it that way, instead of just locking out the HP at 40.