Cost to operate heat pump

I have a three ton Goodman heat pump that I would like to estimate the cost of operation for a period of time, say one hour, without activation of the heat strips. The unit is a 16 SEER and was serviced in 2018 so I believe it is operating at its best efficiency. How can I estimate/determine the amps the unit draws so I can calculate the wattage? Is additional information needed to make the estimate? I would expect to disregard any electrical costs of the defroster if it would trigger in this time frame.

If determining the amp draw is difficult, can anyone put a knowledgable ballpark estimate for one hour operation at 15 cents per KWH?

Thanks

 

From what I’ve seen, heat pumps use less than 3kw an hour for just the exterior unit. At 15 cents per kWh, you’re looking st about 45 cents for the hour. Assuming the unit runs for a full hour.

I’m still new at figuring all these costs out, so don’t take my word for it.

Contractor said my 20,000 watt furnace would cost $4 an hour to use at 20 cents per kWh.

I assume you’d also need to add in the cost of the air handler fan.

 

Determining the amp draw isn't difficult. It's stamped on an ID plate on the unit.

 

Thanks Pete, but isn't the boilerplate rating the maximum it can draw but not necessarily the actual draw?

 

There are several ratings.... one is LRA - locked rotor amps - which is maximum and the second amp rating is the actual draw.

A 3 ton heat pump would likely draw around 20A when running. That would be 4800 watts.
The blower runs roughly 4A. That would be 480 watts.
4800 + 480 = 5280 watts = 5.3 kw x .15 = $0.795 hour. Eighty cents an hour.

 

Thanks, Pete: I had wondered what that second amp rating meant.

Your math works out closer to 80 cents/hour. (5.3 x .15 = .795)

 

Ummmm..... could it be new math.