Identifying Electrical Signature of Heat Pump Components

Morning! Sense has recently started identifying portions of my air source heat pump (specifically Mitsubishi P series ducted 42,000 BTU system, one indoor air handler tied to outdoor condenser).

I am wondering the best way to differentiate between the electrical components of the heat pump, such as the compressor, condenser, blower, reversing valve, etc. My principal question is, what clues can I use to decide which part is drawing power? Do some parts draw more in heating vs. cooling? Which parts make up small portions of overall energy usage vs large portions? What differences in the signal can I expect for different parts?

Any information is welcome! The compressor and fan are both variable speed which I imagine will make them more difficult to identify.

One part sense identified draws consistently 440 watts, and appears to only be active in heating mode. It is consistently on at 440 watts while the heat pump is active. I originally suspected it was the blower, however the fan is variable speed, and the 440 watts is constant. In addition, the 440 watts appear to only show up in heating mode.

Any ideas? Any advice or insight would be greatly appreciated! I am eager to track the heat pump’s energy usage as I am running my own personal experiment to prove an ASHP can be cheaper than natural gas in Colorado. Thanks in advance!

The P series (PUZ) … The one your talking about has an invertor that runs a scroll compressor and the outdoor fan together, making them “variable speed.” The outdoor unit should all show up as 1 device. In cooling mode, the outdoor unit is your condenser. The reversing valve is a low voltage switch and sense will never see it, the transformer that control the outdoor unit also provides the voltage for the reversing valve, if it could be measured. I would guess 0.0001 watts.

The outdoor unit in heat mode at 75% with the indoor fan running at Med-Hi will pull the same amount of wattage as 75% cooling with the indoor fan running at Med-Hi

It also has a defrost cycle while in heating mode, but you should have no problems being cheaper than natural gas until it gets very cold

In heating mode, the indoor unit is your condenser. Your indoor fan has 4 speeds and its a regular 120v multi-speed motor. Sense may find each speed separately but might not.

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Thank you for all the great info! That makes sense that it will be impossible to identify the reversing valve.

The 400 watt component I assume is the indoor blower then, as the outdoor unit would be drawing more power in heating mode.

Do you know if any other part of the indoor unit may be identified by sense? Thanks for all the advice!

I used the dedicated circuit monitoring to watch my air handler but Sense has not identified my air handler/fan.

I think because Sense doesn’t see the initial on spike of the air handler and the compressor as 2 diff devices?