Heat Pump Sudden Power Use Increase

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rendezvous

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Master Geek
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#323032 18-Oct-2025 21:27

Hello,

We had two Panasonic heat pumps installed a year ago. The Panasonic app shows power usage and cost on the monitor tab. The past few days the lounge heat pump has been showing around 270W usage per hour when turned off, as opposed to around 10W per hour prior to that. The heat pump is definitely off, with flap closed. No unusual lights or messages anywhere. I know “other” can include drying mode, but this has not been used in this case.

Any thoughts?

Goosey

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#3426130 19-Oct-2025 07:25

What’s the outdoor unit condition like?

any moss/mould etc etc on the unit?

have you tried switching off the outdoor unit for a few hours?

timmmay

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#3426138 19-Oct-2025 08:33

Is it really using more power? Do you have any way to test it? My office Daikin heat pump reports it's using 270W when it's turned off sometimes, but I assume it's just a false reading since it's not doing anything.

rendezvous

197 posts

Master Geek
+1 received by user: 50

#3426140 19-Oct-2025 09:16

I have switched it off outside - I’ll turn it back on later and see if it starts reporting power use again. The outdoor unit appears fine, not all blocked up - I can understand that would increase the needed effort to cool or heat, but I can’t see how that would affect power use while turned off

In terms of confirming whether it’s using the power or just reporting it, I can look back at the hourly use on my power app as well. I could find two hours with nothing else on, have the heat pump switch on (but still not doing anything), then switch it off again and compare the two hours. I would need to probably turn the hot water off too as to try and get more reasonable comparison

Goosey

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#3426188 19-Oct-2025 09:42

Is the hot water powered by the same heatpump?

remember the outdoor unit although not running still uses a tiny bit of juice to keep it ready.

rendezvous

197 posts

Master Geek
+1 received by user: 50

#3426266 19-Oct-2025 11:24

Hot water is just a standard electric cylinder, not a heat pump one.

yes, it’ll use some power when off for sensors and being on wifi. That’s the change I’m asking about. Previously it was 250-300Wh for the whole day, the past few days it has been reporting to use that much per hour, which is 6-7kwh for the day - $43 a month of power if it was off! The power it is using while running heating/cooling seems about right.

tweake

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#3426281 19-Oct-2025 12:52

also check if your model has a crankcase heater. if you just had a cold snap, its possible the crank heater turned on to help keep the oil warm and help with the gas/oil separation.

Lenovo

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Goosey

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#3426468 19-Oct-2025 19:46

Compare the app data to your power company data to see if the heat pump app is reporting correctly.