Mitsubishi Heat Pump - What did I miss?

Old 08-15-22, 05:54 AM
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Question Mitsubishi Heat Pump - What did I miss?

I'll try to make this short as possible.
I have an MSZ-FD25VA pump, it should heat and cool, but doesn't.

It's an old pump, but things I've checked everything seems fine until things hit the inside unit.
I measured the pipes (copper pipes) both in heating and cooling mode and all the way to the indoor coil it shows 54c (130ish F) in heating mode and 16c (60ish F) in cooling mode, for an old pump I'd say this is fine. But the indoor coil itself never changes in temperature.
I've cleaned the coil with soapy water, degreaser and put good amount of water through it to flush out all of the soap out but that didn't help either.

Things seems to be pointing towards indoor coil that is bad, anyone else have the same thought?

And IF it was low on refrigerant would the copper pipes be that hot / cold all the way up to indoor coil?
Is there any fix for this or is it "dead" pump?

Thanks for any answers, ( from Norway btw and no technicians could answer above questions )
Old 08-15-22, 07:00 AM
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The techs should recover and weigh the charge to verify its correct.
I don’t know what would be “bad” with the entire coil. The metering device is in the outdoor unit.
Old 08-15-22, 08:01 AM
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Yes they probably check to see if anything is missing etc. But wasn't sure if anyone had any ideas I could do before I take the step to pay an technician to check it / fill it.
Old 08-15-22, 09:11 AM
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If the lines get hot or cold it means there is flow. I can't see that happening without going thru the coil.
Old 08-15-22, 09:55 AM
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Maybe sounds like the reversing valve is stuck or not working properly.

(I'm honestly a bit outside my knowledge zone, but it seems this unit has one, and my understanding is that it allows the coil to get hot or cold depending on heating/cooling).
Old 08-15-22, 10:33 AM
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PJmax; To clarify my measurements - > I measured the lines from the coil outside all the way right when they get inside (in wall) but the indoor coil doesn't get colder / warmer, just the lines .. if you understand what I'm talking about (bad english on my end perhaps).

Zorfdt: reversing valve is working, otherwise it wouldn't deliver cold / hot temperature through the lines(?)

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