Is this noise from Mitsubishi ducted heatpump normal?

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Kookoo

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#322829 26-Sep-2025 22:17

We just moved into a new build which has two Mitsi ducted heatpumps side by side. One sounds like any other heatpump, but this one has this weird whine that changes tonality based on fan speed if I was to guess. It gets loud enough for us to have to switch it off at night.

For those of you with Mitsubishi heatpumps - is this normal?

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aspett

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#3419063 26-Sep-2025 22:20

The file isn't public, but ducted heatpumps are pretty loud and we always turn ours off at night. We had issues with a neighbour's being far over the noise limits during the evening.

Kookoo

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#3419066 26-Sep-2025 23:39

aspett:

The file isn't public, but ducted heatpumps are pretty loud and we always turn ours off at night. We had issues with a neighbour's being far over the noise limits during the evening.

Thanks, I changed it to public now. That's a good point - the other unit we have next to it is just a normal through-wall heat pump for the lounge. Between the two, the ducted one is way louder with this very distinct whine. I wonder what's causing that.

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timmmay

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#3419097 27-Sep-2025 08:24

Heat pumps make weird noises from time to time, but I wouldn't call that normal if its doing it all the time. I'd get the installer out to check them.

Our 10kw Daikin ducted heat pump is inaudible from a few meters away. Unfortunately it's quite close to our bedroom and the low pitched noise does make it into our bedroom which bothers my wife a little but she's gotten used to it, but we leave it on overnight otherwise the house gets cold.

openmedia

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#3419217 27-Sep-2025 11:09

What model do you have @Kookoo?

i had a similar issue and in the end it was a bad compressor that they had to swap out. The company I used had revived a bunch of bad units and they all needed repairs.

Now It occasionally gets a little loud and generally just need a push on the case as the compressor has been moving around.

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Kookoo

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#3419229 27-Sep-2025 13:38

openmedia:

What model do you have @Kookoo?

i had a similar issue and in the end it was a bad compressor that they had to swap out. The company I used had revived a bunch of bad units and they all needed repairs.

Now It occasionally gets a little loud and generally just need a push on the case as the compressor has been moving around.

It's a FDCA100VNP-W

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aspett

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#3419253 27-Sep-2025 15:53

That doesn't sound particularly abnormal for ducted heat pumps honestly. If you've not had your unit serviced recently/ever, you should: it does need to be maintained. Perfect opportunity to get them to look at the noise. They might be able to play with the compressor or add insulation.

Council has pretty much told us that residential ducted heatpump noise is actually a pretty big problem because they are big and noisy, and placement of units isn't part of resource consent which means you can accidentally screw yourself or your neighbours with poor placement.

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shall0w

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#3419824 29-Sep-2025 17:21

I had a brand new mitsubishi ducted unit (14kw? ish) installed a few months ago, makes the same noise and varies based on load. I was surprised at how loud it was but seems that's the norm.

BuzzLightyear

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#3419858 29-Sep-2025 20:14

We have a mitshi ducted and that's exactly what it sounds like when it's working quite hard. If you turn it on and it has to work to get to the right temperature it works pretty hard and then it backs off. If it doesn't ever back off or slow down it's worth getting looked at.

See if it actually gets the room(s) to the set temperature. Once it has the unit should slow down.

When my installation was done several years ago the temperature sensors were set to read off the indoor unit in the ceiling vs. the average temperature of the control unit or room sensors. Because of this it was always working hard. I found the settings in admin and changed.