How noisy is your heat pump
On the back of BridgetJohns post, it would be good to hear from ecodan owners how loud your heat pump is. The outdoor heat pump itself is pretty quiet but when it’s operation the internal pumps are pretty noisy with high pitch humming sound. Have learned to sleep through it now but I do wonder if flow rate is set too high and it’s not supposed to sound like this

Well I've got an Ecodan. The heat pump outside is really quiet, but even so I can't even hear any internal pumps in action.
105 m2 bungalow in South East England
Mitsubishi Ecodan 8.5 kW air source heat pump
18 x 360W solar panels
1 x 6 kW GroWatt battery and SPH5000 inverter
1 x Myenergi Zappi
1 x VW ID3
Raised beds for home-grown veg and chickens for eggs
"Semper in excretia; suus solum profundum variat"
We have an 11.2kW Ecodan. I noticed that the compressor was notably louder at lower ambient temperatures, eg approaching and below 0degC, due to the compressor being required to work harder.
I made some enquiries about the "Quiet Mode" option in the controller. Apparently on Ecodans it simply limits the compressor speed to reduce maximum noise output. Obviously this also reduces the maximum capacity of the heat pump.
As our heat pump has been conservatively sized, I decided to trial the unit set to full time Quiet Mode. So far it has operated fine when set on the quietest option, including when we had sub-zero temps for a few days in January. The unit is noticeably quieter now too.
Mitsubishi Ecodan 11.2kW R32 ASHP; Ecodan DHW cylinder; UFH+rads
20x430W Jinko TOPCON Tiger Neo solar; Luxpower 6+4kW hybrid inverter; 20kWh LFP battery storage
Posted by: @skdWe have an 11.2kW Ecodan. I noticed that the compressor was notably louder at lower ambient temperatures, eg approaching and below 0degC, due to the compressor being required to work harder.
I made some enquiries about the "Quiet Mode" option in the controller. Apparently on Ecodans it simply limits the compressor speed to reduce maximum noise output. Obviously this also reduces the maximum capacity of the heat pump.
As our heat pump has been conservatively sized, I decided to trial the unit set to full time Quiet Mode. So far it has operated fine when set on the quietest option, including when we had sub-zero temps for a few days in January. The unit is noticeably quieter now too.
Just to add, our DHW cylinder is also Ecodan. The three pumps were supplied by Mitsubishi as part of the pre-plumbed package. They all have a slight hum when operating but none are intrusive...even with the radiator circuit pump set to max flow.
Mitsubishi Ecodan 11.2kW R32 ASHP; Ecodan DHW cylinder; UFH+rads
20x430W Jinko TOPCON Tiger Neo solar; Luxpower 6+4kW hybrid inverter; 20kWh LFP battery storage
We also have an 11.2kW Ecodan. Generally very quiet except when the ambient drops. We only have one internal pump (something I am still trying to get rectified by our installer) and it does make quite a bit more noise than I would like, although I have also learned to sleep through it!
I wish we had had the opportunity to have the pre-plumbed Ecodan cylinder installed, but I don't think it would have fitted into our airing cupboard.
All decent heat pumps are variable speed, the outdoor units are quiet on warm days and noisiest when it's cold and wet. Indoors they should be pretty much silent.
The water pumps are very quiet when running. If you can heat them either there is air mixed in the water, you will hear noises like a tap running. It's super hard to get the air out. I would install a spirotech deaerator if you have this issue.
If you have water flowing noise in your radiators your system needs balancing. Balancing is easy but rarely done anymore. It's very important with high water speed heating like heat pumps.
Sounds like you need to call the installer back for a mid season tweak.
Good luck.
Heat pump expert
It is a very loud humming noise, which is louder when water is heating. No radiator s, all underfloor heating.
that is not good, you need the installer back. i have 4 pumps on my heat pump all in the same cupboard, i cant heat mine, there is something wrong with your system.
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