Yep, it’s loud! We could turn speed of our pump down but still noisy. You will learn to sleep through it 😬

Posted by: @bridgetjohn

Hello

We are in Buckinghamshire (a 1970's built house), moved there in August and changed from oil heating to an Air Source Heat Pump in November.  Its a Daikin Altherma 3M.  We've had some teething troubles with a faulty PCB board in the outside unit but that seems to be working now.  Its heating the house well, we've got plenty of hot water but inside the airing cupboard and in an adjoining bathroom towel rail, it's really noisy.  We had problems with a "snoring noise" which was fixed by the installer changing the pressure at the bottom of the buffer tank, but now the sound of circulating water through all the pipes in the airing cupboard and into the nearby radiators is really loud.  Any thoughts anyone?  Turning the valves in the towel rail off causes it to "snore" again.

Can't sleep when it fires up.  Any thoughts anyone?

 

thanks

It is possible that you have air in the system. there should be an air release valve within your system. It may also pay to bleed any radiators and towel rails.

I was going to say air in the system too. I have a Daikin Altherma 3H ASHP connected into our 20 year old radiators via a buffer tank. The installer bled the radiators initially but it took me a few weeks to get all the air out (even if auto bled valves in the loft). 
Do you get a glug glug glug sound as the system starts up?  I’m sure that is air. 
Do you have a separate pump from the ASHP that pumps around the radiators? Can you turn this down to see if that makes any difference?

@julianc Thank you.  I bled the towel rail and it let air out, but no change in noise.

I suggested air to the installer but they said not that.  Other radiators don't seem to need bleeding.

Its a rushing water noise round all the pipes in the airing cupboard and into the towel rail.  Radiators further away don't make a noise.

The pressure gauge at bottom of buffer tank was at 0.3 and it snored but made no rushing water noises.  At 0.4 it stopped snoring but was very loud.  At 0.5 its a bit quieter possibly but still lots of water noise.

btw I don't get a glugging noise, no.

I don't think there's a separate pump - I think its pump outside, buffer, tank and pressure vessel inside.

Posted by: @bridgetjohn

@julianc Thank you.  I bled the towel rail and it let air out, but no change in noise.

I suggested air to the installer but they said not that.  Other radiators don't seem to need bleeding.

Its a rushing water noise round all the pipes in the airing cupboard and into the towel rail.  Radiators further away don't make a noise.

The pressure gauge at bottom of buffer tank was at 0.3 and it snored but made no rushing water noises.  At 0.4 it stopped snoring but was very loud.  At 0.5 its a bit quieter possibly but still lots of water noise.

Hi Bridget,

After bleeding the air from the towel rail, did you top up the water in your system?

The required system pressure is normally around 2 bar. At what pressure did your installers leave your system?

@derek-m Yes, I topped it up and the installer has been back since to deal with a fault that occurred with disinfection.  It's currently at about 1.7bar

Posted by: @bridgetjohn

I don't think there's a separate pump - I think its pump outside, buffer, tank and pressure vessel inside.

An installation with a buffer tank would normally have a secondary water pump. Can you provide photo's of your system?

Posted by: @bridgetjohn

Hi Bridget,

It is difficult to tell from the photo's, but I believe the black object in the lower section of the first photo is the 3-way diverter valve and actuator, and not a water pump.

I assume that the upper large cylinder is the buffer tank, though it would appear that it is being used as a volume tank rather than a buffer tank, since it only appears to have one inlet pipe and one outlet.

I suggest that when the noise is present that you touch the various pipes to see if you can feel any form of vibration. Noise created when a liquid is flowing through a pipe is normally due to entrapped air, or vibration due to the velocity of the flow, or some kind of restriction like a partially closed valve.