Do you have an air source heat pump tank like this (photo) and should it be making a noise?

[DecisionTime123]

Looking at buying a new build, it's got a "box" in the garden and then this is in a cupboard in the main bedroom. I know these systems are meant to be great but when I looked round this week, it was making an electrical "whining" sound.

Is it normal for these things to make a noise all the time, will it get worse when in use?

Is the noise coming from the big tank or either of the expansion tanks above it, or perhaps from the pipe work.

what kind of noise is it?

Is that the hot water system? Bit annoying to have it in the main bedroom if it makes a noise!

@tanstaafl I don't think there is a definite way of knowing, when you look into the cupboard it's just a "noise" like an electrical "note"? Its coming from around the tank maybe?

I had one fitted this year and it doesn’t make a noise at all.

It looks like its a Vaillant brand. Find if there is a FaceBook group for Vaillant Air Source Heat Pumps (the box in the garden?) and describe the issue and see what they say?

That looks to me as if there is a ASHP with microbore pipes and high pressure system- ie it looks like my airing cupboard.
We don't get noise in the house, unless it is doing a Legionella cycle - much quieter than the old oil system. Ours is a Mitshubishi ASHP which we've had for 6 years and happy with it.

That looks like an unvented water tank for the hot water.
We have one in our NB and it did make a bit of noise at the beginning but my OH had a look and it was because the water temp had been set too high (the adjustment had been turned up against the stop), he turned it down a little and it stopped running continuously.
Ours is in an airing cupboard on the landing.

Have had this message from developers (sales office though):

"In relation to the cupboard housing the hot water tank and pump, this area is insulated in line with current building regulations. While there will naturally be some level of heat and operational noise from these systems, they are installed and tested to ensure compliance. One option would be to turn the system off overnight if the noise or heat becomes a concern. However, this can cause the system to work harder in the morning and may result in higher running costs."

Is this is a reasonable suggestion?

The most efficient way to run a heat pump is generally (once you’ve got the settings optimised) to leave it running all the time. It’s much less efficient and costs more if it’s going on and off so that wouldn’t be a solution for me.
That said I don’t notice any noise at all with ours regardless of how hard it’s working.

We have a Vaillant and both pump and tank are silent - it's so cheap to run. They're great pumps.

No, its a ridiculous suggestion. ASHP need to be left on all the time, although our system is set to run at lower temperature at night. The thing about ASHP is that they will take a while to get up to temperature again, as the whole system runs at a lower temperature so if its turned off overnight, it could take until lunchtime until it warms up again.
Its worth reading up on ASHP- I think we started with the energy saving trust, but it doesn't explain the noise.