Rattling noise from central heating pump

Graeme1978uk

We live in a 3 storey new build property. The boiler is on the ground floor and there is a hot water cylinder on the middle floor. The cupboard where the cylinder is has the pump and 3 valves for each zone (hot water, master bedroom heating, rest of house heating).

Over the last couple of weeks, I've noticed a rattling sound which seems to be coming from the pump, however it only appears to be doing it when the master bedroom zone is on. If just hot water is being heated or the rest of the house, there is no rattling at all. It's only when the heating in the master bedroom is on.

Now the company that installed all this are utter cowboys, we've had no end of heating and plumbing problems since we bought the house last  year so anything and everything should be considered when suggesting a possible cause!

Is it just likely to be the pump that is the issue or could there be other causes?

Bendy_House

If it's a newish install, it's unlikely to be the pump itself, at least not if it's been installed correctly - there are some angles/directions which are not recommended.

Photo of pump in situ?

Have you tried bleeding the bedroom rad (pump and boiler off whilst doing this).

Is the master bedroom on the top floor? What pressure is your system set at? When you try a bleed, note how forcefully the water is ejected.

FreeBear

Agreed, unlikely to be the pump.

As the noise only occurs when the bedroom zone is active, I'd be looking at the zone valve - It could be sticking and in need of a spot of oil (don't use WD40). Are the bedroom radiators getting hot ?

Graeme1978uk

Bendy_House said:

If it's a newish install, it's unlikely to be the pump itself, at least not if it's been installed correctly - there are some angles/directions which are not recommended.

Photo of pump in situ?

Have you tried bleeding the bedroom rad (pump and boiler off whilst doing this).

Is the master bedroom on the top floor? What pressure is your system set at? When you try a bleed, note how forcefully the water is ejected.

Thanks for the reply. I did bleed the radiators first - there are 3 on that zone,
two in the bedroom and one on the en-suite. No air in the bedroom ones and a little in the en-suite. Once the air was finished the water just trickled slowly out. Photo of the cupboard attached. The valve for the top floor is lowest one in the photo, but the rattling is definitely from the pump side.

Graeme1978uk

FreeBear said:

Agreed, unlikely to be the pump.

As the noise only occurs when the bedroom zone is active, I'd be looking at the zone valve - It could be sticking and in need of a spot of oil (don't use WD40). Are the bedroom radiators getting hot ?

Yeah they are heating normally by the looks of it. The rattling is definitely coming from the right hand side (see photo above)

Graeme1978uk

I’ve uploaded a short video of the noise….

https://1drv.ms/v/s!AiPZy0hMa6CQgagC-ceLOmWlTo_jzw

NSG666

With the other two zones off, does the noise start as soon as the master bedroom zone turns on or only after a period of time? Where is the thermostat for this zone? Do the rads have TRVs on them?

When it's chattering does it stop as soon as you turn on another zone?

Graeme1978uk

NSG666 said:

With the other two zones off, does the noise start as soon as the master bedroom zone turns on or only after a period of time? Where is the thermostat for this zone? Do the rads have TRVs on them?

When it's chattering does it stop as soon as you turn on another zone?

Yeah the noise starts as soon as zone switches on. The thermostat for this Zone is in the master bedroom and is a Tado wired thermostat.

Out if the 3 rads on this zone, only the one in the en-suite has a TRV on.

Sod’s law, I’ve just activated this zone to see if it stops when another zone is active, and the noise didn’t start when the heating kicked in, but I think it does to it intermittently anyway maybe. Next time it’s making the noise I’ll kick another zone in and see what happens.

Graeme1978uk

TRV’s don’t make any noise?

Bendy_House

TRVs can make a noise, but really only if they are faulty - ie a loose washer inside, or an early non-bi-flow type fitted on the wrong end (guess how I know...)

As you say, tho', that noise does appear to be from the pump itself.

FreeBear

Bendy_House said: TRVs can make a noise, but really only if they are faulty - ie a loose washer inside, or an early non-bi-flow type fitted on the wrong end (guess how I know...)

You put one on the wrong end of the radiator didn't you

When you do that, they make a heck of a racket and it sounds like someone is hammering away at the radiator. A lot more noise than the OP is experiencing !