A quiet central heating pump?

[ABCwarrior]

Can anyone recommend one? Our bedroom has the pump in it, its a Grundfos 15-50, don't know if this type is a decent make? Would the much more expensive "Alpha 2 15-50" be quieter?
It doesn't help that our thermal store etc is located behind some thin sliding doors, not in a dedicated well built cupboard, so there's little scope for sound reduction.
Might be cheaper and easier to re-jig the cupboards...?

 

[muggles]

Grundfos are widely accepted as being the best there is, it should be quiet, so it might be getting worn/mucky or the pipework might be vibrating rather than the pump itself

 

[ABCwarrior]

It's only 2 1/2 yrs old so probably ok? Just noisy especially as we live in the middle of nowhere at night it's lovely and quiet then it kicks in and keeps me awake!
How "quiet" do you mean- suppose it's all relative but should it be heard at all or be totally silent in operation?!

 

[muggles]

Should be near-silent but of course it depends on how sensitive your hearing is! As I said before, it could also be the pipework vibrating rather than the pump making a noise

 

[Boilerman2]

In my experience - with the exception of where the pump is literally worn out, noises are seldom caused by the pump, causes of noise are
1) Air in system (faulty design of feed & vent pipes?)
2 Pipe brackets either side of pump attached to plasterboard walls/ Studwork, these wall amplify noise hugely
3) oversized pump - fitting a massive pump to overcome design faults

Grundfos make one of the quietest pumps on the market

 

[ABCwarrior]

Will investigate later. Reviews on that dearer pump on screwfix say it's very quiet though?

 

[muggles]

As far as I can see from a quick Google they're both rated at 43db, so they're identical sound-wise

 

[dcawkwell]

Simply move the pump.
Problem solved. Simples.

 

[ABCwarrior]

Change our bedroom to the one at the other end of the hall would be the solution!!

 

[samba12]

Did u try turning the pump speed down? theres a selector on the pump with 3 speed settings

 

[ABCwarrior]

Didn't know that- is that what the slot on the front is for? More to the point this could be a good temporary solution to our sh*gged thermostat problem, if I turn it down to the lowest setting it may slow down the rate at which we lose our hot water...

 

[mysteryman]

Check that it is fitted with the spindle pointing slightly up from horizontal, and the water flow should never be downwards. The speed control is a little selector switch on the terminal box.

I used to think Wilo pumps were a bit quieter when I was installing.

 

[oilman]

I would avoid Wilo pumps. Have had several fail recently with seized impeller or impeller coming off shaft.

 

[SimonH2]

I'm guessing that this is a fixed speed pump you have, and it's feeding the heating which has TRVs, and it's running from a thermal store ?
With this setup then I'd suggest a fixed speed pump is the last thing you want - when teh TRVs throttle down then you either need a bypass (not good for store efficiency) and/or the system gets noisy.

I put an Alpha 2 modulating pump in the flat when I put a store in, and it's hard to hear whether it's running or not ! When the TRVs throttle down, it spins down and drops the pressure - so no noisy TRVs etc. I also did away with the room stat and fitted a TRV on the last of the rads. The TRVs now provide full temperature control of each room, and the boiler only fired when the store temperature drops.

Note that there are two Alpha 2 pumps - there's the Alpha2 and the Alpha2L. The L doesn't have the night time set-back feature* which puzzled me as the instructions that come with it didn't mention this - leading to me not being able to reconcile the instructions with the actual control panel. Plumbing merchants aren't familiar with then either, and probably don't know about the two models.

* I think the idea is that if you have a system that drops the flow temperature at night, the pump senses this and also turns itself down.