Help with reducing noise on a pump

mjkinch1

mjkinch1

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Not strictly a boat, but hopefully someone can help me. We have just installed a new Salamander water pump next to the tank in the airing cupboard - and its a bit noisy. (it boosts the water presure)

I have some dense foam blocks which I have put under the feet, but its still makes a reasonable amount of noise, both vibrating through the floor and general pump noise.

When I was at SIBS I saw some anti vibration mats - are they worth getting? Also I thought about building a box around the pump to contain the noise better - any ideas about what is best to insulate it with - Polystyrene/Foam/egg boxes

The pump wakes the whole house up when it comes on - so any help really appreciated !

Martyn
 
Two main points .....

1) Most pumps supplied are "silent" ... so is your noise correct or a fault ?

2) .......I have a well supplied pump-water system to my house .... yep - Perrier on tap !

I have same problem with noise from the pump ... but being in the cellar it doesn't intrude so badly as yours appears from your post.

We thought of boxing in etc. - but were advised that it is not so simple matter .... a) you need to keep a free flow of air over the motor and through its fan, b) where we drop to extreme cold in winter - we have to be careful to allow warm air to flow around the motor and pump.

We were told that it is possible to build a box using thin ply / OSb and line with insulation such as rockwool etc. Leaving the base open ... so basically building a lid and sides to drop over the top ... BUT the box must be with a lot of free space around the pump .....

As put to me apart from air-movement .... you have to be careful not to create a "boom-box" ..... that is a chamber that actually deepens the sound and literally amplifies it !

It is also noted that some of the sound is actually generated by the pump and travels the pipe-work .... illustrated to me by the plumber !! Not much - but enough !
 
Thanks for that. I think you are right, part of the problem is vibration through the pipes, but I am not sure if I can do much about that, as they travle the length of the house.

The pump is not essentially noisy, but at night it can vibrate through the house with a humming sound, and certainly waked me and SWMBO up! We have stuck a timer on it so it only works during the day, but its a less than perfect solution.

Martyn

Would it be worth raising it off the floor completely? (wooden floor).
 
Have you checked the manufacturer's website so see if they have any suggestions? Or phone the manufacturers when they get back from hols. Most have good technical depts.
 
I take it the pipework is all copper at the moment. What about installing a bit of plastic piping with some bends in it at either side of the pump to absorb some of the vibration?
 
Copper water pipes can transmit pump vibration very well, so it may be worth investigating whether you can change the pipes both sides of the pump for plastic pipe. MDPE is available in 25mm for mains water supply, whilst PE-X is available in 15, 22, & 28mm. It might also be possible to connect using the type of stainless steel braided flexible pipe tails supplied for use with shower booster pumps, which might be even more effective at damping the vibrations.
 
yes - raising it off the floor would help - but only if on a base that won't transmit the noise straight to the floor again.

Same story with the pipes - a suitably flexible connection may help reduce the pump noise - although for example on my boat the pressure pump has short lengths of flexible (the nylon reinf. pvc) before the copper; & it doesn't help much. Car heater hose, otoh is much better, as it has more give & seems to absorb the vibration as much as insulate from it.

If possible, get some helping hands & see what improvement you notice if you unscrew the pump from the floor & support it just clear with your hands. If your helping hand's ears report a great improvement - you'll know where to start - but getting results as good as (assuming it does help) manually holding it off the floor may need some trial & error .

I'd hope to screw it to something heavy yet flexible to absorb some of the vibration & thence to the floor via rubber mounts. If it moves very much in use, then flexible coupling in place of the copper wd be a good idea anyway.


All based on things that did/didn't work very well on our steel boat.
 
Many years ago - before they were at all common - I fitted a shower pressure booster pump and made a wooden base with shallow sides, the whole thing being lined with carpet underfelt. The pump was screwed to a matching wooden base which fitted snugly into the recess in the "sub-base". I cut rubber connecting hoses from a Hillman Imp radiator hose - that tells you the vintage! It all worked well and was pretty quiet.
 
Thanks everyone - I wil call the manuf. tomorrow - and I think I may replace the initial pipes with plastic, which may absorb some of the vibration.

Martyn
 
If you are talking about a shower pressure booster pump the output and inlet on both the hot and cold impellers should have been supplied with flexible pipes that couple to the copper and insulate the pump from vibration. The pump inself should have rubber feet and be free standing. The problem is what to mount it on and this is all about mass. Go to B&Q and buy a big heavy flagstone. rest this over the joists and pop the pump on top. I guarantee it will stop the transmission of noise to the joists and via them to the rest of the house! Anti-vibration mats won't work and a flagstone (or even a big floor tile if there is no room) is far cheaper. Trust me and try it! it works!
 
I have flexible couplings from the pipe - so I will try the flagstone approach, the floor is strong enough to take it. I got the lad to hold the pump slightly off the floor when running, and hey presto a lot of the noise went. So off to B&Q tomorrow to try it out.

Thanks
 
If you are on floorboards rather than directly over joists a bit of carpet under the flagstone will help too. Let us all know how you get on. I think you will be surprised!
 
Thanks all - that Plumbing forum is really good - I will use that again, amazing what you can get online!

Slab gets fitted Thursday complete with carpet - so will letyou know the outcome!

Martyn
 
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