Shower waste pump

[StepOne]

Hi,

We have a shower waste pump installed beneath our wet room floor which has been leaking. The wet room is part of a loft conversion done by the previous owners and the pump is used to send the water up and over the roof to the waste pipe at the back of the property.

Under normal use there is no leak, but if you stay in the shower too long (15 mins?) which my daughters do, then the pump will cut out, and the water will cease to drain away. The pump will full up with water (I guess) and at this point the leak occurs. After a while the pump will click back into action and the water drains away.

In addition, when in use, the pump is quite noisy in the room below (which is a bedroom) and also our adjoiinging neighbours complain about it. The fact it sits between joists seems to create an echo chamber effect, and the sound travels through the walls.

We have finally decided to do something about this, and so have had the ceiling in the room below removed in order that we can access the pump without lifting the wetroom floor. A plumber has taken a look and said we need to replace the pump (it's approx 10 years old), but they can't do it for 2 weeks.

I'm wondering if the pump actually needs replaced. The leaks only happens when the pump overheats and cuts out. The overheating issue must be partly due to lack of airflow as the pump is between joists, and is hard up against the chipboard above. Will try to link to a couple of photos of it. The first is the waster water side entering the pump and the second is the outlet side.

https://photos.app.goo.gl/JQzKewQV9hkGeSfN2

https://photos.app.goo.gl/gVjlmJHANvB43Csu2

I'm wondering if we can mount the pump differently it might improve airflow, and if we can somehow 'suspend' it instead of sitting on plywood attached directly to the joists it may help reduce the noise. I'm also thinking that I should be able to do this myself, rather than wait 2 weeks for the plumber.

Also I'm thinking that even when it cuts out, the pump should not leak (I think the water overflows at the top somewhere) so maybe there is just a missing/worn seal that could be replaced, which may be obvious if I can get the thing out.

Does anyone have any suggestions on how I could do this?



Thanks,
StepOne

[csearle]

Sorry can't help. I just feel that building a piece of electrical equipment into a space inaccessible for maintenance is not a good idea. Is there no way it could be located elsewhere, i.e. in a more accessible location?

Regards,
Chris

[Devjon]

Looking at the pictures you linked to I'd be concerned at a leaking pump in a box that also contains the pump motor and electrics.

I would try to do as Chris suggests and install a new pump in a more accessible location. If the pump is 10 years old as you say then the seals / bearings are probably on the way out. ( I spent the best part of 50 years repairing Electric Motors / Pumps / control systems etc )

If the pump is resonating enough when running to annoy your neighbour then I would see that as another reason to replace and re site.

[StepOne]

Thanks for the comments. I have since got hold of the local Saniflo approved guy who is going to come out on Monday and take a look at it - he mentioned replacing seals etc. He said that if they do cut-out , they will overflow, which I was a bit surprised about. If he sees it on Monday and advises replacement then we will do that.

Also, we have come to realise that the piece of chipboard directly above the pump is accessible in a crawl space behind the wetroom. Although there is no hatch we should be able to cut away a section to allow the pump to be serviced, and probably leave that section open which will hopefully reduce the risk of overheating.

Re-siting might be preferable, but will just be too much cost and effort at this stage, especially as there is now (since this week) a very realistic chance that we will be looking to sell this house imminently!

What I would like to do, though, is look at how the pump is attached to the joists. See photo of the view from below. The pump sits on a piece of plywood, which is attached to two batons, one on each joist.

https://photos.app.goo.gl/kO6tv7MIIV0v3ZMa2

If the pump has to sit on plywood, is there any way to attach this to the joists, using some kind of rubber fixing to reduce vibration? I'm already thinking to get an anti-vibration mat to put between the pump and plywood, but in addition I would rather not have the battons screwed directly into the joists. . I've googled anti-vibration fixings, but do not know enough about what I am looking to know if they could be used to do this job. Is anyone able to post a link to a product on screwfix which could be used to attached the plywood base to the joists via rubber dampening system somehow?

Thanks very much,
StepOne

[Devjon]

These are similar to what we used to use from time to time to dampen vibration from electric motors.

Not sure about the space you have around the pump. I have worked on a few Sanilav / Saniflo systems, not the most pleasant of tasks working on the Sanilav units :-0 ( though I still shudder at the memory of the Industrial slurry pump that came into the workshop from a pig farm...)

https://www.amazon.co.uk/BQLZR-Rubber-D ... tion+mount

One thing I would say is that from memory the Sanilav units were always noisy even from new as they tended to use small pumps and drive them flat out.

[csearle]

If the pump has to sit on plywood, is there any way to attach this to the joists...

How about straddling the joists with thick bands made of rubber and attaching a smaller ply base to them in the middle with the pump thingy attached to that?

Regards,
Chris

[StepOne]

These are similar to what we used to use from time to time to dampen vibration from electric motors.

https://www.amazon.co.uk/BQLZR-Rubber-D ... tion+mount

Those are the kind of things I have seen. I'm just not sure how to attach them to wood. Would they screw in if I drilled a pilot hole? And, even if I did that, how do I then screw the other side in, without unscrewing the first side? Sorry if that sounds thick, but I just can't see how to actually use these things and googling 'how to use..." hasn't helped.

StepOne

[staffordian]

These are similar to what we used to use from time to time to dampen vibration from electric motors.

https://www.amazon.co.uk/BQLZR-Rubber-D ... tion+mount

Those are the kind of things I have seen. I'm just not sure how to attach them to wood. Would they screw in if I drilled a pilot hole? And, even if I did that, how do I then screw the other side in, without unscrewing the first side? Sorry if that sounds thick, but I just can't see how to actually use these things and googling 'how to use..." hasn't helped.

StepOne

I doubt they are designed to be used as such, but I imagine you could drill a pilot hole the diameter of the solid part of the bolt into the joist and the thread would cut a "thread" in the joist. Do this with four of the mounting blocks.

You could then fasten the plywood that supports the pump to these mounting blocks using metal right angle brackets, screwed to the plywood base, and use nuts to fasten these brackets to the mounting blocks.

[Itsallaguess]

What I would like to do, though, is look at how the pump is attached to the joists. See photo of the view from below. The pump sits on a piece of plywood, which is attached to two batons, one on each joist.

https://photos.app.goo.gl/kO6tv7MIIV0v3ZMa2

If the pump has to sit on plywood, is there any way to attach this to the joists, using some kind of rubber fixing to reduce vibration? I'm already thinking to get an anti-vibration mat to put between the pump and plywood, but in addition I would rather not have the battons screwed directly into the joists. .

I've googled anti-vibration fixings, but do not know enough about what I am looking to know if they could be used to do this job. Is anyone able to post a link to a product on screwfix which could be used to attached the plywood base to the joists via rubber dampening system somehow?

Given that you're always going to have some sort of transmission path from the pump no matter what you do with vibration-damping, in the form of the pipework itself, then I'd start small here and see how things improve as you go.

I think some minor adjustments in the mounting arrangement will prove to be a big help in the noise department, but you're always likely to have at least a low-level background noise I would think, unless you start to isolate sections of hard pipe-work with flexible rubber sections, which may of course be something you want to investigate later on.

I'd look to remove the plywood underneath the pump altogether, and use something like a couple of galvanised roof-tie straps (https://tinyurl.com/yb7uxrsg), positioned so as to pick up the pump feet, and this would then give you much better access from underneath to then continue your noise-damping experiments. It looks from your photo like the access from below would be pretty good for these types of tasks, if you could only get that plywood out of the way to get better access to the pump and pump feet.

Once that's done, I'd look to just get some rubber mounting feet in between the pump feet and the galvanised straps (https://tinyurl.com/y82kaqky), and initially just see how that's affected the noise, but I'd expect an improvement straight away at that point to be honest.

A couple of strips of old carpet underneath the rubber feet would help some more. The above rubber feet and strips of carpet method is how I've mounted my large bathroom extractor fan in my loft, and it made a hell of a difference for just a couple quid....

You still want a decent clamping arrangement through the pump feet, the galvanised strapping, and the carpet/rubber-feet combination, but I think that would improve matters quite a lot, and also enable better access for future maintenance for normal pump-work, as well as noise-dampening experiments....

Cheers,

Itsallaguess

[csearle]

...

A development of Its's arrangement that I have used with noisy extractor fans is to sandwich loft-insulation between the screwed-together solid bits. Dampens all manner of vibrations. Never had a complaint from customers (maybe they're too scared though?).

Regards,
Chris

[jfgw]

With shower (supply) pumps, I usually place the pump on a paving slab or something similar, and place some damping material between the slab and the floor. I have used one of these, https://www.screwfix.com/p/salamander-p ... 50mm/2480p , and found it to be excellent (which it should be for that money).

Some sound travels through the air so a sound-insulating box can make things almost silent. Allow enough clearance and ventilation so that the pump does not overheat.

As has already been pointed out, sound will travel along a pipe. It appears from your photograph that the manufacturer of your original pump has provided suitable vibration isolation (at least, on the outlet), https://photos.google.com/share/AF1QipN ... xYdUtEa2JB .

Julian F. G. W.