Need help with a shower water pump

[PapaLazaru]

Builders are coming in next week and doing a lot of renovation work, including a complete bathroom refit.

My cold water pressure (mains fed) is very high (almost too high to be honest) so the builder has said that a pump would be good to regulate the flow of hot water (gravity fed) to both the bath mixer tap and and the shower they are fitting.

I want to buy a Stuart Turner Monsoon pump due to the fact that they are very highly rated and come with a good warranty (and are a local firm).

The question is, am I likely to need anything more than a 2 bar pump and would getting a 3 bar pump be overkill?

I need to order it asap so any advice would be helpful. Money is not a concern as I can get the 3 bar pump for a tenner more but am more worried about overkill on the hot water pressure.

 

[Participant]

The main factor here is the capacity of your hot and cold water storage tanks. 3 bar will make for a very nice but very short shower, if your cylinder / tank is too small.

If these are sufficient, I would always go a 3 bar as I like a gushy-wushy skin-stripping shower. You can always use the shower valve to regulate the flow I suppose, but it's better to have storage to match the flow rates produced by a 3 bar shower.

Fyi they won't be pumping from your cold mains; this is illegal I believe...they'll presumably be pumping hot and cold from storage tanks.

By the way, Stuart Turners are indeed the shizzle.

 

[PapaLazaru]

I think you are right having had a look at the setup. The cold is gravity fed but the cold water tank is in the attic and does provide immense pressure. The hot comes out of a tank in the bathroom in a cupboard and is therefore a lot weaker. We are getting a decent sized square thermostatic showerhead but I do not want it taking too much hot water.

I think I will go for the 2bar.

This one in fact - http://www.bellabathrooms.co.uk/stuart-turner-monsoon-shower-pump-2-bar-single.html

Just need to get the air vent bought now (have not got one at present) and my bathroom will be complete.

I already have the complete bathroom suite (shower bath), flooring, tiles, lighting and mirror cabinet sitting in my lounge waiting for them to come round whilst I bugger off on holiday for the week.

 

[Participant]

I think you are right having had a look at the setup. The cold is gravity fed but the cold water tank is in the attic and does provide immense pressure.

Immense pressure from a gravity fed cold supply in the attic? Unlikely, unless the tank is 30m above the shower!

I'm guessing from your description that the cold will be fed from the mains with the hot supply from the tank in the cupboard.

They should be running a dedicated feed from the cold tank in the attic and from the hot water, not teeing off existing connections as this will cause flow problems when other outlets are used whilst you are showering.

Ensure they use the correct connections to the hot water tank and do not tee off somewhere that will cause aeration problems.

 

[Django x2]

You have a cold feed to a storage tank which will feed your hot water cylinder and probably most of your toilets. True pressure for could would be evident at your kitchen sink, as this would come straight through the 25mm pipe (blue) before going off to the CWST.

Very modern houses, I suppose, would tee off at each floor so that the pressure for toilets, sinks, baths and showers was all under pressure, but most are fed from the CWST too.

A pump will work, we looked at one, in fact, we had one (1.5 bar) and it was shocking. If your tank is in the bathroom on the top floor, you should look to install the pump alongside it. If you have to have it back up in the loft, it will lose a bit of pressure. It will also be loud, so you should investigate a concrete slab and anti vibe mat for the pump. Whole house pumps are a good idea if you are at that stage but again, even flushing the toilet at night will generate noise.

We ripped out or pump and I installed all the new pipe work for a mains fed hot water system using an unvented cylinder. Because I did most of the pipe work myself, (I'm a copper pipe artist ), I saved a load of dosh. We replaced the HWST with a aluminium Joules 205litre tank which was little more than the cost of a good pump.

For pumps, I love a good old Grundfos

The key to good pressure is to keep the blue 25mm pipework constant (with little or no joins) all the way to the tank. I ran a single piece of 25mm pipe up 3 floors to the new tank through the boxed in sections of a soil stack poo pipe (which ran from the garage al the way to the loft).

If adding softners, this can affect pressure as the pipe has to reduce to 15mm for the softner, but it is only a short process so shouldn't impact pressure too much.

 

[Participant]

The key to good pressure is to keep the blue 25mm pipework constant (with little or no joins) all the way to the tank.

That's the key to good flow, not pressure. Pressure reduces as flow increases.

If adding softners, this can affect pressure as the pipe has to reduce to 15mm for the softner, but it is only a short process so shouldn't impact pressure too much.

A pipe reduction to 15mm increases pressure rather than reducing it. Flow is reduced, pressure is increased.

But yeah, wider pipes are better for a decent shower.

 

[TFC]

We have just had one of these installed, Unvented cylinder system, it is not a cheap option, but it has to be the best upgrade I have ever done.
we have between 6.5 and 7.5 bar pressure from the meter, this is reduced to 3 bar at the house, this system then supplies balanced 3 bar hot and cold through out the home with no need for any water storage tanks in the loft or elsewhere and no need for noisy power shower pumps.

 

[Participant]

^ That's what I want in my house. Currently running a combi, which is a bit rubbish as it changes flow when people flush loos etc.

How much did that cost you?

 

[TFC]

How much did that cost you?

£2700 inc VAT and installation for a 250 litre fully plumbed cylinder which also upgraded the heating system as well.

Flushing the loo, starting the washing machine or even running a second shower have no effect whatsoever

 

[Django x2]

So, you've had mains pressure hot water fitted. That's all that is, as per my post.

The tank was £500 (Joule 205 litre Slimline), pipework I did myself, but initial quote was £3k for everything including a water softener at £400. Eventually came in at £1500 which was for all the parts and labour.

As much as I'm in agreement with TFC about additional water demand, it doesn't cure that problem completely, nor claim to. If the main kitchen tap was run, for instance, it would reduce flow/pressure to the shower's, marginally, but the temperature will remain balanced.