Power Shower..please help

[scott77]

Hi all,

I am asking this question on behalf of a friend without internet access so i'll put you in the picture first...

He has recently bought a new 2 bed house which was designed and fitted with a gravity fed shower, unfortunatly its just not man enough for the job it just trickles and so does everyones on this new estate.
Everybody complained so their answer was to fit a power shower pump the problem is their saying there is no power supply unless they use the immertion heater supply which obviously means he will no longer have an immertion heater which he and I think is totally unacceptable.

The question is.. is it a big nono to power the pump + immertion heater from the same supply at the same time??
we would have thought it would need its own supply but we have no idea what sort of power consumption these pumps have?

Many thanks in advance for replies
scott

 

[securespark]

Scott a radial circuit for an immersion heater is designed for that load only, so you will need a new circuit for the pump.

The ones I fit with my partner-in-crime (builder) are 700 ish watts and you fit a 5A fuse in the FCU.

I fit a Powerbreaker H92 rcd spur, usually outside the bathroom, but don't mount it where it can get overheated ie adjacent to tank.

You could use a 6A RCBO to feed the pump from your CU.

Where will you mount the pump?

 

[Big_Spark]

Forget my post, I misread the original

Thanks Ban

 

[ban-all-sheds]

It sounds as if the water pressure is insufficient for the amount of homes they built, if this is the case, a Power Shower will not solve the problem as it still needs water to pump.

Err - no. It's a gravity fed shower, and so nothing to do with mains pressure. Almost certainly because the cold water tank is in the loft and therefore provides a head of only a couple of feet for the shower.

A pump will fix that, but whether the hot water cylinder holds enough for more than 1 person to have a shower at a very increased flow rate is, of course, another matter...

 

[AdamW]

Surely the best solution would be to spur off a ring circuit to install the pump? Sounds like the developers are trying to save themselves £10 on a house worth £100K's by fobbing people off instead of rectifying their balls-up. This is odd, however. A gravity system will always give the same pressure provided they jack the cold tank up high enough in the loft. I.e. it isn't governed by mains pressure, just the head. So the developers should have foreseen this.

After reading this thread I had a lightbulb in my head go on, so went and had a look at the supply to my immersion heater. Turns out the funky gibbon who installed my power shower for the previous owners spurred the pump supply off the immersion heater supply... get this... with FLEX!

Of course the plumbing work in my installation appears to be top notch. This backs up the post about plumbers not requiring electrical knowledge despite being expected to install showers and macerator pumps.

Never mind, I ripped all the old bathroom out today so there will be some PROPER wiring going in now!

 

[ban-all-sheds]

1) Many modern shallow pitched roofs have so much timber in them (so that the cheapskates can use 2x2 rather than 6x4) that you'd struggle to lift a tank very high, or find any roof timbers able to take the load.

2) It may contravene some illogical regulation, but provided the total load does not exceed the capacity of the cable, and provided an FCU is used as appropriate, there is nothing unsafe with having a shower pump on the immersion heater circuit

3) There is nothing unsafe with using flex. If there was then you would not be able to buy either fixed appliances prewired with flex or flex outlet plates.

 

[AdamW]

3) There is nothing unsafe with using flex. If there was then you would not be able to buy either fixed appliances prewired with flex or flex outlet plates.

I didn't explain that one fully. The person who installed it used flex to daisy chain an FCU of another FCU, I am pretty sure T&E should be used in this situation as it is fixed wiring.

 

[scott77]

in response to securespark "Where will you mount the pump?"
the builders have mounted the pump 5'high above the tank in airing cupboard and because my friend refused them to use supply from immertion heater its sitting there plumbed up but not connected and hes waiting for the developers decision....
adamw, your first reply is on the button, they have made a huge cockup and now trying to bodge it!!
anyhow i will post the outcome if they ever decide....
many thanks for your replies
scott

 

[AdamW]

Just happened to have the manual for my shower pump next to me (Not because I'm some kind of geek, I installed it the other day!) and I quote this from it:

"The pump must be positioned as close to the base of the hot cylinder as possible, ideally pushing water not pulling"

Your last post says they installed the pump above the hot tank. Obviously all pumps are different but I think they may have performed a less-than-ideal installation here.

I must say I admire your friend's mettle! Along with 99% of the populous I would probably have ignored the flagrant bodge and just let them do it knowing I could claim for damages if their work ended up killing me.

 

[AdamW]

the hot water cylinder holds enough for more than 1 person to have a shower at a very increased flow rate is, of course, another matter...

Anecdotally, I have a flat intended for no more than 2 people to live in and thus it does not have an exceptionally large cylinder. I once had no less than 6 people stay here and we all showered the next morning, sequentially, with a power shower, with me being last. I had no lack of hot water which is entirely immersion heated, and I am notorious for taking ages in the shower. Admittedly it was summer but I doubt anyone went for a cold shower so 3 showers should be fine in winter.