Pump under bath

[2scoops0406]

Senario, new bathroom. Wall mounted taps, insufficient flow to fill bath in reasonable time (> 15 mins), solution install pump under bath for taps, pump is IP44 rated and manufacturers have said it is suitable for under bath installation, bath is raised off floor, now space wise it is possible. What is the best way to wire the pump in? Due to bathroom design, not possible to electrically connect pump outside the bathroom. Crimps, sleeving, tape and chock blocks ok?

Pump will be connected to RCD side of CU, bathroom has been cross bonded. Sorry a bit terse, can't be bothered to type too much, off out soon

Not my house BTW.

TIA

 

[breezer]

why not put the pump near the water tanks

you are not allowed to pump mains water (i learnt that in the plumbing forum)

 

[2scoops0406]

'cos it needs both hot and cold pumped

 

[securespark]

As Breezer points out, you cannot pump mains. If your cold water has such a shoite pressure, you should investigate the cause.

If the mains cold has poor pressure, maybe that's why the hot has too, if the hot comes from a combi.

 

[breezer]

'cos it needs both hot and cold pumped

that is why i said tanks, not tank.

pumping mains water sounds a good idea, but if the water pressure is low the pump may pump faster than there is water available, it can in some cases create a vacuum, and normal air pressure will squash anything with a vacuum,
in other words the pipes will be crushed by air pressure.

its rare but it does happen, aparently quite spectacular if it does it to a hot water cylinder.

the way round it is to have 2 water tanks one for the hot and one for the cold and pump these. the tanks not being sealed will never crush and the pumps will empty them and just suck in air.

but as was also said the solution in this case is to find out whay the available water is so feeble, may be a partiail blockage or existing tanks too low, anyway i am not a plumber.

 

[TicklyT]

Have you thought about changing the taps for ones suitable for the water pressure available? Sone taps are designed for 'mains pressure' supplies, so don't work too well on gravity supplies, whereas other outwardly very similar designs have bigger waterways suitable for gravity feeds.

 

[bernardgreen]

If the mains pressure is low then the advantage of a loft tank and indirect hot water for all but drinking water supplies is well worth the cost of installing them.

To have no hot water because the neighbours are using water and your combi cannot fire up due to low mains pressure is not a way to start the day.

Pumps can fail. Gravity doesn't ever fail......

 

[2scoops0406]

Ok, thanks for the replies.

The taps require high pressure feeds, the taps are installed and are not going to be changed. Neither hot nor cold water feeds are from the mains, one being from the loft tank, one being from the hot water tank.

The problem has been solved by installing a negative head pump in the loft, thus negating any electrical zone problems. All working fine.

BTW, it's not my house.