8.5kW Shower flow

[seasickstevie]

Installed Triton 8.5kW to direct water supply in THIRD floor flat.
Turns out the pressure just ain't up to it!

What can I do?

Is it feasible to install a pump before the shower?

Apart from the pressure being pants, to make matters worse there are two other flats branched off the same single 22mm riser. How do I get out of this hole - please?

 

[Dan Robinson]

You will need to fit a tank and pump. Or an Accumulator.


Or move.

You CAN NOT pump the mains water.

 

[seasickstevie]

There is a storage water tank that feeds the bath & sink, although this gives only about 8ft of head (It's an attic flat).
Should I pump it from there instead?

 

[seasickstevie]

Thinking of the head-of-water issue from the storage tank, I suppose you measure from top of tank to the actual spray attachment, in which case we're looking at probably less than 1m, which is not impressive.
If I pump the Triton from the storage tank, I suppose I should take into account the size of the tank, as it will probably fill slower than the shower draws!

 

[TicklyT]

It's usual to measure from the base rather than the top the tank to the outlet.
It usually gives a slightly pessimistic answer, but it does indicate the worst case, which, as you will appreciate, will occur if the outflow rate from the tank is greater than the inflow.

You may be able to increase the fill rate of the cold storage cistern by fitting a second ball valve teed to the same supply.

The flow rate through an electric shower is usually quite low, restricted by the rate the unit can heat water at, but the supply does need to meet the minimum pressure criteria for the shower to work.

If you have stored hot water available, you may be able to consider a mixer valve specified as suitable for low pressure (0.2 Bar) supplies instead of an electric shower.

 

[Agile]

Cheapest solution is to fit a loft tank and a shower pump on the outlet from that.

If no loft then inside the flat. Sized for the max shower duration! Thats about 100 litres for a little over 10 minutes.

Then it would have to rest until the tank fills again in 20-30 minutes if you are lucky. Or fit a much larger tank for two showers.

Tony

 

[plumbswe]

If you are keeping the elec shower and go down the pump route make sure you read the manufacturers instructions for the shower regarding pressure. If its a Triton Cara I would try and take it back, they're disgraceful. Salamander make decent pumps

 

[seasickstevie]

Thanks for all the replies.

Just out of interest, why is it 'no way Jose' to pump off the main?

I have visions of the pipe under the street collapsing with the increased suction, and causing major traffic problems as the road surface collapses!





But maybe it wouldn't be quite as dramatic as that ...

 

[seco services]

Just out of interest, why is it 'no way Jose' to pump off the main?

It's illegal.

Change the shower with one with integral pump.

 

[seasickstevie]

Change the shower with one with integral pump.

I take it that would be one fed from the storage tank then?

 

[namsag]

Dont quote me on this but sure i have read somewhere that the mains can be pumped providing its not more tha 12 litres a minute.
Do a search on here i`m sure this is where i seen it

 

[seasickstevie]

Dont quote me on this but sure i have read somewhere that the mains can be pumped providing its not more tha 12 litres a minute.

I won't ...
...




(sorry ... couldn't help that)



Interesting ... thanks

 

[namsag]

//www.diynot.com/forums/viewtopic.php?p=1304780#1304780


Had a quick look for ya check this thread