Will we have a longer shower if we change the pump

[BeckyG]

Hi,

Please excuse my ignorance!

We have just had a new bathroom fitted and the main reason for getting it done was to improve the shower, so we bought a showerforce 3 bar pump from B&Q.

However now the bathroom is all done it seems the max length shower we can have is 8 minutes before the hot water runs out. This is completely unacceptabe as it only just gives me enough time to wash my hair, never mind my husband have a shower!!

I do not know what capacity the hot water cylinder is, but the dimensions are 480mm diameter, and 1050mm in height.

We were wondering if we changed the pump to a 2 bar pump instead would this give us much longer or not? Is there a way we can work this out?

All help much appreciated.
Becky

 

[petit_pablo]

Changing pump wont magically produce extra hot water. You need a bigger cylinder

 

[simond]

Yes, the lower the flow rate through the pump, the longer the hw will last.

You could restrict the flow through the pump a bit using the isolation valves, if you were going to bin it anyway.

The other thing you could do is turn up the stored water temp to 75 degrees in the cylinder. Ultimately it will cause limescale deposition but it does increase the energy storage capacity of the cylinder.

 

[Hugh Jaleak]

Does the water go cold after 8 mins or does the water peter out altogether? Im thinking that 1050x450 cylinder holds 140litres of water. Assuming its mixed 50/50 with cold, and there is a cylinder stat set at 60C 1/3rd of the way up cylinder, then this gives approx 90 litres of hot from the cylinder + 90 litres from cistern in roof. The shower is putting 22.5 litres a minute out to use that lot in 8 mins. Reducing the pressure would reduce consumption.

 

[Gasguru]

Your cylinder is probably around 140 litres capacity. Based on a 60/40 mix ratio of hot (at 60c) to cold water this should give over 200 litres of useable shower water.

Measure the flowrate into a bucket...10 to 12 litres/min is normally perfectly adequate.

Is the cylinder heated by immersion heater? If so the thermostat can be faulty turning off the heater before the cylinder is fully up to temperature (normally 60 centigrade) or the timeclock is not on sufficiently early to allow the cylinder to heat fully.

If the cylinder is heated by the boiler is the thermostat clipped about a 1/3 of the way up? and set to around 60 centigrade. Is the boiler thermostat set to a sufficiently high tempoerature. Does the timeclock allow sufficent time for the cylinder to heat up fully?

Setting the thermostats above say 65 centigrade can damage the pump.

If you have valves on the pump OUTLETs you could throttle these down or you could fit a restrictor to the shower hose/rose.