Combi boiler - how can i increase the pressure in shower

Aquatronixjenny

Bad choice of boiler. My sister has that boiler in her 3 bed 1 bathroom house and it's only just enough for that.

har0ld

If the boiler is able to heat the house and you have plenty of pressure to the basin and kitchen taps - don't worry about the boiler size (although I have a smaller house with the greenstar 42 as i always go a little overboard)
The key thing is that your waterfall shower heads require far more water than even many of the large combi boilers can deliver. if you want to improve the perceived pressure you need to use a smaller shower head! (think thumb on end of garden hose, the volume of water stays the same but the smaller you squeeze down the end of the pipe - the higher the pressure becomes.)
A company called hansgrohe specialise in mixing air with water to give the illusion of a waterfall - they aren't cheap but they are good. hansgrohe give you the flow rates for all of their shower heads and you need to get yours down to roughly 12-14 litres/min based on a worcester 28.
hope that this helps

ic

I have a slightly bigger boiler than that in my two bed, one shower, 8 radiator terrace house. What a mistake your plumber has made!

tommy619

You could change the thermostatic shower valves to manual valves and put a TMV valve on the system. This would thermostatically control all the showers and taps in the house and you should see a boost in water pressure in theory.
Do not change to electric showers. Most you will get is 7 litres per minute.

travellerboy

You have identified the down-side of a combi-boiler, low hot-water flow.

There is NO way of increasing this flow other than accept a lower shower temperature or changing the boiler to a very much higher flow rating. The cheapest option is to get an Electric Shower with maximum KW rating. Your current combi-boiler should be fine for the other household uses.

Owain_Moneysaver

travellerboy wrote: »

You have identified the down-side of a combi-boiler, low hot-water flow.

There is NO way of increasing this flow other than accept a lower shower temperature or changing the boiler to a very much higher flow rating. The cheapest option is to get an Electric Shower with maximum KW rating. Your current combi-boiler should be fine for the other household uses.

But an electric shower will be ~10kW max. That's about a third as good as the boiler - and electricity is about 3x the cost of gas so it will cost more per litre of hot.

It will also need a plumber and an electrician to install.

The sensible option is to change the shower heads to ones that are less profligate with water.