Can I increase water pressure with a combi boiler ?

[ohmalou]

Hello everyone, apologies for this question but we are moving into a new flat and the water pressure in the shower room and the bathroom is very low, hence the flow is low too. The hot/cold water mix is working very well, but having a shower takes ages. The kitchen is fitted with a Vaillant Combi-Boiler. I have read that electrical/power/mixed showers will not work with a combi-boiler, and I am not allowed to install a pump as this is a mansions block and it will reduce the flow for the neighbours. Is there any solution to this issue ? There is no scaling in the shower heads. Many thanks for your reply.

 

[Burnerman]

If you have a combi boiler, you can only fit a shower that is suitable for mains pressure - i.e not a pumped one!
The pressure in your system (recorded on the boiler pressure gauge) refers only to the pressure in the central heating system.
If your water pressure is low, make sure that all stop cocks are fully on before considering other things.
John

 

[ohmalou]

Thanks for your reply - I will try to find the stop knock. Do you think it's worth calling a plumber to check all of this ?

 

[Burnerman]

With a combi boiler, to have hot water coming out, you need to have a plentiful supply of cold water going in...if this is restricted for some reason then the performance of the boiler will be poor.
However, if you have good cold water pressure at the other taps then this can be assumed to be ok.
You can't expect limitless supplies of hot water for a combi either, as it only heats whats needed...the hot water won't stop, but you won't get a bath filling deluge either.
One way or another, you need to see if your shower has isolating valves fitted to its incoming hot and cold supply, and check that these valves are fully open.
John