shower and combi boiler All aspects of plumbing questions and answers, help, tips and information

[oldpj100]

I've just bought a modern shower cubicle with an large overhead jet, and several side ones. The problem is we have a combi boiler which doesn't produce a strong enough flow to make a suffiecinet hot feed. I am unsure if a pump would help as the boiler might struggle to heat the water as quick as the pump pulls it.
Someone suggested a seperate hot water tank (we live in a bungalow so the only place is the loft) to use for the feed, along with a pump. We have good pressure on the cold rising.
Can anyone help???

[Arnak]

Hi,

Yeah, combi's without sufficient pressure are a problem with showers. :cry:

Fitting a pump would not work as it will draw water to fast from the boiler to be effective.

Putting a tank into the loft is not on as you will also need an immersion cylinder to store the hot water as well.
This will not work well with a combi boiler as they are not made for that type of system.

I had the same problem in my house, I only cured it by fitting a very large boiler.

The pressure in the hot and cold should be the same as far as I know, with a pressure valve fitted on the cold supply to the boiler to cap it at about 2.5 bar.

With small boilers and large mixer showers with all the bells and whistles a high output combi is required.

Not much help in my answer I'm afraid.

Arnak

[oldpj100]

thanks for that arnak. so short of buying an expensive new boiler i'm stuck! I thought a dedicated immersion tank in the loft might be a cheaper option. do you know if building regs allow an immersion in the loft?

[oldpj100]

thanks for that Arnak.
So short of buying an expensive big boiler i'm stuck!
I thought a dedicated immesion (not on the CH system) might be the cheaper option?
Do you know if building regs allow an immersion in the loft?
thanks
pete

[Arnak]

Hi,

I'm not sure on that point to be honest but that could also be a bit of work as you will still need a header tank and that will need to be higher than the top of the immersion cylinder.

So you will need to raise that on a platform. :(

You should be able to check the building regs on line or call a plumber and ask his advice.

Arnak