Power shower from a combi boiler?

[viz48]

My son is adding a second bathroom and want to have an all singing all dancing power shower. He has an oil fired combi boiler....large capacity but has been told he cant have a high powered pump with a combi boiler. he is talking about putting in water storage tank and normal boiler (extra) in the part of the house that will have the new bathroom. A whole separate system!! This seem a bit extreme!!! Anyone any experience of this??? Thanks

[buildersmate]

Sure it could be done, but it is rather extreme.
Combis are good at supplying a decent volume of hot water at say 50 degrees. But if one wants to exceed this rate of flow (and having a power shower is likely to demand huge water volumes) then they are no good.
I assume his plumber has checked the rate (volume) of water flow out on the boiler spec. and advised him accordingly.

[gucciman]

i'm a gas engineer rather than a plumber but i do see a whole host of different systems when i'm in peoples houses.
does he have a shower running of his combi in the exisiting bathroom? i was under the impression that combi's can provide quite a powerful shower as they are, much more so than an electric shower, esp if he has a powerful boiler of 30kw or more.
another option may be to convert his existing system to include a water storeage cylinder in the loft to give him greater flow and pressure, the combi could then heat the cylinder and perhaps he could have an additional high pressure pump from the cylinder to the shower.. this would be cheaper than an extra boiler and cylinder and power shower pump.
or he could have a system boiler put in and an unvented hot water cylinder to give mains pressure water which would give him a great flow of hot water to every tap and shower, again cheaper than 2 seperate systems and boilers.
my advice would be to pop in to your nearest plumbers merchants and ask the counter staff there for their advice, note down what make, model and power output of boiler you have to make it easier for them.
also ring a couple of plumbers and ask them for a free quote and the different options.

[gasman]

Gucciman there is a big difference between a power shower and an electric shower the power shower will provide a far greater volume of water and pressure than any combi could ever provide. The combi is however better than the majority of electric showers, that depends on the wattage of the shower. but also the combi is only as good as the incoming water main so if you happen to be in a low water pressure area then even the biggest combi could be a poor delivery of hot water. You're idea of running a stored supply off the existing combi is halfway there but you would have to re-design the system and introduce zone valves, seperate programmers and seperate thermostats aswell as the header tank, the cylinder and the twin impeller pump to the thermostaic shower. But it does save on installing a totaly new independent system where you would still need all the above along with the additional cost of the new boiler as well.

[tezestwing]

hi viz just another point to bear in mind I agree with all the other post and as they have said it will require major alterations and additions.
One of which as the gasman pointed out would be to fit and upgrade the size of the main storage tank in the loft to suit the extra demands of power pump etc and depending where it is sited on the joist they may in turn have to be beefed up to take the extra weight of stored water, at a cost HTH Tez

[gucciman]

thats fair comment gasman, i'm still training, learned loads but still lots to learn yet especially on the plumbing side. i'm glad to see you back, always learn a lot from your posts.

[gasman]

Cheers gucciman keep up the good work and keep training mate you are allready as i have noticed very knowledgable and I am sure once fully quallifed you will make an exellent Gas Engineer. Even after my 24 yrs in the game I am still learning !!! Hope you didnt mind my comments, just trying help you out a-bit.