Combi Boiler & Shower

[leevis]

Hi All

Need some help understanding something here. I am currently building a loft extension and need some advice as to what shower i should purchase for the en-suite.

I have a combi boiler and have read that a power shower is a no no.

Does anyone have any idea as to what i should be looking for to purchase here? I have read that i need one which is called a Thermostatic Mixer Shower, is this what i should be looking for?

Any advice greatly received.

Thanks

Lee

 

[g20]

What KW combi do you have out of interest.
An you will either need a high pressure mixer shower, or a decent electric shower.

Modern combi boilers supplying a mixer shower can be extremely powerful and decent showers. Far better than any electric shower you can buy imo.

 

[leevis]

The boiler itself is a Baxi Instant 105HE which i believe is 24KW. Is that any good?

 

[leevis]

Actually i think it is 31kW

 

[Agile]

I always take the view that with a modern combi you dont need a thermostatic mixer as they can sometimes interact with the combi temperature control.

I do agree that many do work alright though but I just get called to those that dont! In any case they are more expensive and less reliable.

Your combi will only supply one hot water outlet at a time.

Tony

 

[leevis]

Any recommedations as to what i should be looking for here?

Also, on that one outlet at a time, does that mean that if i was having a shower there would be no hot water anywhere else in the house until i stop? Is this going to be one of those "if someone turns a tap on while i am in the shower it gets cold/hot" things? If so, is there anyway around this?

I currently use the bath and havent ever noticed any major probs apart from pressure being a bit low when dishwasher/taps being run when i running the bath.

Just a bit concerned that its going to dribble out of whatever shower i get (once i know which type to get).

Thanks
Lee

 

[Agile]

Any recommedations as to what i should be looking for here?

Also, on that one outlet at a time, does that mean that if i was having a shower there would be no hot water anywhere else in the house until i stop?

I currently use the bath and havent ever noticed any major probs apart from pressure being a bit low when dishwasher/taps being run when i running the bath.

Thanks
Lee

With a shower you notice any fluctuations in hot water flow. Thats not noticed when filling a bath!

If this is in the loft then all other hot taps will be lower down and can easily result in nothing coming out in your loft.

A diswasher or WMC can be put on a timer to inhibit it until after you have gone to bed ( and use of peak electricity if you have that kind of account. ).

A better solution is to have an unvented hot water system heated by your existing boiler. Thats good as long as the mains water can give an adequate flow rate.

Tony

 

[leevis]

Hmmm never even heard of unvented hot water system. I was kinda under the impression that i would just need to buy the right 'type' of shower but from what i am hearing, any shower will not work properly unless nothing else is on in the house ie taps, washing machine, dishwasher, heating etc.
Is that what we are saying here?
Done a bit of a look on unvented hot water systems and they look rather high maintenance.

 

[g20]

you'd have to pay a fair whack to get your house an unvented hot water system (however it is a very good option if your not on a budget)

Mixer showers generally work fine from combi's depending on the water pressure/combi of course. I just been to a house where a Vokera Unica 32he was running 2 mixer showers. ( I Turned them both on at the same time out of interest and both showers worked fine, nice constant temperature and very powerfull too.)

 

[leevis]

Is there any way that i can find out what would work up in the loft? The reason i ask is that i dont want to install something only to find out that it isnt sufficient.

 

[g20]

If you've got a decent cold mains pressure, and dont want to fork out a load for a pressurised hot water system, then i'd put a mixer shower up there running from your combi. Or an electric shower (however i personally dont rate electric showers)

 

[leevis]

Would that be a thermostatic mixer shower?

 

[g20]

sure would.

 

[leevis]

This is probably gonna sound like a really stupid question but how are these things powered? I assume they need to be connected up to the mains or something (i really have not idea).
I am getting an electrician in this week and need to state whether i need power to this thing.
Silly question i think, but i not sure whether it yes or no

 

[g20]

2 connections, One for the cold water one for the hot water
cold comes from mains, hot is fed through the boiler.

If you decide to go for an electric shower you'll need your sparky to put in a big fat cable, no electrics for mixer showers though.

Shouldn't your plumber be sorting out the shower though?