Which shower based on these factors?

Jay8

Hi

Okay so I am having a new combi boiler installed to replace my old tank system...unfortunately my current shower isn\\\'t compatible. As for water pressure:

1. My kitchen which is above the tank has fantastic cold pressure but poor hot pressure (why do they vary??)
2. In my bathroom which is below the tank the cold is a bit stronger than the hot pressure but by no means as much as it is in the kitchen (any reason??)
3. My combi boiler is going to be the British Gas 532 High efficiency boiler

So with this in mind and wanting the most powerful shower...am I correct to assume:

a) A mixer shower is my best bet?
b) Looking at the B&Q site the Mira Combiforce 415 EV has a power rating of 12 yet the best alternative one is 7...how do mixers vary in power if they are run off the mains??? and is it worth the expense of going for something like the combiforce or from the Mira discovery range which is cheaper but has a lower power rating

Thanks in advance,

Confused in Brixton

bernardgreen

Jay8 wrote:

Hi
1. My kitchen which is above the tank has fantastic cold pressure but poor hot pressure (why do they vary??)

The cold is the pressure of the incoming mains supply
The hot is the pressure due to the height of the cold water tank which feeds the hot water tank

Quote:

2. In my bathroom which is below the tank the cold is a bit stronger than the hot pressure but by no means as much as it is in the kitchen (any reason??)

The hot and cold are pressured by the height of the cold tank. The hot has further to flow via the hot tank and pressure is lost along that route.

Quote:

3. My combi boiler is going to be the British Gas 532 High efficiency boiler

Why did you opt for a combi.

Quote:

So with this in mind and wanting the most powerful shower...am I correct to assume:

Make no assumptions. The power of the shower is determined by how much hot water the combi can supply to the shower. Increase the flow of hot water and the temperature of the hot water will drop. Turn on a hot tap elsewhere and the temeprature in the shower will drop.

The shower from a hot water tank can take as much or as little hot water without the temperature changing ( until the tank runs out of hot water ).

__________________
Bernard
Sharnbrook

Problem solver, alternate thinker, Agony aunt with a tool box

Jay8 · Posted: Sat Mar 17, 2007 1:10 pm Post Subject:

Why a combi? Because I need a new system and British Gas probably did a sales job on me telling me it was the best for my needs and the most economical. I have a few more questions based on your response:
1) So British Gas told me my current thermostatic power shower isn't compatible with the combi boiler....naieve question I am sure but what would my current shower be running off...if it's the mains would it even need to go through the combi and therefore be no need for a new shower (the one I have is a beast!).
2) What is the difference between a mixer shower and an electric shower? With a new combi boiler and the flow rates I've already mentioned...which type would be the best given the desire for a powerful shower above all else i.e. energy efficiency?

Thanks,

J.

bernardgreen · Posted: Sat Mar 17, 2007 1:59 pm Post Subject:

Jay8 wrote:

Why a combi? Because I need a new system and British Gas probably did a sales job on me telling me it was the best for my needs and the most economical.

And is least work for them to install.

Quote:

naieve question I am sure but what would my current shower be running off...if it's the mains would it even need to go through the combi and therefore be no need for a new shower (the one I have is a beast!).

If you have a hot water tank then the shower will be taking hot water for that tank and cold water from the cold tank. Both are at about the same pressure which is determined by the height of the cold water tanks above the shower.

Quote:

2) What is the difference between a mixer shower and an electric shower?

A mixer shower mixes hot and cold water, normally from tanks, to obtain the temperature you want and can be controlled to take as much or as little water as you want. The tank is heated by the boiler before you run the shower.

An electric shower takes only cold water and uses an electric heater to heat is as it flows through the shower unit.

Quote:

With a new combi boiler and the flow rates I've already mentioned...which type would be the best given the desire for a powerful shower above all else i.e. energy efficiency?

As I said the combi has no tank of hot water and you have to accept that there is therefore a fixed amount of heat ( some combis vary a bit ) going into the water. More water flow means cooler water, less water flow means hotter water. With a tank of hot water the flow rate doesn't affect the temperature.

Combis are the last option if there is space for a cold water tank in the loft and a hot water tank in the house. But first choice for ease of installation. But the installer doesn't have to live with it.

JohnD · Posted: Sat Mar 17, 2007 2:09 pm Post Subject:

I agree with all that. looking at your other post about choice of showers, it is worth mentioning that if I was having a new boiler, I would get another System Boiler and keep my cold water tank and hot cylinder. In your case you could keep your old shower too.

I am not a plumber or heating engineer so there may be some reason why a combi is best for you, but it may be worth getting some quotes for a system boiler. Be aware that it might have been recommended because it suits the installer, not because it suits you. Some people say that combis go wrong more often.

BTW BG are usually the most expensive suppliers, though they do give a dependable warranty and service and you can be confident they won't go bust or run off with your money.

Jay8 · Posted: Sat Mar 17, 2007 4:50 pm Post Subject:

It looks like I am stuck with my combi as that's what I have signed for....is there anyway of telling them not to take out the hot water cylinder and having the existing shower on the same set up and using the combi for the heating only?

Space isn't an issue but I'm wondering about whether this is advisable or whether I should just accept the combi and hope that the pressure for a new mixer shower cuts the mustard?

JohnD · Posted: Sat Mar 17, 2007 5:07 pm Post Subject:

Best to phone and ask. But see if you can get more opinions.

gas4you · Posted: Sat Mar 17, 2007 5:49 pm Post Subject:

If you can affird BG prices then you can have whatever you want

Can't see why you can't change your mind unless the boiler etc has already been purchased, which I doubt very much. Try them and see