Which Boiler?

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markjay

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Boiler buying time... :)

I think I'll stick to Vaillant, this is what we have now and it seems lime a good brand.

Looks like we will change the system from the current separate boiler and (gravity-fed) tank to a combo - to save the space taken by the tank.

So probably Vaillant EchTec or EcoTec Plus (no idea what's the difference).

We have three showers so have been advised to opt for 37-40Kw system.

How am I doing so far? Any comments/suggestions?

Also, not related, but has anyone heard of a British-made(?) Boiler called Atmos Intercombi HE32?


Help and advice appreciated.
 
I forget which specific EcoTec model it is, but you can combine it with a matching Vaillant air-source heat pump.

The latter does the heating until the really bitter weather bites, which is when the conventional boiler takes on the strain.
 
If you are going to possibly have all 3 showers going at the same time then unless you have a very good mains water supply then IMHO (I am not a plumber) you will not have enough water pressure to keep all 3 going at the same time. If however you are able to stagger when the showers are in use, then I would go for a Worcester Bosch 30CDi or larger depending on the size of your home. Worcester Bosch have a very good reputation and are a "Which" best buy.
 
Hello

Having just moved house and had a full renovatiob going on,..... new boiler, rads, pipework etc.

I went for the same as my dads :)

Worcester Bosch 440Cdi, floor standing sort of dish washer sized. It connects to an RF controller in the house and so far so good.

I was advised to get an electric shower and a power shower in case of any issues though (athough 5 year warranty).

This model is great than I need but we also over did the rads so if we needed 2kw in a room I put in a 3kw (you can always turn it down) my wife likes the house warm !

The boiler and RF transmitter was around £2K (plus fitting etc) Must be good it sounds like a Merc engine 440Cdi :)
 
I forget which specific EcoTec model it is, but you can combine it with a matching Vaillant air-source heat pump.

The latter does the heating until the really bitter weather bites, which is when the conventional boiler takes on the strain.

'...Vaillant air-source heat pump. The latter does the heating until the really bitter weather bites...'

Hmm... interesting - how does it do that?
 
If you are going to possibly have all 3 showers going at the same time then unless you have a very good mains water supply then IMHO (I am not a plumber) you will not have enough water pressure to keep all 3 going at the same time. If however you are able to stagger when the showers are in use, then I would go for a Worcester Bosch 30CDi or larger depending on the size of your home. Worcester Bosch have a very good reputation and are a "Which" best buy.

We have applied to the 'Water Board' (or whatever they are called today...) for new supply i.e. larger pipe from mains - so far they approved 32 but we are pushing for 50.
 
Hello

Having just moved house and had a full renovatiob going on,..... new boiler, rads, pipework etc.

I went for the same as my dads :)

Worcester Bosch 440Cdi, floor standing sort of dish washer sized. It connects to an RF controller in the house and so far so good.

I was advised to get an electric shower and a power shower in case of any issues though (athough 5 year warranty).

This model is great than I need but we also over did the rads so if we needed 2kw in a room I put in a 3kw (you can always turn it down) my wife likes the house warm !

The boiler and RF transmitter was around £2K (plus fitting etc) Must be good it sounds like a Merc engine 440Cdi :)


Thanks - is it a Combi?
 
Yes and I think it has a built in tank also?
 
I had an 838 Ecotec Exclusive fitted in January and the house has never felt so warm, would thoroughly recommend it. They also do a similar model that has a small hot water tank inside that may be better with three showers. IIRC I think I paid just under £1300 but the flue, timer and room stat were extra
 
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Combi is more complicated - more to go wrong

A separate hot water tank can be a good back up to have, as you can heat water by an immersion heater, if boiler breaks down.

An airing cupboard is useful for clothes, so if new boiler not in there, where/how do you plan to air clothes ?
 
Vailliant seem to be recommended by plumbers I deal with.
Look at "flow rates" for the combi boilers.
To get a reasonable shower you need a flow rate around 13 - 15 litres/minute. If all 3 of your showers are running at once then you need 40 - 45 litres per minute output.

You are going the right way with increasing your supply pipe, 32mm may be adequate (internal bore is actually 25mm). Bear in mind that you can bring that diameter of pipe to the house, but to get the benefit you will need to increase all of your internal pipework sizes.

Water pressure & water flow rates are different. Whilst you need good pressure, more important is the flow rate.

I doubt you will find a gas combi boiler with a flow rate of 40 litres/minute.

We have 3 showers, but only moved in a couple of months ago & don't know that we have had all 3 running at the same time.

We put in a new 32mm water main, converting to 28mm copper in the house. This is then reduced to 22mm.
Mains pressure is over 6 bar so we have had to fit a pressure reducing valve to reduce the pressure to 3.5 bar (water softener seals can't handle over 5 bar).
We have a 300 litre unvented hot water cylinder, heated by an air source heat pump. This gives "mains pressure" hot water. The take off from the cylinder is 28mm, split into 2 x 22mm, one feeding the main bathroom, the other feeding the 2 ensuites, kitchen & utility.
We also have a 240 litre accumulator (presurised cold water cylinder). This stores approx 120 litres of cold water at mains pressure. In the ideal world this would be a larger cylinder, but it is one I already owned. When a tap is opened, it draws from the mains & the accumulator at the same time. This is like having a larger bore mains.
 
Thanks - can you please elaborate.....

Basically what kth286 has said- less to go wrong- lots of people seem to have problems with the pressurising aspect of these systems after a few years whereas with a header tank/vented system there's virtually zero to go wrong. With Combi boilers hot water total demand capacity can sometimes be a problem and as already said a hot water tank is a nice reserve and a secondary hot water heating system with an immersion element should your boiler go awol for any reason.Unless space is at a premium that's the way I would go.
 

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