combi-boiler or multipoint gas heater?

10 Aug 2009
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United Kingdom
We have recently had gas installed and want to replace our hot water cylinder and immersion heater with a gas fired hot water system. Our existing central heating is by electric storage radiator and we are keeping that as it is. The boiler would therefore be for hot water only.

We have obtained quotes from two reputable companies. The first one said that a combi-boiler would be fine for hot water only, as long as they fit a small radiator below the boiler (in the porch) to cater for the central heating circuit.

The second company though, said that any make of combi-boiler would need several radiators connected to the central heating circuit, as otherwise it might fail within 2 or 3 years, and any extended warranty would be void. This company recommended we have a multipoint gas water heater instead, even though the hot water output would not equal that from a combi-boiler.

Who is right?
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Provided it's installed and configured correctly, you could have a combi with a single radiator.

However you must be totally insane to have gas installed and only use it to heat your hot water.
You can have any flow rate from a water heater what you could get from a combi and more if you wanted(provided the cold flow was adequate).
You can install an intergas combi and use it as a water heater and install the heating at a later date if you want
Thanks Flameport, I`m just concerned that two reputable "gas safe" companies can have such conflicting views.
Regarding central heating, we want a combi, so that we can possibly have central heating installed in the future. The problem with installing it is that the downstairs floors are solid, so all pipework would have to be routed under the bedroom floors and down the walls to the ground floor radiators. It would involve major disruption.
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Atmos InterCombi HE32 or Intergas HRE combis can be used as water heaters without any heating system attached. Your second company are talking twaddle.

Just like Micky said (sorry dude missed you post).
If the two companies that have been out cant give u the correct advice, find someone else. Micky & Dan are correct. Any biothermic boiler can be a water heater in minutes. A Intergas is one in a microsecond!
Just thought I'd come over for a shuftie. Seen enough - time to rush back :LOL: :LOL:
I agree that the second company are talking twaddle, I think they are pushing us to have radiators installed, so that`s more work for them.

The first company gave us a suggested range of boilers in their quote, they are...
Worcester 28 Junior.
Worcester 30 CDI.
Vaillant Pro 28.
Vaillant Ecotec Plus 831.
Ravenheat Low Nox 150.(42KW)
Ideal Logic Plus 35.

The last two have a 5 year warranty, but from what I`ve read they are less reliable than the others, so they probably need a long warranty.
My advice, if you cant afford the rad central heating yet, is to save your money for a while, until you can get it all done in one fell swoop. all in all it will be less disprution to have it done in one hit, and because you wont be paying them to keep coming back, the cost would be lower.
There used to be a 400 pound grant payment to anyone changing from an electric heating system to gas!

I agree with Gasvinda that a combi setup is the easiest solution but it can be fitted with just one rad at first and add others as you can afford them.

Which is the best boiler from the list I gave in an earlier post?
I`m really not interested in the Ravenheat or Ideal Logic boilers, given what I have read about them.
I want a reliable boiler, so I would prefer a Worcester or Vaillant.
Would a 27.1KW (Worcester 28 Jun) produce enough hot water for a decent shower, or would I be better with the Worcester 30CDI or the Vaillant EcotecPlus 831?
I wouldn`t consider the Vaillant Pro 28 as it`s only got a 1 year warranty.

Even though the Ravenheat and Ideal boilers have 5 year warranties, we could still have constant problems with them, with no hot water, while we wait for an engineer to call.
well you can lead a horse to water :LOL:?

Either will be boringly fine if fitted properly.
I presume you mean Ravenheat or Ideal are just as good as Worcester or Vaillant. There are plenty of reviews on the internet that say Ravenheat (especially) and Ideal boilers are unreliable. So perhaps they are difficult to fit properly.
So perhaps they are difficult to fit properly.

No prroblem fitting both the Ravenheap and the Ideal into a skip! ;)

Seriously, either the Ecotec or WB 30CDi would be preferred choice. I would be leaning towards the Eco, personally.

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