New boiler recommendation

[RickH]

I have a house heated by Underfloor Heating .. and the source is a Baxi Barcelona (set to 29KW), pumped primaries go direct to a pressurised Thermal Store.
Control to the boiler is simple - 240VAC supply when Thermal store calls for heat, boiler burn, modulation as it decides.
No timer or control on the Bolier other than the built-in 'temperature dial'

It's now close to 20 yrs old .. and of late has been unreliable ... loads of cct boards, burner door, electrodes, burner, fan, heat exchanger, flue all been changed - some several times.

Time to look for a replacement ... welcome suggestions for a condensing heat-only boiler, wall mount, 30KW.

Tried Googling and the common choices are in order:
Vaillant EcoTec
Viessman Vitodens
Worcester Greenstar RI

Anybody anything against these or alternate choice.

 

[ChloeRadshaw1]

This question should be a sticky. Me and my colleague at work both independently came to this forum looking forward this famous answer. What is the best combi boiler.

for what it’s worth I picked the vies mans in the end.

 

[MeldrewsMate]

Just like buying a car, buy one made in the UK and keep the jobs in this country.

Specifically, look at ways of increasing your insulation, then do a re-calculation of your heat losses. You may find a 24kW boiler will suffice, will cost you less, and be cheaper to run.

 

[whall3y]

for what it’s worth I picked the vies mans in the end.

No, you should have picked a Worcester Bosch
No, you should have picked a Baxi
No, you should have picked a Vokera
No, you should have picked an Intergas
blah, blah, blah

... ask 5 Plumbers/Heating Engineers and you will get 8 different answers as to the best boiler as you have found out.

 

[dilalio]

... ask 5 Plumbers/Heating Engineers and you will get 8 different answers

Ask "anyone" and you'll get the same.

 

[ChloeRadshaw1]

Shouldn’t be hard or controversial. Take cars as example above. People know rolls Royce best but expensive to service. BMW Mercedes are well wade reliable etc. Vauxhall budget entry cars.

 

[dilalio]

I picked the vies mans in the end.

Tell us your top 5 reasons (in order) for picking it?

 

[muggles]

Look at the Intergas ECO RF - set up as a system boiler in the parameters, it'll give you excellent reliability from a very solid well-proven design., and a 12 year warranty when fitted with the Intergas system filter.

Thermal stores aren't a great option for modern condensing boilers (of whatever flavour) as they usually run too hot. Condensing boilers will only condense properly when the difference between flow & return temperature is kept at 20°C and the return temperature is at 52°C or below. Thermal stores often run at 80-85°C, and to maintain that temperature your condensing boiler ends up reverting to standard efficiency.

It's therefore worth considering doing away with the thermal store and putting an unvented cylinder in instead. Coupled to a boiler capable of producing a consistently low flow temperature for your heating, and a higher one to heat your hot water, such as the one I've suggested it'll make the most of your upgrade to a modern boiler. Hope that helps

 

[RickH]

I do not want a system boiler, only a Heat only boiler.

I cannot do away with the thermal store it is integral to the Undefloor Heating design, providing mains pressure DHW as well as low temp Heating.

I know Intergas often mentioned here, I have asked several SSE gas engineers (service calls) non of them have come across or heard of this make.
May mean difficulty getting it under maintenance contract, though not tried.

 

[muggles]

Fair enough, you'll find the warranties are generally shorter on a heat only boiler though, and there's often no reason not to have a system boiler - you simply remove the existing external pump and make use of the one inside the system boiler instead, which is then covered by the warranty. Intergas make an OV boiler though, which is heat only if that's what you prefer.

I've converted many systems such as yours from a thermal store to an unvented cylinder, to split off the UFH to run directly off the boiler and run the hot water from the unvented cylinder instead. The thermal store may have been integral to the original design, but that doesn't mean it's the only available design, and with modern boilers it's an inferior setup as it ruins the boiler's efficiency.

You won't need a maintenance contract with a new boiler. It's covered by the manufacturers warranty. A maintenance contract means you're paying twice for the same thing. Just pay a trusted local installer (or even the manufacturers themselves) to service it annually and that's all that's required. I'd say it's a good thing that your SSE engineers haven't come across Intergas boilers - it means they aren't being called out to fix them.

 

[sxturbo]

Follow muggles advice.

at the end of the day it doesn't matter which boiler you choice as they all have long warranties, all have dedicated service teams. The warranty is your maintenance contract, so save your money.

 

[RickH]

The Thermal store is an integral part of UFH design, it cost a lot of money and it works well - nothing wrong with it so don't need or want to change - also there would be no benefit to doing so. The UFH should not be run direct off the boiler .... this is low temp heating, and running boiler at that low a temp would be inefficient.
Far better to have long full efficient burn and store the heat .... then use that at low temp as required.

It wasn't just SSE not heard of Intergas, just had an indepeneadnt Heat engineer at a propery I rent out, he had never come across Intergas.
I don't dubt technology of Intergas may be good .... but they are not widespread, and when I checked no local suppliers (nearest is in Newtown) and nearest approved installer is 150 mile round trip ...... so unfortunatley they do not have enough coverage.
I would probably find that maintenece contract may be an issue - companies don't like non-mainstream boilers ..... as their engineers are not traioned on them, unfamilair and don't carry spares.

I know you mentioned - don't need a contract - I do as whole central heating needs to be coverred not just boiler, and the gas hob.

A pity as having looked at the webiste the technology of some parts is good.

 

[Londoner2]

Shouldn’t be hard or controversial. Take cars as example above. People know rolls Royce best but expensive to service. BMW Mercedes are well wade reliable etc. Vauxhall budget entry cars.

Or BMW/MERC = decline in quality
Vauxhall = if its not good enough for Clarkson, its not good enough for me.

 

[ianmcd]

I'd say it's a good thing that your SSE engineers haven't come across Intergas boilers - it means they aren't being called out to fix them

They wouldnt be able to , they are mostly absolutely useless, company policy was to recruit newly qualified and teach them to work the company way, which is Poke and go servicing, havent a clue when it comes to repairs, was surprised they took so long to go down the tubes

 

[RickH]

I just checked again on Intergas site for their Heat only boilers it states "The Intergas Compact HRE OV open vent boiler is a central heating-only boiler to be used in an open vented system with a header tank."

The heating design is to a pressurised Thermal store with correctly sized expansion vessel on pumped primaries ..... it is not an open vent design.