which boiler

[maverick52]

Having a combi fitted , and not sure which boiler to go for, i have narrowed it down to a worceter bosch 30 ri or a baxi duo tec , is there much difference, which are the best company when it comes to a call out under warranty,

also i am not sure wether to go for a boiler with a higher hw flow rate, my mains cold water is giving 20lts per min and 4 bar pressure at the garden tap i want to fit. a mixer valve in the fist floor bathroom and want a decent flow at the shower, is there any point in fitting in fitting a boiler with more than 12ltr per min flow

 

[Hot&Cold]

want a decent flow at the shower

have fitted a few Bristan artisan bar shower mixer valves. For combination boiler use the shower has 7 litre/min flow limiters fitted in the hot&cold inlets and produces a very good controlled shower experience.

Try to avoid unknown shower mixers,some look great in the shiny internet adverts but produce trash water flow.

Got a 33kw combi where i live now,its limited to 12 litres per minute and it fills a standard bath in reasonable time and produces a very decent shower via a Mira 415 shower mixer valve.

baxi would be my choice.

 

[maverick52]

Thank you for the reply, i have had a look at the bristan, and looks just what am looking for , the fitting instructions state the flow regulators must not be removed if using on a combi, do you know why that is,
thanks

 

[durhamplumber]

"which boiler".you could have a 100 replies all saying different.from your point of view.baxi duotec is middle of the road.reliable.easy.w.bosch anything but.similair from a repair perspective.i always fit duotec.7 year part and labour.few problems.if you are a real techy dude into fancy controls..compensators..flow and return temp..delta t....then you are a w bosch chappy...if you just want some heat and water....baxi

 

[muggles]

Having a combi fitted , and not sure which boiler to go for, i have narrowed it down to a worceter bosch 30 ri or a baxi duo tec , is there much difference, which are the best company when it comes to a call out under warranty,

Are we allowed to say "neither"?

Worcester took 2.5 days to get to a dead boiler for me under warranty a couple of weeks ago, in central Oxford so not exactly out in the sticks. Fitted it under duress in the first place and now more resolved than ever not to fit another. They're full of plastic and the build quality isn't as good as the price tag would suggest. They're also a pain to work on...ofter literally with a lot of sharp edges to cut your fingers on

The DuoTec is better built, but should be supplied with complimentary ear defenders... it's got no sound insulation whatsoever and is consequently very loud at full chat (IE any time you draw hot water). Fine in a loft, wouldn't put one in a living space. Baxi are taking as long as 20 minutes to answer the phone at the moment.

Try Intergas for size. 10 year warranty, did call them out once and they were with me 3 hours, yes hours, later, bulletproof design with a heat exchanger that's suffered zero mechanical failures in 20 years, and made of good old fashioned solid brass and copper

 

[bernardgreen]

bulletproof design with a heat exchanger that's suffered zero mechanical failures in 20 years, and made of good old fashioned solid brass and copper

How many boilers come under attack from gun fire. ?

But seriously the heat exchanger is a large mass of cast aluminium and copper pipes that has to be heated before any heat reaches the water. After water stops flowing the heat exchanger cools down losing heat to the atmosphere.

Mechanical failure, something breaks
Hydraulic failure, something leaks

 

[dilalio]

How many boilers come under attack from gun fire. ?

Quite a few in certain parts of the world.

 

[muggles]

How many boilers come under attack from gun fire. ?

But seriously the heat exchanger is a large mass of cast aluminium and copper pipes that has to be heated before any heat reaches the water. After water stops flowing the heat exchanger cools down losing heat to the atmosphere.

Mechanical failure, something breaks
Hydraulic failure, something leaks

Go away, you insufferable troll. You know nothing about this

 

[bernardgreen]

Go away, you insufferable troll. You know nothing about this

Can you truthfully deny that significant heat is used to heat the mass of the heat exchanger before any heat reaches the water ?

""Quietness Whisper Performance Vacuum insulation reduces heat and energy losses"" I am told this insulation was originally fitted only to units sold in Holland and not fitted to units sold in the UK. Is that true ?

 

[bernardgreen]

Can you truthfully deny that significant heat is used to heat the mass of the heat exchanger before any heat reaches the water ?

One could assume that your lack of response confirms that significant heat is used ( a significant amount of gas burnt ) merely to heat the heat exchanger,

 

[muggles]

One could assume that your lack of response confirms that significant heat is used ( a significant amount of gas burnt ) merely to heat the heat exchanger,

One could, but one could equally assume that it's the busiest time of year, I have work to do and am working 14 hour days, and I don't come on here every day.

Of course energy is used to heat the heat exchanger, that's how a boiler works - gas is burned in close proximity to a heat exchanger, the heat generated in the combustion process warms up the heat exchanger, which transfers that heat to the water in the system.

Intergas boilers are all made in the same factory on the same production lines regardless of where they're headed. I find it highly unlikely that they'd want to have two different insulation materials which they'd have to faff around changing over between production runs. To the best of my knowledge they all get the same insulation, and the ones that come here are certainly very quiet at 50db

 

[bernardgreen]

I find it highly unlikely that they'd want to have two different insulation materials

I was given the impression it was fit or not fit. Not that there were two different types of insulation.

What happens to the heat in the mass of the heat exchanger if it is an hour before the next draw of hot water from the boiler ?

Small mass heat exchangers are more efficient.

EDIT spelling error corrected

 

[aptsys]

They're full of plastic and the build quality isn't as good as the price tag would suggest.

There's nothing inherently wrong with using plastic - in many cases you get favourable properties over the metal counterparts and would have been used 'in the olden days' had the production methods been viable.

 

[dilalio]

One could, but one could equally assume that it's the busiest time of year, I have work to do and am working 14 hour days, and I don't come on here every day.

Of course energy is used to heat the heat exchanger, that's how a boiler works - gas is burned in close proximity to a heat exchanger, the heat generated in the combustion process warms up the heat exchanger, which transfers that heat to the water in the system.

Intergas boilers are all made in the same factory on the same production lines regardless of where they're headed. I find it highly unlikely that they'd want to have two different insulation materials which they'd have to faff around changing over between production runs. To the best of my knowledge they all get the same insulation, and the ones that come here are certainly very quiet at 50db

Don’t waste you’re words Mugs... you’re on a hiding to nothing. BG would find fault in anything that appears to have a group following. I don’t inherently disagree with his anarchism but we are tradesmen and not academics and we have a desire and need to make a living and that involves finding a one size fits all approach to our business models - but on a much more personal level than as peddled by the big organisations.

 

[bernardgreen]

BG would find fault in anything that appears to have a group following.

Am I finding fault or am I pointing out that the published figures of boiler efficiency are in almost all cases figures obtained under test lab conditions using ( manufacturer's ) test protocols designed to provide the highest operating efficiency. Figures for efficiency obtained from monitoring boilers installed in domestic situations are invariably lower than those from the test lab. In some cases they are much lower, maybe a third of the efficiency in the test lab. If the test lab say they verify the manufacturer's claims then be ready for a dis-appointment.

finding a one size fits all approach to our business models

Having run my own electronics design busines for several years I agree that using a one size that fits all applications is sensible for the business owner. But it may not be sensible for the customers when the fit all size does not perform at it's best in that customer's installation and requirements.

That said there are two main types of customer. Owner occupier is one type. The other type is the landlord who rents property to tenants and has responsibility for repairs but not utility bills

In electronics the two main types are (a) owners and operators of a system and (b) service providers who own and maintain the equipment and hire it ( or a service it provides ) to their customers.

With heating and hot water the owner occupiers want reliable equipment with low running costs, they may invest in a more expensive item to get both reliability and low running costs. The landlord ( private and housing association ) wants reliable equipment that doesn't go wrong and if it does go wrong is fast and low cost to repair. The landlord is not concerned about the running costs and will therefor not be too concerned about the real life efficiency of the boiler. These are two different requirements which are unlikely to be satified by a one size fits all boiler.

we are tradesmen and not academics

Tradesmen should still be aware of the basic physics of the trade they are in and if they are going to be giving advice to potential customers about which equipment best suits their requirements and situation they should evaluate ( manufacturer's ) marketing claim using this awareness of basic physics. They should also be aware that test lab results used to sell boilers to the average man in the street are not the results that the customer will get in their own home.