Boiler Replacement - Regulations....!

13 Apr 2007
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United Kingdom
Hi All - Due to a cracked Heat Exchanger I am having to consider a boiler replacement :(

My house is a reasonably large detached 1930s construction with a 1970s single storey extension. My boiler is currently a Baxi Solo 2 80 PF and it supplies a total of 13 double radiators (including two 1200mm doubles) and a standard vented HW cylinder for the water. The house was extensively replumbed about 15 years ago to accomodate full CH. The boiler is located in the roof space of the extension right at the gable end wall and is vented directly through an 18" flue.

My concern is that I will be be forced into extensive replumbing to accomodate a combi boiler when all I really want is a simple replacement boiler that utilised the existing pipework as far as possible (including a 15mm gas feed) - Will the part L regulations allow me to do this? (There is no other space available in the house)

and what replacement boiler would you all recommend?

Does anybody work in the Corby area that fancies giving me a quote?

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I can't see why you would need to have any major replumbing done if you go for a heat only boiler. Your TRVs, cylinder insulation and controls may have to be reviewed but it will be in your interest in the end.... Your gas supply will have to be upgraded, I'm sorry, there is no way round that.. If you have a large house with numerous bathrooms, then I would never recommend a combi as you would have limited DHW... Even if they fitted a monster combi..
Thanks - No problem with the gas pipe really. The house has two bathrooms.

Any recommendations for a boiler? Does 30kw seem OK?
Latest baxi soloHE is a perfectly good boiler so is the vaillant 428 which would both do you ok.
Big 1930`s house ... down the park?
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First off fitting a new heat ex. isnt hard on a solo, so bear that in mind.

But money wise your probly better off fitting a new efficient boiler & changing your current cylinder for an unvented low heat loss cylinder (pressure allowing), sealing off the vent/cold feed pipes and making it a sealed system.
Just remember its is EXTREMElEY important to flush the system and add inhibitor, and also fit a filter like a magnaclean twintech on the boiler return.
I've seen countless boiler swaps go tits up after a year cos the pipework hasnt been flushed properly, all the **** gets into the boiler and fooks that aswell.
So unless u wanna be forkin out for numerous repairs for years to come ensure all existing pipework/rads is flushed out & treated, and fit a filter on the return to protect the boiler.
A properly installed and inhibited system will not create any crude .Magna cleans are the latest excuse for making more money out of customers .
Unvented cylinder will require you to have your cold mains to the house up graded and even if you did not it would still add up to a grand on to the job.
You are happy with what you have got so do not be bamboozled into thinking you need to spend an additional amount.
If you have an old unlagged cylinder then yes consider changing it to a lagged fast recovery normal cylinder but if your cylinder is not that old why bother.

Very easy to make what is done as standard on a change over sound like rocket science to get more money out of people.

You will get good honest advice from the number i have gave you and if you do get other quotes say who they are and i will advise you one way or another as i know quite a few guys around that area
to say that magnacleans(usin spirotechs now) are a swizz tells me your likely an older engineer. Unless hes gonna completely replace all rads/carcass theres a good chance sludge will be a problem, if you look at the science behind it, sludge creates sludge & hydrogen as a by-product, a system filter protects your main investment(boiler), iv seen pinholed HEX on 2yr old boilers that have been powerflushed. Even a serious all day powerflush only removes about 90% of magnatite.
As for a cylinder, a new fast recovery cylinder heats much, much faster due to increased insulation & a larger coil(calorifier), and can leave you the option to add solar panels at a later date.
Not to mention the increased flow rate, this could also be retrofitted years after the boiler swap.

Can't understand you cticism re fitting a Magnaclean, saying it is a money-making excuse. Anything that filters out foreign bodies from a ch system has to be good.

If spending a thousand or two on new boiler, cylinder, controls, etc, etc, why not spend the extra £100 and protect your investment?

Just not with a Magnaclean. Far too leak-prone. Spirotech Magnabooster2 much better.
the guy just wants a replacement boiler. Why are you babbling on about unventeds and solar etc?? Profiteering is what I call that.
Upgraded gas main i heard too?? He's got an 24kw boiler? presuming it was installed correctly with a correctly sized pipe then it won't need any alteration, thats for the man on site to decide not us , on a forum looking at a screen ! Simple boiler change, 24 kw just like the old one , maybe a powerflush, but that depends on water quality, again, man on the job, leave it to him! Nothing wrong with fitting magnacleans(other products are available!) but not a necessity on a properly installed and clean system that gets reliable maintenance.
Plenty of good heat only boilers about, again, have this conversation with your installer, he'll no doubt be familiar with certain products.
Any recommendations for a boiler? Does 30kw seem OK?

You can easily work out yourself what size boiler you need if it is heat only.

1. Measure all your radiators.
2. Add up the lengths. 1 metre = 1 kW for single and 2 kW for double at 600 mm height.
3. Add any increase that may be needed, including any upgrades or extensions you are considering.
4. The total of 2 and 3 is the amount required, so you choose the smallest model of your preferred choice that can accommodate that number.
he might just mean 15mm at the boiler.. depends how you read it i guess.

I read it with my experience of old boilers in mind ( no pun intended ). How many boilers do find with a drop of less than 1mb?

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