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10 rads on one 15mm feed!

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Recently got started on the plumbing side of our project Victorian house and realised something daft about the heating system. It is working so wasn't a priority but wasn't doing a great job overall which I guessed could have been the elderly boiler, sludge or not great old radiators. It has 22mm for about a meter then tees to 15mm's one going upstairs and the other going to the kitchen and onward downstairs. Thing is the one going up only feeds one radiator above in a separate lower back section of the house while the other 15mm splits again to go up and down for the rest of the house and feeds 9 radiators plus an indirect heating coil in a fair sized storage tank so lets call it 10 rads in total. Is that some kind of record?

To be fair it does heat the house enough just about despite sash windows I think because its a very sheltered location wind wise, but the stupid thing is the main riser is at the other end of the same room only 5 meters away from the individual rad so I can just run a couple of pipes and make it 5 and 5 (storage tank is going). What kind of country plumber thought 10/1 was a fair ratio?

Apart from that there doesn't seem to be any sludge in the system, the boiler is non-condensing, has zero rust as its non-condensing, zero plastic, zero fancy electronics, is all brass and literally every part that might go wrong is available on ebay for 10% of shop price I guess because heating engineers just say "get a new one mate" to everyone. A guy who looked at this said by law he can't buy genuine parts on ebay for 10% of city plumbing prices but can fit them if i do. I can't find that law. Attic is now full of new old stock spares. Flue gas efficiency is reading 93% on high burn and its all spotless inside. He still said "I'd get a new one mate, give me a couple of thousand, no worries mate you know it makes sense" The government will have to pry this thing out of my cold dead hands if they tell me I've got to swap it for a condensing one that is barely any more efficient and needs replacing every 10 years or a heat source pump
 
Flue gas efficiency is reading 93% on high burn
Sorry but this doesn't really mean anything

As far as heating 10 rads off of 15mm then would all depend on rad sizes, heat loss etc but not impossible though would need some very tight balancing to get enough heat to them all. On average a 15mm pipe will carry around 4Kw @ a 1.5m/s flow rate.

As far as parts are concerned then if you have found a GSR engineer that will replace parts with stuff you 'have in the attic' then you're doing well.
A guy who looked at this said by law he can't buy genuine parts on ebay for 10% of city plumbing prices
Really ... wonder why he said that, if I could get genuine parts on ebay for 10% of list prices then I'd be fitting them and my clients would love me. Certainly isn't against the law. More likely they won't be genuine.
heating engineers just say "get a new one mate" to everyone
Unfortunately a lot do but not everyone - I look after 1 Baxi Bermuda and 2 Kingfisher 2's and will do until they need certain parts that can't be obtained any more.
 
Sorry but this doesn't really mean anything
I realise its not the whole story for boiler efficiency overall but what does it mean if not related to that? One thing i do understand about efficiency is that replacing a boiler more often due to condensing having shorter life, more expensive parts, more complicated to fix etc should be taken into the equation. This older boiler housing seems unaffected by time and the internals are currently cheap
More likely they won't be genuine.
some are sealed genuine boxes from spares shops who I guess are clearing out their selves as very few people are fixing them. I ordered a few small parts which weren't on ebay to make sure I didn't have everything except one silly thing and I've got to say I'm impressed with the manufacturer still supporting a 20+ year old boiler. But i'm assuming that wont last forever so grabbing it now while I can
Unfortunately a lot do but not everyone - I look after 1 Baxi Bermuda and 2 Kingfisher 2's and will do until they need certain parts that can't be obtained any more.
I had a couple say it, didnt bother looking at it - old boiler - get a new one. I realise not all though, didn't mean to say everyone. That said I can see why its often the best idea looking at the price of some new parts and considering if one part is wearing out the rest might not be far behind, but when they are available new old stock it starts to make sense to repair.
As far as parts are concerned then if you have found a GSR engineer that will replace parts with stuff you 'have in the attic' then you're doing well.
You make my attic sound more sordid than it is. I'm talking about original manufacturer parts in their boxes just transferred from a dusty back corner of a dealers store, where they might end up in a skip if i dont buy them, to my less dusty attic for safe keeping. I think i'm at the sweet spot in time as I notice slightly newer boilers parts aren't as cheap but this one is on the cusp of dealers just binning them so its give away prices. New sealed Honeywell gas valve for £20, new burner for £35, new brass diverter valve for £35 (just under £400 at city plumbing), genuine DV service kits £7.50, genuine OEM plate exchangers for £20, new PCB £25. I've added a magnaclean to the system and will make sure its all annually serviced. Hoping to get another 20 years out of it
 
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I realise its not the whole story for boiler efficiency overall but what does it mean if not related to that?
An old non condensing boiler will be no where near 93% efficient, the fact that all modern boilers are now required to be condensing is where their increase from standard efficiencies up to efficiency rates of >90% comes from.

If you have got genuine parts that are cheap then great and if you have a GSR engineer that is happy to fit them then even better. As far as the comment about the attic then I certainly didn't mean it to sound sordid.

Of course there will always be installers saying - "it's not worth repairing, just replace it", and if it can be economically repaired then unfortunately they aren't very professional and realise that unfortunately a lot of people are too trusting and will believe them. That being said other would like the peace of mind that comes with a new boiler that is warrantied (if installed properly) and will be covered for the foreseeable future.
 
That being said other would like the peace of mind that comes with a new boiler that is warrantied (if installed properly) and will be covered for the foreseeable future.
Ah yes like cars, most just want to lease it so they never have to be concerned about repairs. If they have the money thats fine but all these leases and contracts and subscriptions add up and I don't know where people get the money. If they take a hit in wages, as its going out the bank steadily and they are tied in they dont have an option to tighten their belt as it just keeps going out. On the other hand they get less surprises with an unexpected repair bill... I'm old school and always think about how to be frugal, self sufficient and staying out of debt.
 
right now i get it, 10 year warranty, peace of mind, when that is up, peace of mind has gone, first time something goes wrong its the easiest sell to say get a new boiler as it will have a new 10 year warranty. And if thats the normal way of things then thats just what engineers expect people want.

On the one hand we're bothered about efficiency for the good of the planet and on the other the unintended consequence of the way we do things encourages early replacement which has the opposite effect. I guess if 10 year replacement is the norm they will be made down to a quality that fits that as well hence more plastic and less brass
 
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A well looked after boiler can last a lot longer than 10yrs and only really needs to be replaced when it becomes uneconomical to repair.
 
A well looked after boiler can last a lot longer than 10yrs and only really needs to be replaced when it becomes uneconomical to repair.
I'm guessing you are a heating engineer? do you see people preferring to just get a new one at the first sign of trouble for the new warranty? £3000 / 120 months = £25 a month. I can see that appearing normal to many people. Just checked and sure enough you can in effect lease a boiler on finance like a car. 10 year finance presumably also make sure has 10 year warranty, steady outgoing, no risk of unexpected bills, https://www.boxt.co.uk/boilers/finance

"we'll own nothing and be happy". Its all good as long as they never step out of line or lose their job for any reason.
 
Most of my clients will make a decision on best advice given. If the boiler isn't EOL and can be looked after, regardless of age, then that would always be an option. In certain circumstances though they may look to a new boiler as an option - new house purchase etc - and they want the piece of mind of a new boiler with its warranty etc. The pros and cons of all of that would then be pointed out and again that would then be their advised decision.

It's true a new boiler will certainly take years to offset the cost against efficiencies gained but that's not always the defining factor for some. As far as financing a boiler, like all loans it will usually increase the end cost significantly but some may have to take that option as they don't have the initial capital to outlay. It is a shame and a sign of the times that such an essential item like a boiler cannot be financed @ 0% interest as it obviously penalises those that can't afford the outlay.
 
Most of my clients will make a decision on best advice given. If the boiler isn't EOL and can be looked after, regardless of age, then that would always be an option. In certain circumstances though they may look to a new boiler as an option - new house purchase etc - and they want the piece of mind of a new boiler with its warranty etc. The pros and cons of all of that would then be pointed out and again that would then be their advised decision.

It's true a new boiler will certainly take years to offset the cost against efficiencies gained but that's not always the defining factor for some. As far as financing a boiler, like all loans it will usually increase the end cost significantly but some may have to take that option as they don't have the initial capital to outlay. It is a shame and a sign of the times that such an essential item like a boiler cannot be financed @ 0% interest as it obviously penalises those that can't afford the outlay.
A new boiler can pay for itself faster when you consider not only the savings on gas, but also lower repair costs.
 
A new boiler can pay for itself faster when you consider not only the savings on gas, but also lower repair costs.
why would repair costs be lower on a newer boiler?

edit - you mean no need for repairs at all as its new? rather than the same repair would be less on a newer boiler.

One of the things I'm seeing said is the newer boilers are more complicated so more to go wrong and more expensive parts and more complicated so more time to work on. Looks like some of the plastic parts are cheaper to replace than brass though maybe need replacing more often.
 
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A new boiler can pay for itself faster when you consider not only the savings on gas, but also lower repair costs.
Potentially yes and the warranty will pay for any repairs on the new boiler, if and it's a big if, it has been installed as per the MI and it's been serviced yearly properly, which we all know a lot aren't.

That's also assuming that the old boiler will need repaired, which it may not if it's properly looked after.
 

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