And what does BS 6891-2005-A2-2008 say about the pipe?
Advice on combi boiler
- Thread starter low drains drifter
- Start date
Chav, are you the quizmaster at the local pub? Wow!
Come on .... get cracking.
Oh tell us. We give in. Tell us.
No work ity out for yourself.
You portray yourself as the font of all knowledge and reason.
Either demonstrate you actually know what you drivel on about or kindly foxtrot oscar.
You portray yourself as the font of all knowledge and reason.
Either demonstrate you actually know what you drivel on about or kindly foxtrot oscar.
UK, a 28 kW combi will most likely take care of your heating requirements unless you live in a mansion with high ceilings and rooms where a jumbo jet could be taken apart
The issue will be hot water delivery. Banging another combi in is not the answer. I suggest you keep the existing boiler, get it serviced properly ( preferably not by your builders plumber) and money you propose to spend on a new combi, invest that in an unvented cylinder (solar even)
In doing so, if the boiler does fail, you will still be able to heat water electrically
It is mental to fit a big combi.
I think I will take bets the gas line will be undersized and system will not be cleaned and system will not have boiler interlock or properly fitted condensate. Any takers?
I am sitting at Singapore airport just now. By the time I get home, let a few days go by, this job will be finished and if checks are made and I am right, I will not need to do any work for rest of the week.
The issue will be hot water delivery. Banging another combi in is not the answer. I suggest you keep the existing boiler, get it serviced properly ( preferably not by your builders plumber) and money you propose to spend on a new combi, invest that in an unvented cylinder (solar even)
In doing so, if the boiler does fail, you will still be able to heat water electrically
It is mental to fit a big combi.
I think I will take bets the gas line will be undersized and system will not be cleaned and system will not have boiler interlock or properly fitted condensate. Any takers?
I am sitting at Singapore airport just now. By the time I get home, let a few days go by, this job will be finished and if checks are made and I am right, I will not need to do any work for rest of the week.
That I am Chavvyboy. All the "plumbers" here said a U6 can't handle two combis. I proved a U6 can with lots to spare. I have nothing to prove to you. How many points do you give for answered questions?
While I am at it, I looked at two Intergas Rapids. From manual, gas consumption (G20 natural gas) is m3/h 0.74 to 3.02 for the 25kW and 0.79 to 3.39. Two 25kW is borderline just a minute tad over 6 m3/h. As a U6 has an overload of 100% I would go with it. But no gas hob.
These two give you zoned heating and the DHW outlets can be joined using check valves to supply a bath with a zestful bath fill. No large cylinders, zone valves and the likes, just two small neat white boxes on a wall. Quick to fit and ....Oh and backup if one breaks down. And much cheaper for what you get.
You should be promoting your fav combis.
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With a mass of expensive copper pipe. Feeding these boilers producing shyte turndown ratios when feeding half a house.
What about gas fires? Didn't include those did you.... what about cookers.... a free stander will easily take 16kW. My hob takes 11kW and we until recently had a fire too. So with two combi's you can easily be over the limit of the meter.
What about gas fires? Didn't include those did you.... what about cookers.... a free stander will easily take 16kW. My hob takes 11kW and we until recently had a fire too. So with two combi's you can easily be over the limit of the meter.
As unvented cylinders are dependent on the service via the cold water mains pipe I always wonders why there is this obsession with unvented cylinders I see about.
The only high pressure you really need is on a shower. I saw one combi fitted that supplied only the shower and kitchen tap. A combination cylinder was fitted with a large cold water tank section. No cold tank in the loft and I have seen these in flats as well. The combination was heated from the heating side of the combi boiler using S plan (2 zone valves). All the cold supplies were taken off the cold tank section of the cylinder with the only cold mains tap being the kitchen tap. It was all at low pressure and worked wonderfully. The only high pressure was the shower and kitchen sink. Bath fills were quick. The brass ballcock was replaced with a plastic version that delayed the fill until the water water level dropped a bit. Why installers do not adopt this method is beyond me. No pressurised water in a house which is a good thing.
The only high pressure you really need is on a shower. I saw one combi fitted that supplied only the shower and kitchen tap. A combination cylinder was fitted with a large cold water tank section. No cold tank in the loft and I have seen these in flats as well. The combination was heated from the heating side of the combi boiler using S plan (2 zone valves). All the cold supplies were taken off the cold tank section of the cylinder with the only cold mains tap being the kitchen tap. It was all at low pressure and worked wonderfully. The only high pressure was the shower and kitchen sink. Bath fills were quick. The brass ballcock was replaced with a plastic version that delayed the fill until the water water level dropped a bit. Why installers do not adopt this method is beyond me. No pressurised water in a house which is a good thing.
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Chavvyboy, read what I wrote. Only the two Intergas Rapids. Will you explain to us what your "turndown ratios" are please. You can use cheaper plastic pipe. NO expensive zone valves or cylinders taking space and adding complexity and cost. A heating and DHW backup in the house if one drops out (rare we know, but it happens).
You should be promoting your fav combis to give a fantastic service to the customer. Much cheaper to buy all the kit and also to install. Much quicker to install.
Google turndown ratios. 
What happens if they have a diverting shower/bath filler moron?
Mine for example. Push button 1 it fills a bath.
Push button two, it runs a shower.
Push buttons 1 and 2, it runs both.
What happens if they have a diverting shower/bath filler moron?
Mine for example. Push button 1 it fills a bath.
Push button two, it runs a shower.
Push buttons 1 and 2, it runs both.
.
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