kinked, crimped and coiled 8mm pipework

[ShaunCorbs]

The worst case I have is 4 rads off one 22mm branch, medium sized k1's. And one 800x400 towel rad.

Would I be good reducing to 15mm with a straight push fit, then a series of 3 15mm T's immediately after to save cost. Or would you recommend a series of 22mm reducing T's in line

Edit: I'll try and upload my drawings of the upstairs pipe run later, to give bit more perspective

22mm ts

 

[1animal1]

Cheers Shaun, much appreciated :coffee:

I gather it won't make much difference to the flow if I use the end of the last T for the fourth feed, or should I cap this

 

[jtsplumbing]

What could be of use to you and would answer a lot of your questions, Go on to CORGI web site . & purchase a copy of ( Wet Central Heating System Design Guide.)

 

[1animal1]

Thanks for the suggestion JTS, isn't that a bit overkill though given the fact that I'm making some minor adjustments to an already installed system and asking some relatively basic questions.

I thought I'd use a forum to gain a bit of advice which is what it's here for is it not?

 

[jtsplumbing]

No it has some good illustrations and is easy to understand, even covers unvented systems just thought it may help you understand how different systems work, Think it gets handed out to guys doing plumbing & Heating course. used to get a heat loss CD so that you can work out rad sizes.

 

[1animal1]

Ahh OK, I'll have a look at that... Thanks for the heads up

 

[ShaunCorbs]

http://bpec.org.uk/downloads/CE30 - Domestic heating by gas.pdf

 

[jtsplumbing]

There you go, even better its free :book: thanks to Shaun

 

[1animal1]

Extremely useful read... Thanks chaps. I have done a bit of independent reading too on star systems and the benefits of single pipe loops, feed and return and microbore systems prior to settling on the unvented. My plumbers initial advice was a large combi, but the need for high pressure hot water to the en suite, maybe eventually the main bathroom and possibly a second en suite if I get around to building it - he agreed that the unvented was the way to go.

One thing that was a concern was the suggestion that a feed and return system can handle roughly up to 12 rads, where I have 13. This is why I'm thinking of extending the feed so that it can be accessed by the new boiler more directly, than having to access the feed through the old pipework, running 7 metres of 22mm before it gets to the feed pipe

 

[PhoenixServices]

I think I see what your saying about the new direct 22mm run instead of going to the old airing cupboard. As all the pumps and valves will be down in the garage I would of thought.
Can you upload a drawing just to double check we are on the same page.

 

[1animal1]

Will do, I'm going to put it together again before posting, to give it some scale. Currently the pump and electric switch for the hot water/rads reside in the airing cupboard, but they will be in the garage with the new set up... The diagram will show everything

 

[1animal1]

This is the best i could knock together, apologies for the messy writing. All rads are fed by the 8mm manifolds apart from the bedroom above where the boiler sits - these two rads have a 15mm run to the tail of the main rad feed - all pipes on this map are the 22mm main feed, 22mm rad feed, 22mm rad return and the hot water return from the cylinder coil which taps into the rad return.

The airing cupboard house the vent pipes, the pump and electronic valve.

I was proposing putting in place a 22mm pipe to meet the rad feed which stops at the top of the stairs - the new boiler/cylinder will be in the garage which is on the same wall as the current boiler. The main feed and hot water return can then be removed from the system once the new system is in.

 

[jtsplumbing]

Is there any reason why you cant reposition radiators ? the bottom 3 seem a long way from main pipe runs, new radiators don't have to be under windows,

 

[1animal1]

They are pretty long runs. The main bedroom definitely can't be changed as the rad sits in a bay window , the rest of the walls are taken. Ironically this is the longest run at about 5 metres.

The two smaller bedrooms off the landing could be looked at, but the run is already in place and the only thing I'm saving is a few metres of pipe.

I was going to ask about the bedroom above the boiler, it has two rads connected via 15mm to the 22mm rad feed. Obviously if I extend the rad feed then these rads will have their pipework reduced. But I can't help but think that if I remove the furthest small rad it'll remove unnecessary pipes and joints... I'll measure the rooms/windows/rad sizes and post up if that would be useful as a gauge?

 

[jtsplumbing]

Are all these rads fed by 8mm pipe, maybe you could extend 22mm to rad in big bedroom then 15mm along into other 2 bedrooms keeping inline with rads if you don't want to re-site them