convert single pipe cebtral heating into two pipe system.

[littlepigeon]

Hi all,

As the title suggests I would like to convert my old out of date one pipe central heating into a more efficient and upto date two pipe system.

At present we have had an A rated 24kw condensing central heating only bolier installed duedue to the old boiler breaking during a big flood. Ideally I would go combi but that's extra expense I could do with keeping to an absolute minimum.

If I was to slowly do this myself over summer (just laying pipes for now) is there any good guidelines I could see anywhere with regards to pipe sizes to use etc.. Best practises for longest pipe lengths from main pipe to radiators etc..

Any advice on pitfalls when doing this kind of work and what to avoid would be mega helpful.

A couple of questions I already have would be ....

- could I just run a second pipe around the house next to the existing one?

- does the main flow and return just run under the floors on the fist floor with all radiators t-ing down to the ground and up on the first, or would you run the pipe throigh the downstairs then up to the upstairs meaning all pipes from main pipes to radiators would be kept to an absolute minimum length?

- is there anything wrong with using compression fittings over proper soldring? I'm comfortable with compression but not soldering.

Many many thanks.
Gav

 

[dextrous]

Whereabout in Cheshire are you?

Anyway 22mm flow and return, tee'd so you have upstairs and downstairs main circuits, with 15mm spurred off these to and from the rads.

Depending on what you eventually want, consideration for separately controlled zones may be desirable (for example havine the main room rads on an independently controlled circuit from the bathroom - this will allow towels to be warmed and dry during the summer onths when the rest of the house is unheated), or essental if you have a conservatory which should have an independently controlled circuit.

 

[tamz]

If you have plenty time just start from scratch as following the one pipe loop with another pipe will give a system with a far greater water content than necessary, therefore bigger bills.
Plan you new system and pipe runs. Have a google for 2 pipe system and work it out to suit your house. Run the new pipes up to front of the rads so they are easy picked up when ready. Follow what Dex says about sizing and reduce to 15mm for last 2 (maybe 3 depending on output) at end of runs. You won't need to bother too much with sizing for lengths if you have a normal size house.
If you are not too good with the copper and don't trust your soldering, use plastic. It is like Lego, even the weans could do it. You need copper for 1st meter or so from boiler and you should use it for any visible runs because plastic looks like a dog phishin in the snow (can still use plastic fittings or Cuprofits look better).
Fire in it is not hard to do.

 

[dextrous]

Fire in it is not hard to do.

especially as you're pipes are going to be dry!

Forgot to comment on your using compression - not a good idea really Far more expensive than endfeed for a start, and you'll be going through a fair old number of them, especially 22-22-15 and 22-15 reducers.

My advice, for what it's worth, is to sign up for the introduction to plumbing workshop (for the C&G 6129 qualification). This will take about 4 days to complete, and on it you will learn the basic skills of bending pipes accurately, measuring pipes, plus how to sweat solder joints. May cost a few hundred pounds, but it will save you a lot in the long run, plus you'll be able to do a bit of simple plumbing jobs for friends and family who may even pay you for it!

 

[tamz]

My advice, for what it's worth, is to sign up for the introduction to plumbing workshop (for the C&G 6129 qualification). This will take about 4 days to complete, and on it you will learn the basic skills of bending pipes accurately, measuring pipes, plus how to sweat solder joints. May cost a few hundred pounds, but it will save you a lot in the long run,

Dex if he wants to pay me and i've nothing better to do, i'll fly down with one of the boys, fit the lot of the pipework in a day (in copper (unless he lives in a BIG house might go into 2)) and fly back the same day for less than the price one of these courses and he would learn more by watching me (as long as he keeps out my way)

 

[littlepigeon]

Whereabout in Cheshire are you?
.

Thanks for the info, I'm in Northwich.

The house is a very long thin house, 3 bed one bathroom upstairs, r reception rooms, hall and kitchen downstairs.

The boiler at present is at the back of the house so when you say t off do you mean run a flow and return along the downstairs rooms and the same again upstairs? The house us an old edwardian property so hiding pipes downstairs is difficult due to solid walls. At the moment I think all downstairs rads appear to be fed off the single pipe running under the floor boards upstairs.

 

[Agile]

Better to ask an older plumber if you could go with him FREE for a few days to lend a hand and get an idea of whats involved.

If you do that then make it clear you are NOT going to operate in competition with him.

Tony

 

[dextrous]

he would learn more by watching me (as long as he keeps out my way)

Am not entirely convinced that I'd want him to learn what you could teach him.

 

[dextrous]

Thanks for the info, I'm in Northwich.

bit too far - would have offered to come round for a cuppa and a free bit of advice for you

The boiler at present is at the back of the house so when you say t off do you mean run a flow and return along the downstairs rooms and the same again upstairs?

that was the idea

The house us an old edwardian property so hiding pipes downstairs is difficult due to solid walls.

are the floors solid, since it's under those that the flow and return need to run

At the moment I think all downstairs rads appear to be fed off the single pipe running under the floor boards upstairs.

so each downstairs radiator has a couple of pipes running up the walls back to the main pipe?

 

[tamz]

Am not entirely convinced that I'd want him to learn what you could teach him.

Well that may be true I still can't suck eggs though

 

[dextrous]

Well that may be true I still can't suck eggs though

Anyway tamz, whaddya think to doing it all in lcs. Love to see you do that in a day

 

[tamz]

Whats ics

 

[dextrous]

Whats ics

lcs = low carbon steel.

 

[tamz]

Fk i'm too old for that
Be there for the summer

 

[dextrous]