Single pipe central heating system

[Memster1986]

Had a night mare of a day trying to get a new rad on a single pipe system working, 5 bed, 3 bath, 4 reception room house. all run on single pipe system with a ferroli 32 boiler.

New rad (1.7kw) apparently worked when installed now doesn't, has been fed from upstairs. which I thought was a bad idea on single pipe but still.

Couldn't get it working, no matter how I tried to balance the system. or with all other rads off, still wouldn't come on.

All down stairs rads, except this one have their pipes buried in a concrete floor, so aren't going to be changed.

My question, is if I T off from the flow and return, and run a conventional 2 pipe system upstairs, will the downstairs single pipe system still work? or am I asking for trouble? Or does anyone have any other ideas?

Thanks in advance

Memster

 

[mogget]

With a single pipe system, it's vital that the new rad is fed from a single pipe below it, not above it.

The water gets from single pipe to rad by convection which won't happen 'upside down'

 

[Memster1986]

So my boss telling me the rad was red hot after one of his other installers fitted the rad, is a crock of ****e then.

 

[mogget]

Let's put it this way, a rad fed from above, getting hot on a single pipe system would be close to a miracle.

The cold water in the rad is heavier than the hot water in the pipe, the only way it would get hot is if there were a restriction in the single pipe between the two valves.

 

[Memster1986]

That was my thinking but I haven't come across a lot of single pipe systems. So wasn't 100% sure.

Thank you

 

[PullerGas]

With a single pipe system, it's vital that the new rad is fed from a single pipe below it, not above it.

The water gets from single pipe to rad by convection which won't happen 'upside down'

Correct, you need to divert the single pipe to pass underneath the new radiator with tees directly below the valves & a vertical pipe rising from the tees to the rad valves. Special TRVs also required for SP system.
HTH

 

[Memster1986]

That's never gonna happen, the pipes are buried in the wall. there isnt a TRV, is jsut standard valves. I've advised the boss that the pipe work needs to be changed up stairs. It's between him and the customer now. Just not sure about running a conventional 2 pipe system upstairs and a single pipe system downstairs. As far as I'm aware, it should work?

 

[nortonj]

That's never gonna happen, the pipes are buried in the wall. there isnt a TRV, is jsut standard valves. I've advised the boss that the pipe work needs to be changed up stairs. It's between him and the customer now. Just not sure about running a conventional 2 pipe system upstairs and a single pipe system downstairs. As far as I'm aware, it should work?

Yes it will work. I added a rad to a single pipe system a while back just came off boiler flow and return creating a two pipe just on one rad, all work fine.

 

[muggles]

EDIT:Bowing to greater knowledge

 

[Agile]

There are many different types of SP systems.

The simple domestic type with all rads in series and the industrial system as used in schools where the rad sits above the pipe and has a gravity circulation through it.

Then a few mixed variants.

Tony

 

[PullerGas]

There are many different types of SP systems.

The simple domestic type with all rads in series and the industrial system as used in schools where the rad sits above the pipe and has a gravity circulation through it.

Then a few mixed variants.

Tony

Very true Tony. I recall as an apprentice altering & extending Single Pipe Drop gravity systems.
Most domestic systems were installed as I detailed.

 

[Memster1986]

Thanks for your help guys, all I needed to know is that it can be done the way I suggested, means I don't look an idiot. Lol. Boss is adamant that it was hot at time of fitting thou, and apparently the lad that fitted it is ex British gas...Least I know it can be done! Will T the 22mm pipe run 22 mm upstairs then run 15 mm feeds to the rads, having to reduce down where a couple have been done with 10mm (Hate 10mm pipe and don't see the bloody point of the stuff!!!!)

 

[PullerGas]

Thanks for your help guys, all I needed to know is that it can be done the way I suggested, means I don't look an idiot. Lol. Boss is adamant that it was hot at time of fitting thou, and apparently the lad that fitted it is ex British gas...Least I know it can be done! Will T the 22mm pipe run 22 mm upstairs then run 15 mm feeds to the rads, having to reduce down where a couple have been done with 10mm (Hate 10mm pipe and don't see the bloody point of the stuff!!!!)

LOL!!! Ex BG.
You do need to divert the main!!

 

[Memster1986]

Im guessing that means no faith in BG lol?

my dodgy paint drawing of what im going to do

 

[PullerGas]

Oh you're changing it to a two pipe system fella!!
No, BG guys are lead by the nose, limited construction skills & experience. If all you want is a guy that's sticking his probe in some old dears flue for twenty years, then they are the guys to employ.