Steel pipe one pipe system adaptor fitting

[RayPlumb]

Ive got a client with an old one pipe system in steel pipe. They want a radiator put in the bathroom where pipe run runs under floor along wall. I can access short run of pipe. Was thinking of cutting pipe putting 22mm copper in cut out section with flow and return rad tap ins. Then back to old steel. Any ideas of type of fittings for this. No room to cut new thread on steel pipe. Was thinking of primofit but not sure if suitable for heating...
Any suggestion. ..
Thank

 

[ShaunCorbs]

As it's a one pipe system

Either do it right or not at all

Needs to be in steel and use diverter tees also o would keep it threaded

 

[Last Plumber]

Ive got a client with an old one pipe system in steel pipe. They want a radiator put in the bathroom where pipe run runs under floor along wall. I can access short run of pipe. Was thinking of cutting pipe putting 22mm copper in cut out section with flow and return rad tap ins. Then back to old steel. Any ideas of type of fittings for this. No room to cut new thread on steel pipe. Was thinking of primofit but not sure if suitable for heating...
Any suggestion. ..
Thank

I would do it in steel. Cut pipe and take the length out, thread it, put your two tees in and a union and put it back. Keep your tees as far apart as you can (obviously within reason). Make sure you use the correct rad valves. You can use copper on the branches if you like but if the rest of them are done in steel it will look better the same way. It's easier to do it top one side and bottom the opposite (if using steel branches) unless the rest are top and bottom same side?
Hope this helps.

 

[RayPlumb]

I would do it in steel. Cut pipe and take the length out, thread it, put your two tees in and a union and put it back. Keep your tees as far apart as you can (obviously within reason). Make sure you use the correct rad valves. You can use copper on the branches if you like but if the rest of them are done in steel it will look better the same way. It's easier to do it top one side and bottom the opposite (if using steel branches) unless the rest are top and bottom same side?
Hope this helps.

Thanks for your reply
The system had new rads modern put in 15yrs ago and have copper branches.
My last experience with steel was in collage a long time ago.. Once I thread the pipes how do you avoid unscrewing the opposite end ..? Can you do a reverse thread on one end. ?? How do you get round the exact pipe size to fit it in. Where you would use a slip coupling if it was copper..

 

[ShaunCorbs]

Union fitting

 

[Gasmk1]

you have 2 options you can use split unions or you could go old school and use a long thread.

 

[Last Plumber]

Thanks for your reply
The system had new rads modern put in 15yrs ago and have copper branches.
My last experience with steel was in collage a long time ago.. Once I thread the pipes how do you avoid unscrewing the opposite end ..? Can you do a reverse thread on one end. ?? How do you get round the exact pipe size to fit it in. Where you would use a slip coupling if it was copper..

As both above said. Long thread or union. If you use a long thread you'll need the right lock nut so it will be easier to use a union. I don't know what you mean about the exact pipe size?
If you mean it will be tight to get it in and a struggle under the floor, that's just plumbing. There is no easy way, brute strength and ignorance usually comes in!!

 

[RayPlumb]

Just noticed today that there is a auto bypass on the system in the plant room. Surely you would not need one on a single pipe system with 7 rads. ?? would you?

 

[Last Plumber]

Just noticed today that there is a auto bypass on the system in the plant room. Surely you would not need one on a single pipe system with 7 rads. ?? would you?

No not normally. A one pipe system is a loop.
Is it definitely a one pipe?
Is this domestic?

 

[king of pipes]

I have done loads of this type of work over the years the only way to install another rad is by gaining access to the pipework where you can remove a section of pipe thread it in situ using a hand held rems or other treading machine,fit a swept iron tee ensuring the direction of flow is correct the same will need to be done for the return and the pipe rejoined back together using a flat face navy type union with the other tee a nipple and tee sweeping back to the direction of flow usually connected top and bottom opposite end and be the correct type of valves normal trvs dont work on this type of system , the valve you describe in the plantroom is probably a double regulating valve to balance the flow of water through that circuit. I very much doubt this will.be possible as you are restricted on space but that's the correct way to do it . Regards kop

 

[RayPlumb]

No not normally. A one pipe system is a loop.
Is it definitely a one pipe?
Is this domestic?

It is a cottage that is attached to a large house hence the plant room. Until I actually dig out some screed to follow pipes between rad tails wont know 100% but the steel pipe sticking through suggests possible one pipe. Want to make sure I'm 100% on what to do if it is a one pipe before I quote or start.

 

[64degrees]

Barrel pipe works a very different beast from copper, if it’s the first job you doing I’d recommend getting a subby in. KOP nailed it, navy union and all. He’ll be explaining the difference between GF and Crane fittings next …