Extended RAD cold

[divvy]

We've had some minor building work, we've had a wall knocked down and the rad moved to the opposite wall. The heating system is Single Piped, I've connected both ends in plastic running under the floor, which has been fully tiled now, so no access..

The whole system runs lovely, but I am getting no heat to the new RAD. If I purge the water through the rad valve I get hot water, but once the rad is back on the wall no flow.

Due to the extra pipe run the only conclusion I can come up with is the pump, although it heats the rest of the house. The pump Grundfos is about 9 years old, could it not be man enough to cope with uneven run in plastic?

 

[Dan Robinson]

. The heating system is Single Piped, I've connected both ends in plastic running under the floor, which has been fully tiled now, so no access..

The whole system runs lovely, but I am getting no heat to the new RAD. If I purge the water through the rad valve I get hot water, but once the rad is back on the wall no flow.

Think you're screwed then.

 

[Terry7556]

Must read posts properly before posting ffs

 

[St0rmer66]

No chance of that working as it is. Floor up again or cold room, your only 2 choices. Single pipe systems work very well but only if set up correctly.

If you really want to exhaust all options before taking the floor up you could try piping the pipe coming from the direction of water travelling round the system into the TOP connection of the radiator (not the bottom as it probably is) with the outlet side at the bottom. Make sure you have only manual valves on it, fully open. TRV's are generally far too restrictive to work on a one pipe system unless you buy the very expensive 'high lift' ones designed for them. That "might" coax some flow into it but I wouldn't bet on it.

You should have done some research on this before putting the floor down .

 

[divvy]

Looks like I could be stuffed then!!!

Sad times!!!

 

[jackthom]

Do you have easy access to any of that pipework up to the point where it joins the one-pipe system? I'm thinking about the possibility of another pump in that radiator's run but it's a bit of a bodge and it would have to be readily available for servicing etc.