Single Radiator not working

[Mike78]

Hi all,

I am hoping that I can pick your brains again. I have just installed an Ancona 1800mm high and 10 double columns wide radiator. This radiator was moved to the other side of the room, and I have had the floorboard up to extend the pipework using push fit with copper for the down pipes. The existing system that was there was push fit, so I just made cuts and added couplers - all with inserts, and having run it for a few Horus with the boards still up it is 100% water tight. The place that the radiator has gone into is the front room downstairs in a 2 storey house (Ground, First, Second)

I have now had the thing apart three times trying to work out why no hot water is going to the radiator. To summarise what I have done:

1) The radiator is 100% the right way up - red bung at the top which was removed and blank plate put in its place
2) Flow is on that side bottom left with return on the right
3) Diverter spring fitted into flow side
4) Everything water tight
5) TRV is a nickel one which must be on the flow side - it is 100% on the flow side

The flow pipe is red hot, the TRV body is red hot but not 1 millimetre of the radiator is even slightly warm. I thought it was a number of things such as the diverter not working, or my plumbing in things the wrong way around, but no hot water will enter the radiator. I have tried:

1) Bleeding radiator
2) Shutting off both valves and unscrewing bleed valve nut - Then opened TRV and got a large pop of air and then loads of water - ran that into a bucket for a good 30s until flow went to a dribble - tightened all back up and no good.
3) Pulled apart return coupler that I had installed and large high pressure cold water hit me in the face so sealed back up again - there is therefore definitely flow coming from the radiator.
4) Bled the entire house - all air out and all radiators working perfectly, but for some reason no water passing through the radiator.

It seems as though the hot water gets to the TRV and then just stops. There is nothing flowing through the radiator and out of the return side. This isn't a case of just the bottom bit of the radiator getting warm and the top bit cold, there is literally no hot water whatsoever getting into the radiator. I thought at first the diverter spring was jammed and preventing water from entering, and so I took it out to test and still nothing going through he radiator.

I am going to be calling my plumber contact tomorrow as this is obviously past my ability to fix, but posting on here incase anyone has any idea? Don't think it can be the boiler not having enough juice as why would it heat the rest of the house and not this radiator? There are only about 7 other radiators on the circuit anyway. I've literally removed the radiator that was there and put couplers on to extend the piping about 2m to put it on another wall. I have made no other changes to the pipes / layout of anything.

Thanks for reading if you have got to the end!

 

[Gasmk1]

Trv faulty, also do you have the arrow on try (flow direction) the right way have you blocked the entry to rad with too much ptfe

 

[Ben-gee]

Swap the trv for a normal wheel head valve and see if that sorts it.
Then you know it’s the trv and can replace that.

 

[Mike78]

Thanks for taking the time to reply. Both the radiator valves are brand new and I check them after pulling it all apart the first time. The problem has actually resolved itself. The other half locked herself out of the house earlier, and was sat outside for 2 hours whilst I came back from work. The boiler had been set to level 2 out of 4 for the radiator heat, and because she was shivering I put it all the way to max. After 20 mins, the column radiator was pumping out heat.

From my DIY level of knowledge, it seems that the new radiator I installed is likely at the end of the loop before the water returns to the boiler. Hot water was therefore getting all the way around the house and then had lost too much heat to heat up a large column radiator, therefore the TRV was hot but the radiator wasn't. I will try to balance the system a bit later to get a bit more heat to that one, but it seems as though my other half's bad luck was my good fortune as otherwise I wouldn't have thought to turn up the boiler!