All radiators on one side of apartment cold

[belgianwaffle]

well yes...if the pipes are warm then thats where the blockage is..in the rad / valve

Sorry, my bad; I hope this is clearer:
1) On a working radiator, when the TRV is closed, the twin pipes at the bottom and the pipe going to the TRV still get warm.
2) On a non-working radiator, when the TRV is closed (or even open), all pipes remain cold.

In other words, it's as if the hot water never makes it past the last hot radiator in the circuit.

The cold ones are cold throughout, including the pipes. That's why I thought the blockage would be elsewhere in the system.

 

[cross thread]

did everything work before the rad alteration ? Have you a pict of the new rad position / pipe work

 

[belgianwaffle]

did everything work before the rad alteration ? Have you a pict of the new rad position / pipe work

Everything worked fine. I don't have any pictures of the pipework, though.

 

[martygturner]

So is that rad turned off ?

 

[belgianwaffle]

So is that rad turned off ?

The one in the bathroom? No. It's the one closest to the boiler and works fine.

 

[martygturner]

Try for an airlock then... Take off all the TRV's,( make sure that all the pins push in and pop out), so that the valves are open. Start at the furthest rad from the boiler and bleed at least 100ml of water out, keep going backwards towards the boiler, keeping the pressure at 1.5bar. Do it when the system is cold and off. Run the system with all the TRV valves off.

IIf that doesn't work you have some crud in the systems probably when the rad was moved some rubbish got in the pipe and has lodged.

 

[belgianwaffle]

Try for an airlock then... Take off all the TRV's,( make sure that all the pins push in and pop out), so that the valves are open. Start at the furthest rad from the boiler and bleed at least 100ml of water out, keep going backwards towards the boiler, keeping the pressure at 1.5bar. Do it when the system is cold and off. Run the system with all the TRV valves off.

IIf that doesn't work you have some crud in the systems probably when the rad was moved some rubbish got in the pipe and has lodged.

I finally figured it out. After I ran the system with all the TRVs off, it finally started working. Then I put the TRVs back on and the problem came back. I then started opening and closing the individual TRVs until I found the culprit - the bathroom radiator (the one that was moved from one wall to another). Apparently, the cold ones work only when the valve on the bathroom one is open.

Does this now mean the contractor will have to break the bathroom floor again to reconnect whatever he messed up?

 

[martygturner]

Yep, he has not kept the flow and return pipes he has just plumbed in one end of the flow into the bathroom and then run it out to the next rad.

You had the bottom one now you the top one, shut off the first rad and with trv's on the other rads the system has to run in reverse..........you could just run the bathroom one all the time and the rest would work as normal.

 

[belgianwaffle]

Yep, he has not kept the flow and return pipes he has just plumbed in one end of the flow into the bathroom and then run it out to the next rad.

You had the bottom one now you the top one, shut off the first rad and with trv's on the other rads the system has to run in reverse..........you could just run the bathroom one all the time and the rest would work as normal.
View attachment 286637

I've just had a talk with him. He claims they didn't touch any of it, but believes that one of the guys may have accidentally swapped the flow pipes on the boiler side after they finished moving the radiator. That... would explain a lot, especially if that one and the three cold ones are on a separate circuit. Let's see.

 

[martygturner]

Good luck - but at least your warm and toastie

 

[belgianwaffle]

So, turns out the actual problem was the 2-pipe valve which lacked a bypass that would allow the hot water to flow to the other radiators with the TRV closed.

Mystery solved.

Many thanks for all the help.