Radiator not heating up

[del mar 2]

It was Bl**dy cold this morning !!

The large radiator in the living room doesn't heat up.

The pipe into the TRV is red hot.
I removed the radiator stuck a hose pipe through it for 5 mins to flush out, clean and made sure the valves were open and working.

The TRV is not stuck, the radiator has been bled but it wont fill with hot water.

What am i missing here ?

Thanks

 

[Oneball]

The tap at the other end?

 

[Oneball]

How did you bleed it if it won’t fill?

 

[mowlas]

If you remove the TRV completely, you will see the pin that pushes the valve closed and open. If the pin is stuck in the down position then the valve itself probably needs replacing (not the TRV). You can test this by trying to pull the pin up (gently) with a pair of pliers. If it does come up, that’s your culprit and you’ve also temporarily got it working until you replace.

 

[bigbob]

If you remove the TRV completely, you will see the pin that pushes the valve closed and open. If the pin is stuck in the down position then the valve itself probably needs replacing (not the TRV). You can test this by trying to pull the pin up (gently) with a pair of pliers. If it does come up, that’s your culprit and you’ve also temporarily got it working until you replace.

Also spray it with a bit WD40 first and, possibly, a gentle tap with a hammer.

 

[P R]

I had similar after a system refill. Could be airlocked, so try closing other radiators and the pressure should move it. Worked for me

 

[del mar 2]

TRV and lock shield are fully open.

PR - i have closed the others downsairs and left the girlfriend in the house, hopefully it works or i will be in trouble when i get home

 

[mowlas]

TRV and lock shield are fully open.

PR - i have closed the others downsairs and left the girlfriend in the house, hopefully it works or i will be in trouble when i get home

So you’ve unscrewed the TRV and checked that this pin is in the up position, not stuck down?

 

[Scaf]

I have just had exactly this problem, both valves ok but no flow.

In the end I turned off every other radiator / towel rail in the house and left the heating on, bingo, flow restored and been fine ever since

 

[jasst]

It sounds like you either have an air lock, or pipework blocked with sludge, remove rad again and make up a fitting to attach a hosepipe to the valves, only needs to be a short length and put end into bucket, open valve and see if you have any flow from that pipe, do each one in turn, if you have no flow from one then you have blocked pipe, did this yesterday for a customer (this is what I do for a living).

 

[del mar 2]

thank you.

Jasst will give that a try.

How did you then un block the pipe ?

 

[del mar 2]

So you’ve unscrewed the TRV and checked that this pin is in the up position, not stuck down?

View attachment 109031

yes quick squirt of WD40 and a pair of pliers fixed that

 

[jasst]

thank you.

Jasst will give that a try.

How did you then un block the pipe ?

That's when the fun begins! Switching on the heating so the pump is running may help, if youhave a pressurised system as oposed to gravity fed, then increasing the pressure may help, you can also get cleaning chemicals which you introduce into the system and let them work their magic for a few days , I have resorted to aqua vac trying to suck the blockage free, and using my pressure testing equipment to try and blast it free, last resort is to cut out affected section of pipe and replace with new.

 

[RodTungsten]

That's when the fun begins! Switching on the heating so the pump is running may help, if youhave a pressurised system as oposed to gravity fed, then increasing the pressure may help, you can also get cleaning chemicals which you introduce into the system and let them work their magic for a few days , I have resorted to aqua vac trying to suck the blockage free, and using my pressure testing equipment to try and blast it free, last resort is to cut out affected section of pipe and replace with new.

Morphic resonance! Just returned from the village hall after improving the heat: we freed two TRV pins and blew s**t out of the lowest part of the pipe work - hose on drain leg, increased fill pressure and alternated flow using some conveniently placed isolator valves.

 

[del mar 2]

Update

Turned off all rads bar the problematic one.
It got hot, however when i turned the other back on it goes back to being cold again.

It is an old combi - pump getting tired ??

It is more annoying than sorting out the Ghibil as there are no ECU's attached to the radiator !

 

[Oneball]

That sounds like there’s a significant restriction within the problem radiator or it’s pipe work.

 

[Harry]

Update

Turned off all rads bar the problematic one.
It got hot, however when i turned the other back on it goes back to being cold again.

It is an old combi - pump getting tired ??

It is more annoying than sorting out the Ghibil as there are no ECU's attached to the radiator !

I’d try opening up the valve a bit at the other end of the problem radiator.

 

[Harry]

I had a similar experience with the radiator at the furthest end of my heating system from the boiler. It doesn’t take much to unbalance a system.

 

[Scaf]

Tomorrows job