Professional Trades People !... I Salute You !! I'm also in need of advice for 1 stubborn rad.

[Bad Brown Acid]

I have a 3 bed e.terrace.
1 rad in each of the 6 rooms (box room rad has damaged pipe so is turned off either side)all with TRV's.
In addition there's 1rad in hall and 1 on the landing. Both with old style on/off valve.
The Problem lies with the Bathroom rad. it's kinda on a dog's leg; as the bathroom is 3/4 of the way upstairs.
CH system is sited in upstairs back bedroom and every rad warms and heats to a decent temp. No major prob's there.
- I just can't seem to get the bathroom one to flow.
- I've tweaked and turned every valve in every manner of possibilities, in all rooms. Closing down LS's and opening them a fraction as they further from the boiler.
- I can trace the flow of all other rad's when I put the heating on. But because the bathroom 1 remains cold at both ends - I don't know where it sits in the circuit (presuming at the tail end).
- I've taken rad off and gave it a good flush, clearing it of any (very little tbh) sludge.
- When the heating is on and i bleed it , there is a flow coming in from the LS side. This is short lived however and the warm water flows away. Sad.
- I've had a thermostat to it and at times the pipe at the TRV side warms up. Recently it's gone from 10'C upto 19'C very slowly and both valves were on a trickle. The CH had also been on for most of the day.

I'm a proper novice at this, but want to learn along the way.
Folks with a Trade are worth their weight in Gold. Unfortunately i have no Gold so budget along we go. Any advice is greatly appreciated.
PS
A constant headache is the clanging and banging of pipes in the boiler cupboard. This is when the heatings been on for a while or a TRV has been adjusted in a room. Is this air in the system OR a load of Gunk ?
The Bangin also appears to happen when I've tried to make the flow reach the bathroom by closing down other rad's .
Any Help would be Great
Cheers

 

[Riley]

If you remove the rad do you get flow from both sides

 

[Bad Brown Acid]

If you remove the rad do you get flow from both sides

After reading posts in the forum last night and going over what i have checked. It did dawn on me about that very thing. Thanks for the advice and i'll take it off again and check.
That said, when i have bled the rad with the CH on (just to see if there's flow) the LS end allows hot water in - which dissipates asa i stop bleed. And after hrs of the CH running (and if i tweak the TRV in the right place) my handheld thermostat registers a trickle of warm flow creeping into the TRV side. Temp. can climb from 13C upto 18.8C But nothing consistant.
I shall take it off and check your advice.
Cheers Neil.

 

[Riley]

Could also be the pin in the trv being stuck and not allowing adequate flow through. Might be worth removing the head

 

[Dkdc71]

I had a similar problem with one rad mine was the trv head was sticking out beyond a sofa but in direct sunlight coming through the window was sensing the heat and knocking the rad off took me a while but got it in the end lol I agree with Riley check your flow and return pipes sounds like a bit of an airlock to me

 

[Bad Brown Acid]

Thanks for the advice !
much appreciated