Rad replaced in pressurised system remains cold

[damorad]

I'm sure this is something silly and I'll kick myself(promise) when I find the answer.
I have replaced a leaking radiator in the bedroom. It was a twin with single convector and I replaced it with a double with double convector. Not a problem in itself (I hope).
I put the bleed valve on the same side as the old one but despite bleeding it till it makes my wife wet (she a good bleeder), the rad remains cold. The feed pipe on the left is hot and the feed pipe on the right is cold (bleed nipple side). Is it a stuck valve? Any suggestions...

BTW the boiler is a Suprima 60 and its a closed system that normally operates at 1 bar....

help please...

 

[chrishutt]

If you look at some of the other threads describing similar problems you'll get some ideas.

 

[wilhelm]

are the valves either side open?

failing that hit it. hard.

it wont cure it, but youll feel better.

 

[damorad]

Thanks for your help....

Apparently it was sludge in the system blocking the return valve....
I closed off all the other rads and turned the CH pump up to 3.
I then whacked the valve on the return end with the handle of a screwdriver a dozen times and it seemed to do the trick...

The rad is now hot at the bottom as well as the top...

I'm suprised it was sludge bearing in mind its a new rad so next job will be a drain down and sludge removal (how do I do that?)

Thanks again all

 

[wilhelm]

at least you told us the end result. respect.

 

[damorad]

Apologies if this is a thicko question....

I have seen additives that remove sludge, does this miracle cure dissolve it to now't or is it full of false promises like Mr Muscle oven cleaner ...

TIA....

 

[wilhelm]

relax if its working leave it

.....incoming shells!! ...ill get me tin hat.