RAD NOT FILLING

TOEJOE

Hi
I have just removed a twin radiator from our bathroom. I had difficulty bleeding the old radiator as the bleed screw was busted. I managed to remove the old bleed screw and replace it with a new one to do this I had to remove the radiator (long story). When I replaced the radiator I opened the valves (one thermostatic) and opened the bleed screws some air came out and then stopped, no water came out.The radiator is heating at the lower hot input side of the radiator but not on the output side (obviously very little water in the rad). I assume its a air lock in the system or a blocked valve . I am going to try a few pieces of advice I saw on the internet close off all valves in the system and leave this radiator on to see if the radiator fills (with boiler on). The question I have is there is a red expansion chamber (with what looks like a bicycle valve on it) in the attic and also a small header tank for the system ,will this chamber create a problem for me . I do not know how to pressurise the system do I need to ?.The boiler was replaced about ten years ago.

The boss is freeezing, no dinner this evening!!!!!!

Help

G2ECE

its a little strange that there would be a header tank and an expansion vessell in the one house unless there is a back boiler or stove also. The header tank would suggest that its an open system but the red vessel suggests a sealed system. If there is a pressure gauge about then its probably sealed. Look for a silver braided hose with a valve on one end to top up the system, bring the pressure to 1 bar and then try bleed the rad. If there is no gauge then it is most likely an open system. The rad may not be venting for you if there is dirt stuck at the outlet, try taking out the vent pin and clear the outlet with something narrow like a sewing needle.

Hard to give exact advice without seeing the system.
Best of luck!

TOEJOE

Thanks for the reply
The red expansion vessel is connected to where the overflow to the header tank was i.e for where the water expanded when heated. I am not familar with this system there is no loop to pressurise the system. A reg plumber put in the expansion vessel. The question is how can I get water into the radiator or get rid of the airlock if that is what the problem is???

Thanks again

G2ECE

Sounds odd that an expansion vessel would be fitted there, you need to establish if the system is open or sealed before you can determine how to fill the system to remove the air. It may well be that its a cistern fed sealed system, adapted from an originally open system. Is there water in the header tank? Also, given that you have done some work with the rad, make sure that the hole the air comes out is not clogged with sludge/dirt.
other than that, I can only suggest you ask a plumber to have a look at the system for you.

TOEJOE

Hi
Thats exacly what it is, its a cistern fed sealed system,does this system need to be pressurised and if so how do I go about doing that?.There is water in the cistern,I cleaned it out yesterday brown gunk in it.Will keep looking thanks.

G2ECE

If its cistern fed then you can't pressurise the system. If there is air in the system, you may have to shut down other rads and the balancing valve at the cylinder to get the air pockets to move, whilst doing this have the circulation pump operating but not the boiler, if you can. If there was sludge in the cistern, its possible that its in the system too, you may wish to consider putting in a cleaning agent to flush it out, and possibly an inhibiting agent after to keep the system clean thereafter.

TOEJOE

Hi
There is no balancing valve at the cylinder and the pump is always on when the heating is on. I may have to remove the expansion chamber and hope by playing with the system get rid of any air locks. I did not put the new boiler in the plumber decided to have the pump always on when the heating is on.


Thanks Again