lockshield conundrum

[novice1968]

I want to fit an Aladdin autovent on a towel rail that needs bleeding too often. Problem is i can't seem to close one of the valves - the one on the left image below, which seems to be the lockshield. The other one is fine - see image on right, which appears to be the temp control. Not sure if the valve has been bashed or I am just doing something wrong. Any tips?

If I cant close it, what odds on me getting old vent off and Aladdin fitted before house floods?

 

[oldbuffer]

1. If a radiator needs frequent bleeding it is indicative of a problem in the system. Fitting an automatic bleed valve may hide the symptoms but it won't cure the problem.
2. The spindle of your lock shield valve should have a square brass spindle at the top. Turning this clockwise (looking down on the spindle) will close the valve. Use a spanner to turn it so you don't round it over. Count the number of 1/8 turns required to close it, then when you have finished work on the radiator, re-open it the same number of 1/8 turns. This will preserve the system balance.
3. If the valve is very stiff to turn, slacken the gland nut 1/2 turn. The gland nut is the chromed hexagonal nut immediately below the brass spindle. Make sure you nip it up again when finished.
4. Your odds of doing it live without a substantial flood are poor.

 

[novice1968]

Thanks for the tips oldbuffer. I think the air loss is due to a weeping pipe/valve somewhere but I can't find it - old house, old gravity system. Anyway, it doesn't seem to be causing any issues I can see, so hence the auto vent. The spindle seems to have been rounded off already, which i think is my problem. I will loosen the glandnut as you suggest, and perhaps not try the live change trick!

 

[IJWS15]

You haven't got air loss, there is gas being generated by the system so potentialy corrosion somewhere.