Lockshield radiator valves

[GlynnH]

Hi, I'm new to the forum and would appreciate a bit of advice:

I have just fitted a magna clean, flushed all the sludge out of the rads and put inhibitor in the system. I've got a combi with 10 rads. I'm going to balance the system properly using digital thermometers but just to get things up and running again: can anyone advise me on how many turns to open the lockshield valves? Before I started mine were all fully open - I have got TRV's on all but one rad. I have read they should be opened between a 1/4 and 1/2 a turn. This seems a very small amount as to fully open the valves takes a lot of turns - I am a bit puzzled why they were all left fully open.
many thanks in advance for any help and advice.
GlynnH

 

[Last Plumber]

Each system on its own merits.

You could start with 1/2 a turn, see how they feel, open up the cooler ones a bit more.

I would get them all feeling the same temp first and then check Flow and Return at the boiler.

I always aim for 11 deg between flow and return.

Heating is a very in depth subject and there are variations on methods and different opinions to contend with. You may get other ideas on here and other suggestions. I'm just giving you a very rough guide on the subject and avoiding getting into the technicalities.

 

[GlynnH]

Each system on its own merits.

You could start with 1/2 a turn, see how they feel, open up the cooler ones a bit more.

I would get them all feeling the same temp first and then check Flow and Return at the boiler.

I always aim for 11 deg between flow and return.

Heating is a very in depth subject and there are variations on methods and different opinions to contend with. You may get other ideas on here and other suggestions. I'm just giving you a very rough guide on the subject and avoiding getting into the technicalities.

Thanks, that's very helpful. If I aim for 11 degrees across my rads should the flow and return at the boiler end up about right?

 

[ShaunCorbs]

Thanks, that's very helpful. If I aim for 11 degrees across my rads should the flow and return at the boiler end up about right?

yes and anywhere from 11-20 is fine

 

[Last Plumber]

yes and anywhere from 11-20 is fine

So true Mr Shaun, so true.

You really want the return below 53 degrees or a bit lower if poss but this all effects heat output from rads and that's where the size of them matters and it all gets more involved.

You can increase the temp diff like Shaun says which does help sometimes.

That's why I said each on its own merits really.
That's where experience enters the equation.

See how you go, come back and tell us how you're doing