Balancing with TRVs

[Agile]

Did the op state what boiler he had before i made my post? Or can i mind read?

I doubt that you can mind read. So if not, then you adust for 11° on a standard and about 15-20 on a condensing boiler.

Statistically, I would expect that more systems with TRVs now have condensing boilers.

Tony

 

[Gas2Air]

I doubt that you can mind read. So if not, then you adust for 11° on a standard and about 15-20 on a condensing boiler.

Certainly wouldn't read yours Tony, got issues of my own!

 

[D_Hailsham]

surprised how critical the lock shield setting was.

If your L/S valve is open more than one turn, its probably open too far and not having any effect on the flow.

By restricting the lockshied valve i,m restricting the flow into the rad, not out of the valve

It does not matter which end the L/S valve is. It is restricting the flow through the radiator. The radiator is full of water so, if a litre per second is flowing into the rad, a litre per second must be flowing out of the rad.

Incidentally, did you know that Drayton TRV4 have integral balancing? If you take the head off and look at the body, you will see a black ring with numbers 1 to 6. You need a special box spanner (got two free from Honeywell edit: I meant Invensys). Rotating the dial, so a number lines up with a mark on the chrome, puts a defined restriction in the side entry. The pics below show the restrictions for 1, 4 and 6 (default-no restriction)

View media item 4862 View media item 4863 View media item 4864

 

[Agile]

It does not matter which end the L/S valve is. It is restricting the flow through the radiator. The radiator is full of water so, if a litre per second is flowing into the rad, a litre per second must be flowing out of the rad.

That would be a very noisy rad at 60 li/min !

6 li/min or less is more typical!

Now I did not know about the TRV4 having an adjustable restriction!

It also surprises me that you got a special spanner from Honeywell which fitted the Drayton valve.

Tony

 

[D_Hailsham]

That would be a very noisy rad at 60 li/min !

Just a number plucked out of the air.

Now I did not know about the TRV4 having an adjustable restriction!

Only found out about it when I came across Balancing TRVs on the Invensys/Drayton web site.

It also surprises me that you got a special spanner from Honeywell which fitted the Drayton valve.

Woops, meant Invensys. None of the local merchants, i.e. PTS had ever heard of the thing. So I emailed Invensys Customer support to ask where I could buy them and they sent me two for nothing.

 

[Richard C]

surprised how critical the lock shield setting was.

If your L/S valve is open more than one turn, its probably open too far and not having any effect on the flow.

I started them all off at ½ turn initially & all had to come down, most ended up around ¼ turn one or two were less.