how to remove this TRV ?

[Nobbyone]

Hi,

Could anybody tell me how to remove this TRV from its valve? Thanks

 

[Masood]

The black nut next the silver body of the valve will unscrew.

 

[Nobbyone]

The black nut next the silver body of the valve will unscrew.

The black nut does not move much, just a quarter turn. It has a small tab on it. Would the quarter turn be enough to allow me to pull it off?

 

[hammers4spanner]

whack it with a hammer then

 

[Masood]

The black nut does not move much, just a quarter turn. It has a small tab on it. Would the quarter turn be enough to allow me to pull it off?

It might be that the valve head pushed on and the nut just locks with a quarter turn. have you tried pulling the head after undoing the nut as much as it will go?

 

[JCplumb]

I've seen quarter turn (maybe quarter, didn't get my protractor out ) once in an old dears house, she had one of those boilers that are behind a hinged radiator to give you an idea of the age of the install.
It was just a quarter turn then a wriggle to get the TRV head off, if I remember correctly it was a Drayton valve, could of been Honeywell though, but was definitely a well known valve manufacturer.
Have you tried to wriggle the head off with the nut in varying positions?

 

[joni os]

It's the Knurled nut in centre of picture. Unscrew 3 to 4 turns and TRV will pull off to right.

 

[Nobbyone]

there is no thread to unscrew. The black nut appear to just tighten its grip on the valve head.

 

[hammers4spanner]

allen key

 

[joni os]

Sometimes valve clamps on flange and this clamp action tightened by nut. With nut slack rotate whole of valve to locate grooves in flange where head can be removed.

 

[Sparkgap]

The black nut does not move much, just a quarter turn. It has a small tab on it. Would the quarter turn be enough to allow me to pull it off?

Isn't there a grub screw as well? Usually just rotate the black lock nut to slacken the grippy bits then you should be able to unclip/pull the head away from the body.

 

[Nobbyone]

I think it was a Honeywell. Can't find a picture of it anywhere. Petty old though, system has a manual clock timer with movable metal on/off hands like a shop lights timer.

I will try all the suggestion this afternoon.

 

[Dotty]

allen key

Yep..

 

[AlexGas]

whack it with a hammer then

 

[Nobbyone]

Hi all,

It was a allen headed grub screw located in the protruding tab part of the black metal ring. It was an old Danfoss head.

Thanks to all.

 

[Nobbyone]

Isn't there a grub screw as well? Usually just rotate the black lock nut to slacken the grippy bits then you should be able to unclip/pull the head away from the body.

Spot on.