Why is the Trv leaking after removing radiator

[Pisces67]

I've isolated the trv end and lockshieds end to remove a radiator, however the the trv is still aklowong drips of water to cone through. How do I stop it completely?

It's coming from the main inlet pipe face

Thank you

Thanks

 

[ShaunCorbs]

1/2 blanking cap end should sort you out

 

[Pisces67]

OK thanks, will do that. Is there any reason to be concerned if the d trv does not seal fully for future reference

 

[ShaunCorbs]

Some trv s don’t totally could be either the head isn’t on correctly/ fully tighten

 

[Pisces67]

Fair point. Is it best to take the trv head off and unscrew fully to an open position from * to 7 and then replace back onto the needle head at position 7bwhich is fully open?

 

[ShaunCorbs]

Fair point. Is it best to take the trv head off and unscrew fully to an open position from * to 7 and then replace back onto the needle head at position 7bwhich is fully open?

yes and tighten the collar down then switch / turn the trv off but don’t do it now else you will flood yourself

 

[Pisces67]

Just bought 1/2 inch blanking nut but is too small, I think it should be 3/4 to screw directly onto the threaded trv open end, is that correct?

 

[ShaunCorbs]

Just bought 1/2 inch blanking nut but is too small, I think it should be 3/4 to screw directly onto the threaded trv open end, is that correct?

trv will be 1/2 lockshield will be 3/4

1/2 should measure around 20mm od

 

[Pisces67]

Hi the threaded trv outside dia is 25mm. Is there a blanking nut for this thread so I can cap of the trv Insitu. So in effect like tightening up with the union nut on the radiator

 

[ShaunCorbs]

you are correct its 3/4 never seen a trv in domestic with a 3/4 nut

 

[Pisces67]

It's valliant trv from the 90s

 

[Stigster]

A 3/4 blanking cap should fit that thread but I cannot absolutely guarantee that. Like Shaun says, I too have never seen a 3/4" TRV outlet in a house before but there it is, looks like that's what you've got.

 

[Pisces67]

A 3/4 blanking cap should fit that thread but I cannot absolutely guarantee that. Like Shaun says, I too have never seen a 3/4" TRV outlet in a house before but there it is, looks like that's what you've got.

Yes these are from 1996, valliant.
This is the current modification I have made follwing the purchase of the 1/2 inch blanking nut,

 

[Stigster]

That's a good way to overcome the problem. Well done!

 

[Pisces67]

That's a good way to overcome the problem. Well done!

Before I redose with sentinel X100, is there any point in putting in a cleaner, emptying and then dosing. Clean water came out of the rad and only dark black fine debris water came out of the holes in rad.

 

[ShaunCorbs]

I wouldn’t just dose with x100

 

[Pisces67]

I wouldn’t just dose with x100

What do you recommend?

X400, run for a couple of weeks, drain and then add x100

 

[ShaunCorbs]

Just add x100 when your finished