radiator valve tail piece

[michaels]

Just a quick question. Do all manual radiator valves have a common interface between the valve body and the valve tail piece? The reason I ask is that I have bought some new valves for a radiator that i'm taking off the wall and then putting back again. Will I be able to screw the new valves to the old tail piece?

Many thanks.

 

[corgiman]

The interface is called a union as is normally half or three quater inch so be careful which one you by, older ones normally 3/4 new ones 1/2 inch

 

[nik_fatw]

The thread size may vary.

 

[michaels]

Thanks for the replies.

I was just wondering about the commonality of the ball joint with a hex hole up the middle configuration. I have since been informed that this is quite common... i don't know if you agree?

 

[michaels]

Another quick one.... when fitting the new valves is it ok to use the old compression olive on the supply and outlet pipes. If I wrap a bit of PTFE tape around them will they be ok?

 

[breezer]

for the price of an olive V hassle (and leak) i would get new olives

 

[MANDATE]

If using new olives, I suggest copper ones against brass as they are softer.
The problem is removing the old olives without sawing through and damaging the pipe and allowing water to leak through the inside of the olive.
I would first use the old olives without the ptfe tape and if not sucessful then try the tape or other sealant. One of the best sealants I have found is 'Hermatite Red' from Halfords, it never sets rock hard. The first bit out of a new tube is a bit too watertry. There are other good sealants no doubt.

 

[oilman]

I may be wrong, but I normally use the old olives and nuts and just smear some jointing compound over the olive (Waterhawk) but other compounds would do.

Carefully sawing a slot almost throughthe olive and using a screwdriver to split it avoids damaging the pipe.

 

[michaels]

many thanks for the replies.

I am doing a de-sludge at the same time so i'll use the old olives and if they leak i'll stick the new ones on when i do the final flush. i have PTFE, jointing compound, and new olives... so all bases are covered.

thanks for the advice.