TRV wont fit radiator

[aaron1987]

Hello
First post on here so please be nice! lol
I would like to say first that I have found a lot of answers on this forum to problems i've had by just searching previous questions - and so have never needed to write a post. But this one has got me confused.

When taking a radiator off at the weekend the compression fitting on the input decided to give way - hence water squirting everywhere, had to drain the system, but didn't have drain valve, long story etc etc

I bought a new TRV valve and lockshield - I have fitted both of these onto the relevant pipes where I removed the radiator. I have refilled the system and no leaks - so far so good.

Now what I thought would be the easy bit - I have gone to fasten the rad onto the valves - but have found that the rad nuts are too big for the TRV???

The TRV has compression fitting on the output to radiator which I am guessing the bit of pipe with thread on one end fastens into - then the radiator should fasten onto that? But the rad nut does not fit the thread??

I have scoured the internet and have not found many people with same problem so I am either missing something very easy or it's not very common!

The radiators were fitted in about 1970 and are just one column flat rectangular - not like the two pieces of flat rectangle ones you get today (if you understand what I mean!?)

Sorry if this comes across as daft!

 

[rjm2k]

Post a photo if you can, many TRVs come with a replacement tail. You normally take the existing tail off the rad (using a "radiator spanner" which looks like an allen key), put the new tail in and then the TRV connects to the new tail via a compression fitting. In the image below, the threaded bit on the left is the tail which screws into the rad, the trv has a compression nut which fits onto the tail.

 

[aaron1987]

thanks for the quick reply.

I bought this trv

http://www.toolstation.com/shop/Hea...+Lockshield+10+15mm+Angled/d230/sd2762/p25331

But this link shows more of the bits I got in the pack

http://www.toolstation.com/shop/Hea...Angled+TRV+with+Lockshield/d230/sd2762/p49314

I dont think any of those bits are the radiator tail?

Your picture looks similar to what I have - a piece of pipe with a thread on one end - which I am guessing the pipe tightens to the locking nut on the trv and then the thread is where the rad fastens too.

Where could I get radiator tails from if they are not in the pack I have linked to above? The trv valve pack I have says it was 10mm and 15mm - I have 15mm pipe

Not sure what info is helpful for you all here so I feel like i'm rambling a bit! lol

 

[aaron1987]

Now I feel a bit daft !

Is the piece on the left of your picture the radiator tail? I screw the thread into the radiator. Then I connect to the new valves via a compression fitting??
I was expecting to have a screw on type nut for radiator?

 

[Burnerman]

On the second pic, those tails when fitted give you a little extra adjustment if the rad is a fraction smaller than the one you may have removed.....use the first pictured ones, using the new tail (plenty of turns of ptfe tape and some sealant for good measure - screw 'em in real tight).
John

 

[rjm2k]

Yep, that's correct. The old tail will have screwed onto the old valve. You will need to remove this old tail from the rad, screw the new tail into the rad and then use the compression to attach the trv to the new tail. make sure you use plenty of tape when you screw the new tail in.

 

[aaron1987]

Thank you for your help!!

I should be able to get the radiator back on.

It's quite an embarrassing feeling when you consider yourself as a good diyer and do all your own work - then can't figure out how to get a radiator on!!!!!

 

[longdogs]

Thank you for your help!!

I should be able to get the radiator back on.

It's quite an embarrassing feeling when you consider yourself as a good diyer and do all your own work - then can't figure out how to get a radiator on!!!!!

We all need advice now and then

 

[aaron1987]

one last question?

can someone tell me (if radiators spanners are a standard size) what size allen key fits the radiator tails?

I can bring one home from work with me then and do it tonight.

 

[Burnerman]

I'm pretty sure its the old 1/2" size, but a 13mm one should be fine.
The 'plumbers tools' one from B&Q is actually 12.64mm
John

 

[onecog]

I'm pretty sure its the old 1/2" size, but a 13mm one should be fine.
The 'plumbers tools' one from B&Q is actually 12.64mm
John

Or when you can't find the hex spanner a 1/2" wood chisel fits neatly inside and a pair of grips to twist

 

[aaron1987]

I'm pretty sure its the old 1/2" size, but a 13mm one should be fine.
The 'plumbers tools' one from B&Q is actually 12.64mm
John

Or when you can't find the hex spanner a 1/2" wood chisel fits neatly inside and a pair of grips to twist

I think the wood chisel option is looking good! lol

I have seen this http://www.toolstation.com/shop/Hand+Tools/Plumbers+Tools/Radiator+Hex+Key/d10/sd210/p26053

Is this the tool I am after - pictures are deceiving as this looks far too small if I need it to be a 13mm or (12.64mm lol) allen key?

 

[onecog]

That looks the one though mine is about 20 years old and looks a bit worse for wear.