new radiator leaking

northernsoul

Hi
Just fitted an additional Kudox radiator. Copper pipe on show to radiator, connected to plastic fitting beneath floorboards. On assembling the tails into the radiator the 'thermostat' side tail screwed in and tightened as expected, with the tail thread just still visible (1mm) still sticking out of the rad. The 'lockshield' side tail thread screwed in and the end of the thread went 2/3mm inside the radiator thread (ie as if it was going to screw in and fall inside the radiator) before it got tight. Radiator valves were then connected. Because of this I probably did not tighten the lockshield tail enough because it now leaks (1 drop every 30 min).
Should it go in so far, is this right? I put 10 layers of PTFE on. Shall I release the valve off the tail and then tighten the tail further? Will I be able to tighten the tail with the olive on the tail? Will the olive seat correctly when I tighten the valve back on? Any advice will be appreciated.
Thanks in advance

Crinkmeister

I wouldn't try to tighten further without some additional sealing. If you can back the tail out halfway and add some more ptfe tape or ptfe string plus a little boss white or other pipe thread sealant if you have it then tighten back up. The olive seal should be ok as long as you didn't overtighten it. A little boss white or jet blue doesn't go amiss on compression joints. Emphasis on little! Good luck.

northernsoul

Thanks.
I think I can release the valve and persuade it back away enough from the radiator to allow the tail to be screwed out enough to put some more PTFE on. I might even be able to move the valve totally away and drop it down. If I can move the valve away would you advise taking the tail totally out ? (and back in with much more PTFE). Either way I guess the radiator water is going to come out.

northernsoul

do you recommend putting on Boss white and Jet Blue (never heard of them) even if I can get plenty PTFE on. Should have known to take tail out and put more PTFE on when it went in so far

southcoastrgi

It's a parallel thread not tapered therefore it's the ptfe tape that makes the seal you haven't put enough on

Crinkmeister

Boss white or jet blue - not both. Shouldn't need it IF you have enough ptfe on there, but sometimes the threads in the rad are a tad oversize, so they need more packing. Yes, your rad will probably lose its water, so have some containers ready.

northernsoul

Kudox instructions said at least 6 layers of PTFE, I put 10ish but obviously it seems this is not enough baaahh

northernsoul

Thankyou for your help.......experience !

Crinkmeister

northernsoul wrote: »

Kudox instructions said at least 6 layers of PTFE, I put 10ish but obviously it seems this is not enough baaahh

I have NEVER found 6 turns to be enough!

northernsoul

Update
Firstly thanks to everybody who gave advice. It is now all okay.
I managed to completely screw out the tail. The PTFE tape stayed on the thread in the radiator and I left I there (Should I have taken it out ? ). I put 15 layers of PTFE on the tail ( with 10 still inside the radiator thread). I screwed it in and it started to become tight then the tape stopped turning (up against the tape already in the radiator mybe ? ). I screwed it one more turn and the tail was sticking out of radiator about 3mm. With the 16mm pipe holes in the floorboards drilled from when the tail was 4mm inside the radiator, the holes were now out about 7mm. I chose to move the radiator and share the difference between both ends of rad. The result being now that at both sides the top tapers out about 3/4mm at the top ( ie not vertical ). Had a few leaks at first (not at the tail) but managed to tighten up enough to stop. Maybe I should have redrilled but I did not fancy drilling next to the pipe and maybe damaging the copper pipe and the plastic fitting 20mm below the floorboard.
By the way this was the first time I have used plastic fittings (Hep2o) and they were easy to use.

Crinkmeister

Sounds like you did ok!