Danfoss RAS-D2 8/10/15 TRV All aspects of plumbing questions and answers, help, tips and information

[27col]

Today I have been fitting a Danfoss RAS-D2 Combi 8/10/15 TRV, when I installed a new radiator in a different position. The size of the pipe used in the installation is 8mm. This is the first time that I have come across this particular type of valve.
If any of you knowledgeable types out there are familiar with this valve, perhaps you can tell me if the collar which forms the 8 mm olive reducer, is supposed to be soldered on to the pipe. I found that if it was not soldered, even when the chrome compression nut was done up really tight the 8mm pipe could still be swivelled by hand. There is no way it would have held water. In the end I soldered the ring with the 8mm taper adapter, on to the pipe. Now the pipe can be done up tight, so that it will not swivel. There are no instructions with the valve to indicate the correct assembly of these different adapters. Any informed comments would be much appreciated.

[plumbbob]

Not sure about that valve, but if the adapter is a compression

they are not designed to be soldered, and are completely useless and often leak. I always use a solder fitting.

[steviel]

I am looking at the 10mm reducer with the same thought - how does this grip the 10mm pipe, as the reducer is made of brass and no matter how tight you tighten the nut the pipe swivels by hand. HELP!!

[plumbbob]

If you Google tbsmerchants.co.uk and then search for Compression_Internal_Reducer_Set_15x8mm and if the reducer you describe looks like this then there should be a 10mm olive to grip the pipe.

Sometimes the fitting is supplied as a single piece, not three pieces and tightening the main 15mm nut cracks the parts so the 10mm olive can grip and seal the joint.

[steviel]

Thanks plumbbob. I fitted the radiator anyway and it seems to be fine. As you mentioned the reducer is a single piece.

Also emailed Danfoss and go the following reply:

If the pipe can be turned then the nut needs to be tightened further.

When this is done the brass reducer will crack along the groove. Part of it will compress the pipe and the other part will hold the pipe square in the valve.

:D