15mm to 1/2 Inch Irish. Compression fittings on Qual Plex pipe

Battery99

I'm moving a couple of radiators in the house , and would be very gratefull if I could get some answers to the following questions.

1. The origonal central heating pipework is 15mm plastic (Hep2o I think) . Is it Ok to join this to 1/2 inch irish qualplex by using a compression fitting and inserts with a 15 mm olive on one side and a 1/2 inch olive on the other ? .

2. Is it Ok to use 1/2 inch compression fittings with 1/2 inch qualplex with the hard plastic inserts, or should I use push fitings . ( i've already got the compression fittings.)

Thanks.

311

The compression fittings are fine.
When you compress the irish nut and ring inside the metric fittings ,undo the fitting and wrap ptfe around the compressed ring ,then tighten it back up again.

Sometimes the fittings can be loose when you match 1/2 inch to metric ,but the tape always seals it properly.

Battery99

Thanks a million 311.

Could I also ask you ( or anybody else with plumbing experience)


1. The 15mm Compression fittings that I have seem to have a thin copper olive , while the 1/2 inch fittings seem to have a wider Brass ? olive .( Its wider by approx 2mm) Are these interchangable , i.e. will using the wider olive cause a problem in that the nut won't go on as far ?

2. Is it OK to use copper and brass olives ,at all, on qualplex pipe , I saw teflon olives mentioned somewhere

3. When using the standard 1/2 inch fittings with there origonal olives , is it a good idea to use some PTFE tape or that plumbers putty ? on the olive ,just to ensure it seals , or is it best to leave it alone?

4. When dealing with Metric and imperial (Engish/Irish) fittings are the threads on them the the same i.e. Are the nuts interchangable ( they seem to be ) ?, would have taught a metric fitting would have a metric thread, imperial fitting an imerial thread !

Sorry for all the questions, its all a bit confusing

Thanks.

bibibobo

Battery99 wrote: »

Thanks a million 311.

Could I also ask you ( or anybody else with plumbing experience)


1. The 15mm Compression fittings that I have seem to have a thin copper olive , while the 1/2 inch fittings seem to have a wider Brass ? olive .( Its wider by approx 2mm) Are these interchangable , i.e. will using the wider olive cause a problem in that the nut won't go on as far ?

2. Is it OK to use copper and brass olives ,at all, on qualplex pipe , I saw teflon olives mentioned somewhere

3. When using the standard 1/2 inch fittings with there origonal olives , is it a good idea to use some PTFE tape or that plumbers putty ? on the olive ,just to ensure it seals , or is it best to leave it alone?

4. When dealing with Metric and imperial (Engish/Irish) fittings are the threads on them the the same i.e. Are the nuts interchangable ( they seem to be ) ?, would have taught a metric fitting would have a metric thread, imperial fitting an imerial thread !

Sorry for all the questions, its all a bit confusing

Thanks.

1. not sure if these are interchangeable. i just use standard 1/2" brass olives on both qualpex and copper pipe.

2. never heard of a teflon olive. i replumbed much of my house with mainly qualpex for cable runs using brass compression fittings and brass olives. I used copper for the short vertical runs out of the subfloor and into the rad. looks a bit better than qualpex and can take an accidental kick better.

3. just use olives only. this provides the seal by compression down onto the pipe and into the elbow socket. be sure to use pipe inserts i prefer copper ones as they are thinner than the plastic ones therefore less restriction in the pipe. do not use any boss white putty. this is only for sealing threaded bars into rads etc.

4. never had a problem interchanging them although i did have the same queries as yourself when i started my project.

enmac

this article should help......