Random Questions Part 3

[WaterTight]

Been a while since my last one. Like to accumulate them sometimes for a barrage.

1. Old school / experienced guys - what was the most recent thing you learnt about plumbing?

2. Why are there sometimes two, in-line, separate means of isolation on a filling loop?

3. Can you put the end of an end-feed drain-off into a compression fitting? Never tried it. Looks like there might not be enough of it.

4. I often dismantle pre-existing compression joints while working to find there is no ptfe at all round the olive and often the joint was barely tight. Most recently on a combi system under a rad. How has this not leaked? Did they use a jointing compound that has since evaporated? But wouldn't that the leak? Or is it actually not really necessary to use ptfe all the time?

 

[john.bell55]

3. No. Olive won't fit
4. PTFE Not neccessary. You should not overtighten compression fittings. From your post it looks that you might do. No magic disappearing jointing compound either

 

[WaterTight]

I've been copying the two guys I've work for and put ptfe on every single compression joint. Between them they must have 40 years experience. Maybe it just becomes habbit when you get a few leaks and get annoyed.

 

[john.bell55]

There's nothing wrong with this practice. It reassures some that the joint will be good. But as I say, not neccessary.
Copper olive usually better than brass ones. IMHO

 

[Robtheplumb]

Been a while since my last one. Like to accumulate them sometimes for a barrage.

1. Old school / experienced guys - what was the most recent thing you learnt about plumbing?

2. Why are there sometimes two, in-line, separate means of isolation on a filling loop?

3. Can you put the end of an end-feed drain-off into a compression fitting? Never tried it. Looks like there might not be enough of it.

4. I often dismantle pre-existing compression joints while working to find there is no ptfe at all round the olive and often the joint was barely tight. Most recently on a combi system under a rad. How has this not leaked? Did they use a jointing compound that has since evaporated? But wouldn't that the leak? Or is it actually not really necessary to use ptfe all the time?

1.Can't think at the moment, but I'm not that Old school
2.Just the way some are.
3.I have done this in the past without any problems, looks bad though
4.You "shouldn't" need anything on a compression fitting, however a lot of people use a compound of some sort or ptfe tape

 

[tamz]

1. Can't think of anything recent but even old heads learn snippets of new stuff all the time . Possibly don't fit another Vokera. They are shyte. Learned that one last week.
Easier to answer the 1st thing i learned about gas. Don't cut a 4" unpurged gas pipe with an oxy acetylene cutting torch (its a long story involving a scaffold a hacksaw and an smartarsed apprentice )
2. Don't know but if someone comes up with the answer then then i have learned something new so that would answer question 1.
3. Whatever turns you on. It will seal ok.
4. As above but tape or compound is not necessary but sometimes it gives a bit reassurance. Biggest pet hate is ptfe ( btw it stands for polytetraflouroethylene, the second most friction free material known. Wonderful stuff really) around the threads especially when done by a so called professional.

 

[buff]

ptfe on olives is a "comfort blanket" i some times do it
ptfe on threads only damages the thread,the thread is designed to lock into each other therefore putting something in between the threads makes them less likely to engage and lock
bob

 

[steadyon]

1. Don't trust plastic adaptors. Had one on inlet to WC. Split with invisible, hairline, split. Only let water out at night when pressure went up and flooded bathroom floor.

2. So that you can disconnect the filling loop, as we all do.

3. You can get ones with longer spigots, meant for push fit but work OK with compression.

4. You don't need it on new fittings in good clean condition. If re-using an olive it doesn't do any harm. Round the threads is pointless for leak sealing, but some think it reduces the thread friction. Personally think it just looks ugly.

 

[Billy Bob Bob]

1.cant remember
2.water regs
3.yes it does work
4.luck

 

[justlead1]

The most recent thing you learnt about plumbing. Is the liberties i would have took if plastic pipe and fitting were available at my peak.

 

[tamz]

The most recent thing you learnt about plumbing. Is the liberties i would have took if plastic pipe and fitting were available at my peak.

I have to agree with that one

 

[Bernie2]

I do like PTFE on compression fittings. I think the white tape makes for a fetching colour contrast with the brown copper!!!

Basically both ptfe and jointing compound is/was intended to act as a cushion between the two bare metal machine faces of the ring/olive and the body of the fitting. I think Conex get a bit upset though, if you mention that you need any jointing at all.
I think they pride themselves on the quality of their machining. So you can use their fittings without jointing.

Personally I always use Bosblue, except where there is a danger of stray bits getting into the likes of showers, filters or combi change over valves. But if your careful its okay. I suppose its habit really from the days of Boswhite.

 

[tamz]

Ahhh

Bosswhite. Plumbers perfume. Kills the smell of any other perfume. Wee dab behind the ears on the way home and Bobs your uncle