I’ve got a shower on a gravity fed system with a good pump to boost the pressure.

The copper pipework in the airing cupboard (hot and cold water supplies) have been fitted with plastic push fit fittings which doesn’t feel right. In fact there are two showers feeding off the airing cupboard so the pipework in there is a bit of a maze.

I’m keen to avoid paying to get a proper job done (I know) so I’m thing about replacing the plastic with compression elbows. Is it worth me doing this?

Also one of the pipes is not quite aligned right and has been ‘forced’ over a couple of cm to align to the shower (I noticed this when I disconnected the shower to fit a new gasket and it made me worry about those plastic push fits getting lateral pressure). Is there an easy way to shift a copper pipe across a bit…like putting a slight kink/curve in one?

paying to get a proper job done

Kinda made your own point there 😉

Is there an easy way to shift a copper pipe across a bit…like putting a slight kink/curve in one?

Not without making the pipe shorter.

If there are no issues with leaks / pressure drops I would leave well alone. Otherwise…. get an actual plumber.

Moving from a system thats working perfectly . Introducing faults for no reason other than it doesnt feel right. Absolutely nowt wrong with push fit.

Ive had more issues with poorly soldered solder joints than with push fit. All my down stairs i fitted in push fit. Upstairs i left alone in previous owners soldered copper – leaks all been up stairs

Moving from a system thats working perfectly . Introducing faults for no reason other than it doesnt feel right

isn’t that what DIY was invented for? 🙂

Push-fit is the standard now is it not?

If it’s not broke, don’t fix it… Leave well alone unless you’ve got leaks or other issues.

You will probably end up with more problems fitting copper pipe with brass compression fittings than plastic push fit will ever give you.

If you do need a bit of a joggle in copper it is possible with a pipe bender or if doing DIY one of these: http://www.toolstation.com/shop/Plumbing/d20/Flexible+Connectors/sd2807/Flexible+Stainless+Steel+Hose/p16172

I’m a fan of using braided flexible hoses on taps and toilets as they make like a lot easier for the DIYer and look quite neat if they are visible. You can get ones with built in service vavles and in compression or push fit. I generally go with the basic type and fit a nickel full bore service valve.

The braided ones may not be ideal for a shower due to bore restriction though.

You really want the pipe run into push fit nice and straight, as you do with any fitting really. You can soften and bend the pipe with a hairdrier if you are careful not to overheat it (hence me not saying a heat gun unless you have a nice temp controlled one) and don’t let it crease.

Oh and if you do use brass compression on copper then get some of the Fernox sealant (the potable water version).

LISTEN TO THEM ^^^^^^^^^

blimy .. as i live and breathe.. rushing out to city plumbing to see what hairdryers they stock.. and in what colours.. what wattage is best for pipe bending and which curley attachments etc should i use..?

Maybe the hairdryer introduces a perm-anent bend?

Would you not be better with some 80s style curlers to put a curve in ?

HAIRDRIER ! ON COPPER PIPE ! 😯

I’m keen to avoid paying to get a proper job done (I know) so I’m thing about replacing the plastic with compression elbows. Is it worth me doing this?

No. Not at all.

Nothing wrong with plastic fittings on copper, nothing at all.

You will make it far worse if you try to “fix” it with compression fittings.

You can soften and bend the pipe with a hairdrier…

Genuinely LOL’d at that one 🙂

I presume they mean plastic pipe?

i hope not picton.

Hot water temp is to be set about 60 degrees C

googlefoo says your hairdriers commonly about 60 degrees C ….

Last i checked none of my plastic fittings went squiggling when i ran hot water through them.

a heat gun on the other hand can do up to 500degrees C……

plumbers blow torch – 1600degrees C

Hot water temp is to be set about 60 degrees C

And central heating normally hotter than that (early 80’s ish?)

JG Speedfit pipe and fittings are fine well over 100 degrees.

Of course I am talking plastic pipe and yes it can help.

Look up the thermal data (Tg, melting point etc) and modulus data for typical plastic pipe materials like polybutylene (PB). Cross linked materials are a bit different due to the chemistry but they will benefit, especially as at room temp they can be very stiff.

I suggested a hair drier for a reason, manufacturer guidance will be generally aimed at people with hot air guns and blow torches in their toolkits so advice is to not use any heat but you know that by not exceeding the in service temp you are also not going to do any damage. If it’s a short length you can also submerge it in hot water. If you look at the max pressure-temp ratings of cold vs hot water you will see a massive difference (4x) between the 20 degC pressure and the 105 degC pressure (normal max temp rating for these things). This is purely down to the difference in the mechanical properties over that 85 degrees.

Note that general guidelines state to not put plastic pipe within a metre of a boiler and IIRC not to use it at all with a solid fuel system as the temps may not be as well controlled.

If you want to see another effect of heat on plastic pipes look at how it expands lengthways when you run hot water through it. If you have a piece of pipe clamped at say 2ft intervals and constrained at each end then it will snake between the fixings due to the lengthways thermal expansion.

Use heat at your own risk and only low levels and to help with slight bends as you could de-laminate any wall structure but it does help.

JG Speedfit pipe and fittings are fine well over 100 degrees.

depends how you define “well over”.

copied from the JG website for their PEX:

Working temperatures and pressures

Application Usual working temperature,°C Maximum working temperature,°C Maximum working pressure, bar
Cold Water (indirect and direct mains) 20 20 12
Central Heating 82 105, short term malfunction at 114 3
Hot Water (including unvented cylinders) 65 95 6

105 I would say is a touch over 100. 114 is short term only.

depends how you define “well over”.

Working from memory from when I installed the stuff every day, I thought the max temp was about 120.

As it seems, it’s only 114.

Hey ho, My memory wasn’t far off.

Anyway, it certainly did read as if you were answering the question ….

…Is there an easy way to shift a copper pipe across a bit…like putting a slight kink/curve in one?

As nobody had asked a question about bending plastic pipe.

And you never mentioned plastic pipe, and your advice in the post was all regarding bending copper pipe.