Gas pipe fitting

[Walrus]

I've fitted a propex & a cooker to my van but need some advice regarding the pipework. I have read that I should connect it all with solid copper pipes and only have a rubber hose (from a 3-way mainfold) to the gas bottle.I cant use one continuous length of pipe from the appliances to the manifold because the existing engine LPG tank is in the way and the access hatch to it is too small to be able to thread the pipe around all the bends.

I'd like to use compression fittings to make up the joints and connections. I have no problem doing it myself and will test everything thouroghly before lighting anything! Should I use anything on the compression joints to help them seal?

I would also like to use a 3-way manifold so I have a spare connection for future expansion if I decide to fit a 3-way fridge. Will this be ok to just leave the spare outlet tap in the 'off' position, or should it be capped?

Thanks in advance!

[lloydy]

you can use jointing compound, when you buy it check its suitable for lpg. The unused port on manifold should be capped off. Dont overtighten the compression joints, 8mm copper is soft and will deform
lloyd

[bigherb]

Definitely no rubber pipes to the appliances unless they are portable. You can use sealing compound or gas PTFE tape, Calor gas do a sealing compound that looks pretty much like red Hermatite. Definitely cap the spare outlet especially if they are the overcentre type taps, it's very easy to knock the lever on.

[MattyG]

Hi

sorry to jump on your thread!

what thickness pipes are you using?
does it need to be certified by anyone?
Im trying to find out a bit more info on hard piping my van but cant find much available?

cheers
matt

[Walrus]

I've finally got all the bits together I want:
8mm copper tubing (got a 10m reel), lots of compression joints, 2-way manifold (for heater & cooker - there is a spare in-line outlet for future expansion), joint sealer, leak detecter (spray). All pipes to run internally (nothing on the underside of the van), fixed at regular intervals with 8mm pipe clips.
The long-term plan is to get a LPG tank fixed where the spare wheel goes so I'm making the gas bottle connector accessable for fixing to a permanant tank.

No certifications required AFAIK, but if your van burns because of your dodgy gas fitting I'd expect the insurance company to quibble over paying out!

[MattyG]

thanks Walrus

i just want to fit it to a standard 5kg (think thats the size? fits in the bottom cupboard of a Devon?)
How would I connect to the gas bottle if its hard piped?
Would the last section be standard 8mm flexi hose?

cheers

Matt

[Walrus]

Yes, the bit from the bottles regulator is a short length of hose. I've bought a proper'barb'to fit the hose onto at the van end.

[jamesandtheopenroad]

Hi
Just taken mine all apart to rust treat the panel behind the kitchen and noted the red sealant on the gas pipe connectors.

Can I ask you where did you get yours from and what's its name?

[Walrus]

This stuff: http://www.screwfix.com/prods/30469/Plu ... d-PTFE-50g - suitable for LPG.

[pierce]

When I did my instrumentation apprenticeship a while back, we were taught that ptfe was only to be used on tapered threads, compression fittings were designed to seal on the olive. A job would not pass inspection if it was seen.
i have never worked with gas, but would imagine it would be the same, have a read up before you use it.

[Walrus]

Opinions seem to be divided on the forum about 50/50, so I'm going for the belts & braces approach.

[pierce]

Opinions seem to be divided on the forum about 50/50, so I'm going for the belts & braces approach.

Ok cool, sure a bit of a bit of compound ptfe over the olive, will be ok. But obviously keep it off the threads, you could always read the manufactures suggestions from their website to be doubley sure

[DentedDevon]

When I did my instrumentation apprenticeship a while back, we were taught that ptfe was only to be used on tapered threads, compression fittings were designed to seal on the olive. A job would not pass inspection if it was seen

100% correct for LPG as well.
PTFE for taper thread joints only.
Compression joints , the olive IS the seal , so no sealing compound should be needed.
Copper olives are best on copper pipe because they are softest, Brass olives can be more difficult to get a good seal with.
Joints on chrome plated gas taps are a regular place for leaks , I think due to the chrome .
Jointing compounds (& PTFE tape) as said must be approved for LPG.
In my daily work jointing compound usually indicates a joint where there are problems !

[kentishvanman]

Hi,
Calor Gas web site , Marine sect. I think, gives full instructions about gas fitting etc.
I think its on there that you don't/shouldn't use sealing compound. Nothing but the fittings.
I have replaced my gas work and never used compound. Don't overtighten.
It used to be that you tested everything with washing up liquid. Nowdays 'they' say that w/u liquid contains salts that corrodes the pipes so use Gas Detection Fluid.
Don

[Bamba]

No Jointing compound or PTFE is to be used on 'new' compression fittings, it is also advised that copper & not brass olives are used as the tourer industry has stopped using them on caravans/campers etc in the last couple of years as the movement of the vehicle/pipework can cause a gas escape from fittings with brass olives & as no-one carries out a gas tightness test after every journey its recommended that copper olives are used. When tightening up a compression fitting especially on soft copper pipe eg 8mm its hand tight then a quarter turn with a spanner, then test for leaks if it is leaking then tighten up a bit more then test etc this lessens the chance of over tightening & over crushing the olive & pipe.