Renewing a gas system

Bodach na mara

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(A short diatribe on conflicting, misleading and plain bad advice and suppliers as compared with chocolate teapots.)

I had decided to renew the components in the gas system (something to do with an impending survey!) as all the bits are past the recommended design life. That is 5 years (from date of manufacture) for hoses and 10 years for the regulator. The resulting experiences are driving me daft.

The system has two "pigtails" from the cylinders to a wall block manifold, which incorporates non-return valves. The regulator is fixed to the wall block with a standard cylinder nut-type connector and to the pipework with a compression coupling. There is a single run of copper tube to the valve below the cooker and the final link is an armoured flexible tube connected by compression couplings. All exactly as advised in the Calor instructions when it was installed over ten years ago. The tubing is stamped as madde in 1998 and the regulator in 1974. And I thought I had renewed it!

First the pigtails and armoured flexible tube. The chandlery at the marina has them in stock, BUT they are stamped as manufactured in May 2006, i.e. they are nearly three years old already. With only 40% of design life left, will I get them at 60% off? No chance!

Off to the Calor shop in Glasgow. "Sorry sir, we do not carry flexible armoured connectors and we do not have any pigtails in stock." They did suggest removing the crimp connectors from the pigtail ends, removing the old end fittings and making new pigtails with high pressure tubing (£1.78 per metre), which they did have in stock. I asked how the tubing should be secured and was told "use a Jubilee clip." They do not sell any regulators suitable for connection to the pipe to the cooker with a compression fitting, only those with an 8mm connector suitable for a rubber hose. There next sales pitch was to suggest that I change over to propane, assuring me that the cooker would "probably" work ok! Er, no thanks!

When I got home, I checked and found that the tubing they had sold me is stamped 04/2007 (nearly 2 years old) and that you must NOT use Jubilee clips on this size of tubing.

On to the internet and Calor Marine web site. I also looked at the main Calor site. The same regulator (rubber tube outlet connector) is available on both sites. On the Marine site, the regulator costs £10. On the main site it costs £5.87. (It is available from an on-line chandlery for under £4.)

I have sort of decided to get a marine regulator from the Calor Marine site. I draw the line at the £40 stainless steel job as the type of outlet is not stated and there is a confusing list of inlet fittings to chose from, but there is one with a 3/8 in BSPF outlet. I did not like the idea of a rubber tube connection between the regulator and the tube to the cooker. I would have bought the pigtails and armoured tube there as well, but they do not carry the correct length of armoured tube and the pigtails are twice the price in the local chandlery.
 
I'd suggest removing the parts you want to replace, measuring them with a vernier to check the pipe sizes and calling http://www.calormarineshop.co.uk/. All the bits you're describing are standard. Make sure you know the copper pipe diameter - I think there are metric and imperial sizes that are very similar. I have a single pigtail so no non-return valve. Do these have an expiry date?

BTW the modern armoured pigtails are heavier and tend to snag under the cooker. A plastic clip fixed this on mine.

This is mine before replacement:
gas_bottle.jpg
 
Thanks Rob, I did know all the sizes before I went a'hunting. The pigtail is the bit between the cylinder and your regulator and has a life of five years from the date marked on the tubing. The date on the armoured tube is stamped on one end crime. As it is rubber inside the armoour, these are subject to a five year life as well.

From the photo, I would suggest that you may be due a new regulator as well as me. and you will find it expensive to get one to fit the 3/8" BSP female thread on the elbow on the outlet.
 
had similar problems a couple of years ago and after much gnashing of teeth, ripped the lot out and put a Taylor's paraffin system in instead!
 
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This is mine before replacement:
gas_bottle.jpg


[/ QUOTE ]Please tell us you put proper high pressure hose on the bottle side?

I really don't understand the fashion of keeping the regulator off bottle on boat installations, that 'hose' even if correct type is just too frightening for me.

Your installation does kind of show why DIY installations are frowned upon, no wonder you changed it. I did mine myself, but read half an encyclopaedia beforehand.

Many apologies if the image shows the installation you fitted, I am honestly not trying to be offensive.
 
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From the photo, I would suggest that you may be due a new regulator as well as me. and you will find it expensive to get one to fit the 3/8" BSP female thread on the elbow on the outlet.

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Photo is before replacement.
According to my scruffy notebook top elbow is 3/8 and the pig tail is 1/4".
The regulator was £11 and the pig tail £12. So not expensive.
Apparently the bits came from www.chandleryworld.co.uk/ .
I never did get a bubble detector. Couldn't find a 3/8" one for a reasonable price.

... and the job was on the list of things to do for three years before I got round to it /forums/images/graemlins/shocked.gif
 
Thanks for the link Rob. Sorry I did not notice the text above the photo "before replacement." That is the problem with speed reading, Too much speed, not enough reading.

By the way Dogwatch, current advice on the Calor Marine site and the BSS is that the regulator should NOT be bottle-mounted, as removal to a wall block makes it less likely that liquid gas could get to the regulator. The pigtail must be HP rubber tube of length less than 1 metre.
 
Have a look at Gaslow. They do all-stainless high pressure connections from butane or propane bottles to a bulkhead regulator. These have an indefinite life (or nearly) and avoid the much publicised problem of rubber products getting into the regulator.
 
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By the way Dogwatch, current advice on the Calor Marine site and the BSS is that the regulator should NOT be bottle-mounted, as removal to a wall block makes it less likely that liquid gas could get to the regulator. The pigtail must be HP rubber tube of length less than 1 metre.

[/ QUOTE ] Fair enough.. I presume this is for the problems associated with 'tippy' boats. My bottles are locked down and if they get to an angle where this may be a problem we certainly will not be cooking and in honesty, the regulator filling with liquid might be the least of our problems. We always turn off at sea (except when cooking), but I will seek advice on this as I have never heard of that before.

I also like the fact I can quickly change over regulators for prop / butane and in the future possibly camping gaz. Thank you for the heads up.
 
A couple of years ago I replaced my complete gas system myself using the Boat Safety Scheme guidelines. I bought most items from the Calor Shop except for the copper tubing which came from Plumb Centre stamped with the appropriate BS number (BS EN 1057) where it was much cheaper. I also bought a mini pipe bending tool which proved its worth even if only for one bend.

Like you, I found the range of fitting sizes complicated and as I already had a gas solenoid valve and a bubbler to fit, I was stuck with those sized fittings. The bulkhead Euro regulator (suitable for both butane and propane) available from the Calor Shop had the wrong sized exit to match up with my solenoid. I phoned them and they gave a lot of useful advice. They also supplied the Euro regulator with a different sized exit fitting which then matched my solenoid.

I made up a ply board with the regulator, solenoid and bubbler attached. I had to use different thickness backing pads of ply to get them to all line up in a straight line. With everything pre-mounted on the board, it was easy to mount it all in the locker and connect to the bottle at one end and a bulkhead fitting at the other. A single length of suitably secured copper pipe was led to a shut off tap near the cooker and a flexible hose went from there to the hob.

I haven't had a survey since but I hope it comes up to scratch. A picture of the locker arrangement is shown below. The bottle has not yet been secured and the cockpit speaker is disconnected and waiting to be removed. My surveyor was happy for the gas locker to drain into the cockpit because one of the three drains is above the waterline and the main cabin access has a bridgedeck which is higher than the cockpit sides!

IMG_1731-1.jpg
 
I'm not quite sure what you mean but the valve just connects directly between the two pipes with the supplied fittings. Any sealing of the link between the valve part itself and the gas is all built in to the unit. My valve is part of the Pilot Gas Monitoring System so the valve can be shut off manually as well as by a gas leak triggering via the sensors.
 
Nice neat arrangement. In response to another post on this thread, the hole through which the cable for the shut-off valve passes will need sealed against the slight possibility that gas could leak through it into the rest of the boat.
 
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Out of interest, why did you decide to put the bubble tester after the solenoid valve?

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That was the recommended way to do it. I can't remember where I read it but the solenoid had to be first. I can see your point that the bubble tester won't check for leaks upstream but on the other hand, with the solenoid as the first item this reduces the potential leak points between the solenoid and the bottle.

I only use the solenoid manually to switch off between meal courses and always turn the gas off at the bottle after I have finished cooking.

One advantage of the solenoid is that when I turn the batteries off, the solenoid closes anyway so if I ever do forget to turn the bottle off when leaving the boat, the solenoid will be off anyway.
 
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the hole through which the cable for the shut-off valve passes will need sealed against the slight possibility that gas could leak through it into the rest of the boat

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Ah. I see what he means.

The cable is through a tight fitting hole ABOVE the top of the bottle and has been sealed with a silicone sealant both sides. The screw holes fixing the ply board have also been sealed.

Edit: I've just checked the Boat Safety Scheme requirements and the locker only needs to be sealed up to the level of the top of the bottle and regulator so technically I wouldn't need to seal the hole the cable passes through as long as the boat doesn't heel. /forums/images/graemlins/wink.gif
 
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Out of interest, why did you decide to put the bubble tester after the solenoid valve?

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I've found the advice here in section 6.2 of 'Best Practice Calor Gas Installation'.
 
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Out of interest, why did you decide to put the bubble tester after the solenoid valve?

[/ QUOTE ]

I've found the advice here in section 6.2 of 'Best Practice Calor Gas Installation'.

[/ QUOTE ]I'd interpreted the Boat Safety Scheme as intending that a bubble tester should be next after the regulator (see page 4). It seems fairly pointless having a bubble leak tester upstream of a potential leakage point.
 
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It seems fairly pointless having a bubble leak tester upstream of a potential leakage point.

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I think you must mean downstream.
 
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