Gas shut-off

I read or at least skimmed the Lord Trenchard report. Summarise as connection to bottle not done up properly, gas locker not gas tight. Gas alarm didn't go off.
The gas locker is your primary defence against failure of the bottle connection. The bottle connection is possibly the weakest link in the system, as it is the only connection that should be broken and remade in normal use, i.e. by anyone who happens to be using the boat. Any 'safety devices' downstream won't help wth this connection.
The gas locker needs to be properly sealed from the interior spaces of the boat, and properly vented to the great outdoors. This makes it a challenging environment for electromechanical devices such as solenoid valves, so any feeling of enhanced safety from a solenoid valve is quite likely false imho.
Also note the other thread on here re gas alarms, false alarms and unreliability seem to be commonplace. The maib report noted that the Lord Trendchard's gas detector had a self test function, which tested the electrics of the device, which was relied on rather than testing the whole device by exposing it to gas. This seems like a classic example of complication of safety arrangements missing the point. I don't own a gas sensor, but when I do I shall make arrangements to test it easily using a butane lighter. I don't know about the tendency to false alarms reported elsewhere, that could negate the whole point if the alarm gets ignored.
 
I have heard more than one BSS boat inspector comment that one of the biggest sources of gas leakage on a boat is the faulty sealing of the connection to the bottle which is regularly disturbed to change bottles and the same sealing washer used time and again. I believe the source of the gas leakage on Lord trenchard could have been something like this.

It seems an amazing number of folk do not realise that they get A SPARE SEALING WASHER every time they buy a calor refill and this new washer is inside the plastic cap on the bottle.

Just changing this washer would make a big difference especially on older boats when the locker venting may leave a bit to be desired.
 
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I have made some valve motors using a wind screen wiper motor

[/ QUOTE ] But dont use one from automatic wipers or it'll turn the gas on everytime it rains and off again when it stops!
<span style="color:white"> ................................................................ </span> /forums/images/graemlins/laugh.gif
 
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It seems an amazing number of folk do not realise that they get A SPARE SEALING WASHER every time they buy a calor refill and this new washer is inside the plastic cap on the bottle.

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I thought the propane cylinders had a conical metal-to-metal seal ? - Is this washer just for the 10lb butane cylinders?

Andy
 
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Is this washer just for the 10lb butane cylinders?

[/ QUOTE ] For Calor butane cylinders regardless of size.
When supplied they have a plastic cap screwed on the outlet. Inside the cap is a new sealing washer that can be transferred to the regulator fitting or hose end fitting as appropriate.

I have known about it for a while but I wish I had known about it a long time ago.

You are right about propane they have a conical metal to metal joint like industrial gas cylinders etc.
 
I thought the propane cylinders had a conical metal-to-metal seal ? - Is this washer just for the 10lb butane cylinders

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All butane calor cylinders where a washer is used...

The majority of these washers are thrown away with the plastic caps!!!
 
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For Calor butane cylinders regardless of size.
When supplied they have a plastic cap screwed on the outlet. Inside the cap is a new sealing washer that can be transferred to the regulator fitting or hose end fitting as appropriate.

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I think that's just the 10lb cylinders (4.5 kg??). AFAIK the larger butane cylinders (7.5 & 15kg ??) have 'quick connect' type valves, and a nasty orange cap held on with a piece of bent wire. Each bottle comes with its own washer, though /forums/images/graemlins/smile.gif

Andy
 
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I think that's just the 10lb cylinders (4.5 kg??).

[/ QUOTE ] Yes you are right . It is only the 4.5kg bottles. The larger ones do have the quick fit type of connector.

No variation with propane AFAIK.
 
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