Hints and Tips



Gas Safety

Butane Gas detection

After experiencing a very worrying leak from the pin hole, shown in top centre of the left picture above, in the standard Camping Gaz regulator (not the OEM Jeanneau fitting) , I decided to fit a gas detector system.


When I reported this potentially lethal fault to the UK importer of Camping Gaz - Coleman UK I was amazed by their lack of surprise or concern. They said it would appear the internal diaphragm had ruptured, which normally last for 6 to 7 years. when that happens apparently the regulator is designed to vent gas from the pin hole to alert the user there is a fault!


I would have hoped with real risks associated with gas in boats that any fault was designed to set to a failsafe a closed position.


The regulator was about four years old and had been kept dry, so I don't think the unit was exposed to anything but normal wear and tear. In future I will be replacing these every 2 seasons.


To choose a good marine alarm system the PBO article gas alarms tested was very helpful.


Based on the PBO recommendation I chose the waterproof 2 sensor Nereus system.

I fitted one sensor in the bilge area and the other in the top of the gas locker , with the control the unit in the galley next to the watertank gauge where it is accessible but protected. It is also a good location to connect power from the rear of the 12v electrical outlet and all wiring can be completely hidden as there is cover panel within the locker at the rear of the water tank gauge. On the downside the gas detector therefore is only on when the interior light circuit breaker is also on, but I felt that was acceptable as I always have this switched on when onboard.


Fitting was reasonably straight forward, but as with all wiring runs, quite fiddly to route the cables. I needed to extend the stand 6m cable for the aft sensor, by about 2m (surplus cut from the bilge sensor). You need a very fine jewellers screwdriver and a steady hand to connect the fine wires from the sensors.

The photos should be reasonably self explanatory. Note I had previously inserted an inspection plate in the top of the standard self draining SO34.2 to allow easier shut-off of the gas regulator. To give some physical protection to the sensor I mounted it in a circular wooden block made with a large hole saw.


To mount the bilge sensor I screwed an offcut of teak through the lip of the bilge inspection floor trap.


After fitting I tested both detectors by releasing a small bit of gas from a cigarette lighter close to them, quite reassuring how sensitive the Nereus alarm was.