the fridge will switch itself over to gas if you stop for fuel within a few minutes of switching your engine off. Then spark spark spark
not good if any petrol vapor is nearby
20 minutes is not a long delay for the missis (or for me for that matter when needing a pee and a coffee) when we stop upModern AES have a long delay (15-20 mins) before switching to gas (spark spark) for this very reason.
For most MoHos a greater danger is when refilling with LPG
20 minutes is not a long delay for the missis (or for me for that matter when needing a pee and a coffee) when we stop up
safety first.. I always turn the gas off when travelling
no point in having it turned on really while on the road..
But diesel heaters still require a spark to ignite the fuel vapour. In fact they emit a constant stream of sparks, as fast as a bee going buzzzzzzzzzzzzzzzzz. And they emit this constant stream of sparks even when they are running because the flame won't ignite the next pulse of fuel being injected. Of course the spark would have to be in the vicinity of the escaping gas and once the gas is sufficiently diluted by the air, it won't ignite. So for a kaboom the gas escape would have to be pretty close to the fridge or the diesel heater. Actually thinking about it, the escaping gas could conceivably be sucked in by a Truma combi trying to light, with more sparks and kabooms. Better to just turn off all appliances. And I must repeat that to myself, I am guilty of regassing without having turned everything off.My Thetford fridge delays for 15 minutes after engine switch off before reverting to gas. This is specifically to allow time to refuel.
However with a diesel powered vehicle there is no risk, though there is still potential from vapour emanating from nearby petrol-fuelled vehicles that are refilling of course.
If you have a suitable high flow rate cut off valve fitted in your gas installation it is not necessary to turn off the gas whilst travelling.
My GasIt refillable tanks are fitted with such a device.