Has anyone found a remedy to stop these blowing out when on gas? I have had the van from new (5 years) and it always seems to do it on one particuliar site, when it is really blowing hard. I think that I seem to recall that Truma or Carver could supply a sort of cowl that clipped on to the chimney top when conditions are bad - but it had to come down before travelling. Any ideas gratefully received.