Atwood confort 3 water heater

[scottp]

I just bought a 1994 herald motorhome and it's working on mains but not on gas.
There's no instruction manual so I'm not sure what to do.
I turn it onto gas theres a strong single click in the gas area but there's no spark and the red fail light comes on. After a few times i can smell gas.
Can anyone help

 

[Figaro]

Sounds like there's an ignition unit fault if no spark.
Get it checked by a professional unless you know what you're doing, at 30 years old it could be in need of a service at the very least.
At worst it could be dangerous ?