Chris French wrote:

I've tested the solenoid resistance on the left with my cheapo multimeter at it
is showing open circuit , so has presumably failed. Are there any other checks
I should do?.

Or is that pretty conclusive?

Sounds it.

I don't know much about the gas valves, does the
solenoid control the flow of gas to the pilot as well?

Mine's a permanent pilot, and yes the solenoid valve supplies it
(controlled by thermocouple) ... hope my gas valve keeps hanging on in
there ...