Baxi Bermuda inset 3 50/6?

Hello.

I have a Baxi Bermuda inset 3 50/6. The stat and Timer calls for heat. The Pilot ignition creates a spark but the pilot fails to light. The Gas Valve has been changed but still the same. When the valve opens there is no gas coming out from the pilot. So I undid the pipe at the valve to the pilot and the gas came out so the valve is good and I checked the pipe is not blocked. Is the pilot A.S.D assembly faulty? How can I check/test.

Thanks Paul