Why would the pilot light keep going out on Smith GB100W Natural Gas Boiler?

Good Morning,

Yesterday morning we woke to no heat after installing a brand new heater (replaced twice in two years due to floods). Since yesterday we have been going down into the basement and relighting the pilot light every 40 minutes as well as trying to fix the problem.

The Rollout Switch, High Limit Switch and Spill Switch are operating correctly, we have tested for carbon monoxide and it has no filter.

However the Gas Valve seems to be missing a screw on the intake side (we can't find it). Can you think of anything else that could be causing this?

Thank You
Cindy-lu
email: sar883@hotmail.com

(Model VR8200 or VR8300)