I have a raypack 135b gas boiler that the flame goes off like clock work every night. I have replaced therma couple dozens of times, checked,cleaned,replaced exhaust piping, removed and cleaned all burners,replaced pilot line and pilot,bypassed sensors and replaced every thing I can think of except the Robertshaw Gas valve. Boiler works fine but every morning the funnace is off with cold pipes again!! What am doing wrong? Should i replace the gas valve or get a complete new boiler system?