looks, exactly like the vokera compact 24 inside, same H/E 10021419. mains pressure big problem with these anything over 6bar reduces life expectancy. Like tony says gas/press need checking.
If it's locking out to solid red light then its probally the primary thermistor 10027352 if it won't ignite and as a flashing green light then it could be the venturi 01005405.
please help me! in each pack i have 1@1200 long 4@900 long 3@700 long-3@500long and 4@300long all these make a 1200-but with only one at 1200 i can't seem to get them to look right when laying them?