Problem with new Boiler

MPL15654

I installed a Burnham IN-6 boiler today. Upon startup the boiler would run for 6-8 mins and then shut off, turn on shut off, turn on shut off repeatedly. I jumped out the T/Stat still happened. Jumped out Blocked Vent Switch, still happened. Jumped out flame rollout still happened. Jumped out Pressuretrol still happened. Bypassed the low water cut off and it still happened. The only thing it can be is the Vent Damper but i couldn't bypass it. Everytime this happens it will run for 6-8 mins perfectly fine and then this happens, i checked and i lose 24V to the gas valve and then it comes back when it retry's to light. Oh and also replaced the relay and the ignition control. I can't figure this out. Anyone have any ideas? It's a brand new boiler. It's not shutting off on low water or pressure, something is causing me to lose 24V to the gas valve when this happens but like i said withing seconds it comes back and retry's and this happens repeatedly, it will fire up then shut off. But like i said the boiler will run perfectly for 6-8 minutes before this happens.

Steamhead

Find out where you're losing the 24V

for starters, does the LWCO remain energized when you lose voltage to the gas valve? How about the ignition module? If these units lose power you could have a loose main power connection or a bad transformer. ISTR Burnham is now sourcing their transformers from China.............

MPL15654

LW Cutoff

Low Water Cut off remains energized, ignition control loses power. Like i said it's really strange, it works fine and then all of a sudden this happens and i check 24 V to gas valve and control, it loses it when it happens and then within seconds it gets power back and fires up, then shuts off right away, and continues that cycle, but as soon as i shut the switch it runs fine for 6 minutes or so before it starts all over. Thought for sure it was a bad safety causing me to lose 24 V but i can't think of anything else to troubleshoot and bypass other than the vent damper. Would a transformer have 24V all the time then just die for 3 seconds than get power back again? There's no issue with the power going into the boiler.

Steamhead

That's where I'd look next

then I'd check the power lead coming off the damper to the ignition module.