I have an issue with the air relief valve releasing copious amounts of steam for 30 minutes with the heater cycling through a on off cycle throughout the whole ordeal. This has never happened before and I am curious... is this normal? What should I be concerned about. What can be causing this to happen?
Our heater is a summer/winter hook up low pressure boiler made by Burnham Hydronics Inc. Model V13R-TB installed in 2008. We just had the Aqua-stat changed about three(3) weeks ago. We had to replaced the older heater when the coil flange failed and the heater leaked into the kitchen and through to living room destroying the floor coverings in both rooms. I ask to be advise about what action I should be taking to fix this issue (if it is an issue). Would shutting down the heater till the release action ceases be problematic causing more damage?

Best Regards
Dan1957