I have a sealed combustion boiler that heats both my domestic hot water and my infloor heating system. My boiler is operating properly; however, when my Erie SR201 relay calls for heat the boiler doesn't start up right away. First the relay wasn't calling for heat at all (but water temp was below set limit - I reset power, relay lite came on calling for heat and the boiler fired right up. Now if I reset power, the relay lites up to call for heat, but the boiler doesn't fire right away. It has been eventually firing and satisfying the hot water, but sometimes in takes forever to kick in. It seems to be doing it more and more and waiting longer to fire. I replaced the aquastat as I had a spare, but it didn't solve anything. Any help would be appreciated.