Originally Posted by sweets
I notice that about every 3-4 years I need to replace the thermocouple on my boiler because the pilot light keeps going out. At the same time, I remove the 3 burners, tap and clean out all the rust and debris, and put them back as well.
I'm wondering if it's a good idea every year to turn the pilot light on the boiler from the ON position to the OFF position after the heating season, say around April or May, turn the thermostat from Heat to Off, clean the burners at this time and then again in the Fall, around October or when I think I may require heat, to relight the pilot on the boiler. Would I increase the life of the thermocouple and is this a good idea? Any other recommendations?
Running the pilot all summer will help keep things dry and you will have less rust. Some aerated pilots burn so hot that they burn up thermocouples faster.
Slant/Fin boilers had a pilot assembly that burned them up in one year.
When i tested a thermocouple in there pilot it would test 38 to 40 millivolts, so i would reduce the gas pressure on the pilot to get the test down to 28 to 32. thermocouples last longer.
In the fall check your water pressure, turn off water feed valve for a couple of days and leave boiler cold. This will let you know if you have leaks in the system that you can't see. The reason for this test is, if you have leaks and your feed valve keeps putting new water in the boiler you will get a lime build up in the bottom of the boiler and then it will be firing on dry cast iron. This will crack your boiler, and it will need to be replaced.
This can happen in less than two years. I have seen boilers cracked out and replaced in three from new. Later Paul