My old Peerless cast iron boiler wouldn’t start up, and a closer inspection revealed a bad thermocouple. Test the thermocouple with a multimeter. Since it’s a relatively simple repair, I decided to take it on my self. A repair of this nature can cost upwards of $300 if you have to call a plumber, even more, if it’s a night, weekend or holiday. The only tools needed are a couple of wrenches and a good light. This is also a good time to blow out the rest of the system and drain some rusty water. Since these thermocouple units are so inexpensive, you should consider having one ready if your boiler or water heater is over ten years old.
NOTE: This is a repair on a gas boiler system and hot water, gas, and electricity are involved. Always follow proper safety procedures. Call a professional if this is too much work, safety first.
