How do you clean your boiler

Cleaning the boiler depends on the type. Steam boilers and hot water boilers are a little different.
Also is your boiler a tube boiler or one with a formed heat exchanger? Fuel oil or natural gas? Size(btu), household or industrial? If you give a little better detail I will give you a better guide.

Fuel oil boilers (household)with the cast iron heat exchangers have a tendancy to build up with ash and soot reducing efficiency. They are generally designed to be opened up and cleaned with a brush. Electricity, fuel needs to be locked out before working on it.

The following is for a commercial type boiler. Lock out electricity fuel and energy sources. If you dont know this you probably shouldnt be messing with it. Water, fire tube boilers are opened on both ends and cleaned with wire brushes. The fire box also should be checked for good refractory and no foreign materials. If the boiler is equiped with water side inspection plates scale and rust should be removed from the bottom of boiler.(commercial boilers) Safetys should be inspected. State regulations and inspections of commercial boilers should be followed.

The reset on the boiler can be going out because of the flame failure sensor(dirty eye), igniter problems(weak, dirty or out of adjustment), low water shutoff, gas pressure sensor(normally resets at valve), air flow sensor(check for obstructions on blower air intake screen) Room can be too airtight and downdrafts will affect the airflow. Also dont put draft induced (blower) water heaters and non draft induced boilers in same area/room. Carbon monixide !

The flame should be blue with a very slight yellow tip as it swirls.