Boiler Tips

Clean out filters on a warm air furnace once every 6 months.
Make sure the return and supply ducts aren't covered by furniture if you have a warm air furnace.
If some rooms become too hot on a warm air furnace, go downstairs and adjust the dampers that are usually on the duct work.
If the ducts go in front of windows in the basement or through other cold area, make sure you insulate them.
Steam heat will continue to heat rooms after the boiler has shut off due to the large radiators, so if you want it to be 70 in the rooms set it to 68.
If some rooms are too hot with steam heat you can adjust a lot of newer steam vents to release the air slower from the radiators. Lower numbers usually mean releasing less air, which means the radiators heats up slower.
Flush the low water cut off often on steam boilers to clean the water.
Make sure you check the water level of your steam boiler often, once or twice a week. Leaking steam vents can cause your boiler to need water more often.
Wrap steam pipes that aren't insulated.
If you have a forced hot water system either turn down thermostats in rooms you don't use and/or buy programmable thermostats to adjust the heat at night and during the day.
Wrap the supply and return pipes on forced hot water and wrap the hot water pipes if you get your hot water from a coil.
Turn down the aqua stat in the summer time if you have a forced hot water system. 200 HI 180 LOW is good for heating season and 180-160 HI, 160-140 for the LOW in summer. Always make sure the LOW and HI are 20 degrees apart.
Clean your boiler once a year, this can save about 5% a year on oil.
If your boiler is more than 30 years old, replacing it might save you upwards of 20% in oil a year.