1. Check that the thermostats are level and have proper anticipator settings (if applicable). Electronic thermostats do not require leveling and typically do not have anticipatory settings, but they usually have cycle rate menus. Verify the proper setting is selected.
2. Turn off the power supply
3. Turn off oil supply
4. Check for any water leaks, duct leaks, oil leaks, etc., and repair if found.
5. If a hot water system with diaphragm-type expansion tanks - drop water pressure to "0" and check the air charge in the tank
6. Protect the floor from soot damage with floor covering of your choice
7. Gain access for cleaning of the heat exchanger. Many boilers have side access plates, swing-open doors, or other types of access. They may be hidden under the jacket.
8. Brush down all heating surfaces. If the unit has baffles, remove them, clean the flue ways, and then reinstall the baffles.
9. Re-install clean-out access plates, close doors, etc. These access areas must be sealed. Most will have gaskets. If not, seal with proper sealing material or new gaskets.
10. Carefully remove the vent pipe. Caution - May be hot
11. Brush the interior of the vent pipe. Suggestion: Have a vacuum hose at one end of the pipe to prevent free particles from floating around while brushing.
12. Vacuum chimney base and top of boiler sections.
13. Reassemble the vent pipe and, if needed, seal around the smoke pipe at the chimney base with the proper material.
14. If equipment is supplied with a draft regulator, it must be level and plumb when the vent pipe is reinstalled. The draft regulator should be 18" or more from the boiler or furnace.
15. Check the combustion chamber for debris. Vacuum if needed, taking precaution not to damage the combustion chamber (Note: Not all equipment will have combustion chambers, but this area still needs to be cleaned)
16. Change oil filter
17. Inspect/replace fuel pump strainer (always use a new gasket)
18. Blow oil line with Co2 cartridge if needed (Do not blow lines to underground tanks or tiger loops)
19. Remove, inspect, and clean firing assembly, check porcelains for cracks, and make any electrode adjustments. Check all head adjustments are to the manufacturer's specs.
20. Replace nozzle with proper GPH, spray angle, and flame pattern per manufacturer's specifications *
21. Reinstall firing assembly (do not connect high-pressure line at this time)
22. Clean burner fan blades and burner housing if needed.
23. Double check everything is back to its normal operating condition except the high-pressure line
24. Remove thermostat wires from thermostat wire connections at boiler or furnace
25. Place jumpers on thermostat wire connections
26. Open oil supply and bleed all air from oil line, filter, and fuel pump
27. Have a container on the high-pressure nozzle line to collect a little fuel oil. This is done to protect the filter on the nozzle from contamination due to cleaning the fuel system
28. Change air filters if warm air furnace
29. Inspect/replace/adjust blower belt if applicable. Clean blower wheel blades if needed.
30. Turn on the power supply and the time burner safety shutdown. The burner should shut down within the amount of time the primary control specifies on the rating label
31. Turn off power supply
32. Re-connect high pressure line
33. Connect pressure gauge and vacuum gauge **
34. Turn the power supply on and reset the primary control
35. Allow burner to run about 10 minutes
36. Compare pressure and vacuum readings to manufacturer specs. Most manufacturers operate at 140 psi or higher on newer equipment. **
37. During this time, check all control settings for proper adjustment per manufactures spec.'s
38. Oil all motors where applicable. Newer equipment may have permanently sealed bearings
39. Find the sampling hole in the vent pipe. This should be within one pipe diameter of the appliance and a minimum of 2 pipe diameters before the draft regulator.
40. All tests will be taken at this test point except a draft test, which will have to be taken over fire on negative draft units and in the vent pipe or positive draft units. Today, manufacturers will normally supply this port in a fire observation door. If you have older equipment, you may need to drill a hole in the observation port. You will have to seal this hole for over-fire readings when completed.
41. Verify over fire draft reading is within the manufacturer's specs. For negative draft boilers, it is normally -0. 02. When taking this reading, there should not be any air leaking around your sampling tube.
42. Perform a smoke spot test at the vent pipe test hole.
43. Perform a CO2 reading. Adjust to the manufacturer's specs. Usually 10% to 12.5%
44. Perform a stack temp reading. Compare all test results with the manufacturer's specs ***
45. Check all safety controls for proper operation
46. Remove jumpers from thermostat connections
47. Reinstall thermostat wires
48. Check for oil leaks and that everything is reinstalled and sealed properly.
49. Remove floor covering carefully
50. Wipe down boiler jacket, removing dust and dirty handprints.
51. Complete all paperwork and thank the customer on the way out.

*Older equipment will normally run at 100 psi fuel pump pressure. With many manufacturers operating at increased pump pressures of 140 psi or greater, the maximum firing rate on the rating plate may not accurately reflect the actual nozzle size. See increased pump pressure and nozzle sizing charts from nozzle manufacturers
** Normally, a vacuum test is only needed if the lines are overhead or there is an underground fuel tank. Above-ground tanks and basement tanks, where the tank and appliance are on the same level or the tank is higher than the appliance, typically do not require a fuel pump vacuum test.
*** The over-fire draft test will not be needed on pressure-fired equipment. Most residential equipment is natural-draft chimney-vented and operates on a negative over-fire draft. Typically, a negative draft appliance has an over-fire draft of -0.03 to -0.04 inches. Some equipment today is running in a positive draft condition. This would include direct vent equipment, not to be confused with power-vented equipment.

Disclaimer: The information found on this website is for informational purposes only. All preventive maintenance, service, and installations should be reviewed on a per-job basis. Any work performed on your heating system should be performed by qualified and experienced personnel only. Comfort-Calc or its personnel accepts no responsibility for improper information, application, damage to property, or bodily injury resulting from the applied information found on this website.