The Only Boiler Maintenance Checklist You Will Ever Need | RasMech

6 min readNov 18, 2020

A study conducted by the National Board of Boiler and Pressure Vessel Inspectors, attempted to find the cause behind most boiler incidents. What they found was that poor maintenance practices and defective low water cutoffs were generally the culprit. Including more serious incidents that result in injuries and building damage. Our boiler maintenance checklist will help ensure you don’t become a statistic in this study.

Routine maintenance is critical to ensure a boiler system remains reliable, safe and efficient. Below are recommendations for daily, weekly, monthly, semi-annual and annual tasks. As always, follow your manufacturer’s recommendations for routine maintenance and maintain a daily boiler log book.

Daily Maintenance

1. Check water level glass gauge, record the pressure gauge and temperature gauges.

2. Check LWCO and ALWCO operation — blowdown water column — make the burner shut down.

3. Drain gauge glass.

4. Turn off burner control switch, observe response to flame failure.

5. Observe operating control and high limit control.

6. Perform Bottom Blowdown to remove sludge and sediment.

7. Observer Burner refractory cone, looking for broken chunks.

Weekly Maintenance

1. Check all linkages on burner controls and on the automatic draft controllers.

2. Check air damper on burner.

3. Check valve operation in gas train.

4. Check pilot and igniter, look at the condition of flame.

5. Check operation of LWCO — blowdown boiler water level through drain. Watch gauge glass to see burner cut off before losing sight of water.

Monthly Maintenance

1. Test limit controls on boiler.

2. Test flame detection controls.

3. Check blowdown for sludging at bottom of boiler.

4. Verify blowdown separator and cooler operation.

5. Check floor drains for proper function.

6. Check boiler fresh air inlet screens.

Annual Maintenance

1. Disassemble and check LWCO and ALWCO for sludge, corrosion or electrical switch defects.

2. Verify and tune up burners and settings. **We recommend quarterly tuning by a qualified technician**

3. Inspect fire side for soot or damage and water side for scale or corrosion & Clean the boiler inside and out.

4. Hydro test boiler for leaks (tube joints and piping).

5. Inspect all refractory for fallen broken chunks.

6. Check gas regulator pressure settings.

7. Replace or re-certify safety valves.

8. Bubble test fuel train safety shut-off valves.

Download Our Printable Boiler Maintenance Checklist Here

Recommended Boiler Maintenance Checklist

After a service provider adjusts the burner, they should not be adjusted by persons not experienced with burner systems. This includes tinkering with linkage settings, fuel pressures and control settings. Service calls caused by “tinkering” or poor maintenance procedures are not typically covered by any guarantee or service plan.

General Maintenance

1. Keep the boiler, burner and entire boiler room clean. A clean boiler room is essential to first class boiler operation.

2. Keep the burner and boiler control covers in place. The electrical contacts in the controls are very sensitive.

3. Never close vents supplying air to the boiler room. If cold air currents cause difficulty with other boiler room equipment, install air ducts to direct the flow of fresh air.

4. Repair all leaks promptly. All piping connections to the boiler and burner should be leak free because even a minor leak, if neglected, may soon become serious.

5. Foaming or priming may occur in a steam boiler and cause large quantities of water to pass over into the steam main. It can be detected by violent fluctuations or sudden dropping of the water level in the glass. This will result in nuisance shutdowns of the burner due to the low water cutoff shutting off the burner. This may be caused by dirt or oil in the boiler water, an overdose of boiler compounds or carrying too high a water level. In case of serious trouble, stop the burner and decrease the load on the boiler. Then correct the condition according to the boiler manufacturer’s instructions.

Daily Maintenance

1. Check boiler water level in the sight glass and the steam pressure on the gauge to the steam boilers. Check temperature reading and water pressure on hot water boilers. Record this in your logbook.

2. Check the low water cutoff operation by opening the blow down valve on the low water cutoff to remove rust and dirt. Determine that the burner cuts out with low water in the sight glass. Immediate corrective action must be taken if burner does not cut off with low water in the sight glass. Record this in your logbook.

3. Turn off burner control switch and close pilot manual gas cock. Turn on burner control switch and determine that burner flame safeguard locks out on flame failure before the main gas valve is energized. Immediate corrective action must be taken if flame safeguard does not lock out to indicate flame failure. Record this in your logbook.

4. Observe the operation of the boiler limit and operating controls to determine that the burner is being cut off at the proper setting. Adjust per the manufacturer’s instruction sheet as required. Record this in your logbook.

Weekly Maintenance

1. Check all burner linkages. Tighten if necessary. Record this in your logbook.

2. Test the low water cutoff by opening the boiler blowdown valve to remove rust and dirt from the boiler mud leg or drum. Determine that the burner cuts off when low water point is reached in the sight glass. Record this in your logbook.

3. Check all phases of the operation of the control circuit for proper operation. Record this in your logbook.

4. Operate burner manual shutoff valves to determine that they are working freely and properly. Lubricate if necessary. Record this in your logbook.

5. Perform all tests and inspections required under “Daily Maintenance.”

Monthly Maintenance

1. Check pilot assembly. Record this in your logbook.

a. The ignition electrode must be centered in the igniter body.

b. The ignition electrode and pilot assembly should be inspected and cleaned if necessary.

c. The high tension wire between the transformer and the ignition electrode should be checked for deterioration.

d. The flame scanner should be inspected and cleaned if necessary.

2. Check air dampers for smooth operation. Remove accumulation of lint or dirt. Record this in your logbook.

3. Oil firing.

a. Check ignition electrodes. Clean if necessary.

b. Clean oil atomizing nozzle if necessary.

c. Inspect oil filters. Replace or clean filter cartridge if necessary.

d. Inspect filter on air compressor, if used. Record this in your logbook.

4. Lubricate motors in accordance with motor manufacturer’s instructions. Record this in your logbook.

5. Perform all tests and inspections required under “Weekly Maintenance”.

Annual Maintenance

1. Have the burner inspected and checked by a qualified service representative. Record this in your logbook.

2. If the boiler is to be out of service for the summer, close all manual valves. Tum off burner by control switch, being sure to leave electrical power on the control panel. Leaving power on the control panel will prevent humidity damage to the flame safeguard.