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Boiler Annual Maintenance

Optimize your Boiler Performance for Winter


As temperatures continue to drop, it’s essential to ensure your boiler is ready for winter. 

Proper winter startup will give you time to make necessary repairs, ensure your secondary fuel is ready (if applicable) and avoid emergency service calls.  When inspecting and preparing your boiler from summer layup, always ensure you are following the boiler’s manufacturer recommendations.  

Boiler with Fuel Oil

Are you activating an alternate fuel?

If you are switching from natural gas to tap into your fuel oil, make sure your alternate fuel source is operating reliably. If your alternate fuel has been sitting for some time, the quality of your fuel oil may not be ideal for proper boiler operation. Call your energy supplier to request that your fuel source be tested for proper quality. 

Corrosion can occur 

For seasonal boilers, even the best boiler water treatment program must be supplemented to prevent corrosion during the boiler’s non-operating months. Increased oxygen levels can cause pitting in steel tube sheets and boiler tubes.  Boiler Supply can replace or repair any pitted tubes to ensure the reliability and integrity of the boiler.  

Maintenance Check

  1. Inspect the fuel source. No matter if the boiler is burning natural gas, propane or oil, the supply and pressures must be verified, and the piping/valves must be checked for any leakage.  If the boiler is burning heavy oil, the temperature of the oil needs to be verified to ensure proper viscosity for atomization.
  2. Inspect the fireside. A dirty fireside leads to decreased efficiency. Open the fi reside and check the boiler tubes and furnace area for any deposits of soot and non-combustible material and clean as necessary. Also, check the fi reside gaskets for wear and brittlement, replacing these seals as needed.
  3. Check the refractory. All boilers will incur some cracking due to normal expansion and contraction. Inspect the boiler refractory for signs of excessive cracking (more than 1/8”) or erosion. Carefully prepare and build up these areas per the instructions from the manufacturer and/or refractory supplier.
  4. Inspect the waterside. All water-level controls and related inspection points should be opened and cleaned. Remove all manway and handhole plates from the boiler and remove the inspection plugs from the water column tees and crosses. Also, remove the float assemblies from the water column(s), and thoroughly wash all the waterside surfaces. Rod out the equalization lines and/or other related piping to ensure complete openness and replace worn-out gaskets as necessary.
  5. Inspect the burner. While the boiler is open, inspect the burner components. All moving parts should be free and non-binding. Inspect the shutter, burner baffle, damper, oil nozzle(s) and diffuser to ensure that all parts are in proper working order, are properly aligned per the manufacturer’s instructions and are not overheated, distorted or cracked.
  6. Inspect the controls. Any controls used to monitor the water level of the boiler should be checked for proper mounting position, wiring, switch integrity, alignment and mechanical operation after reinstalling on the boiler. Before starting the boiler, inspect all of the operating controls for both mechanical and electrical integrity, paying special attention to visual signs of overheated wiring or switches. These operating controls can be found on the boiler’s electrical wiring diagram and will be electrically tied into the boiler’s burner management system, also known as a programmer or flame safeguard. If the wiring within the control is found to be defective or compromised, replace the control in its entirety. Do not attempt to rewire the internal control or replace its switches.
  7. Close all openings. Make sure that all of the boiler’s doors, manways and handholes are properly closed and gasketed, the boiler’s blowdown valves are closed, and the safety valve(s) are properly installed and vented.
  8. Open the boiler’s valves. This includes the boiler’s headerBoiler Maintenance valves, piping drains and vent valve.
  9. Test the pumps and valves. Test operate the pumps and valves to ensure proper operation.
  10. Warm up your boiler. When the boiler is started from a cold state, be sure to bring the pressure up slowly to allow joints and metals to heat up evenly and reduce expansion stress.
  11. Switch to automatic operation. Do this once the boiler has reached the desired operating pressure.
  12. Analyze combustion. Perform a full combustion analysis. This step will help to optimize performance, verify component operation, lessen maintenance requirements, and minimize fuel requirements, thereby lowering operational expense.
  13. Water treatment. Test and treat the boiler water as instructed by the manufacturer. Also, it is a good idea to consult with a water treatment expert for a specific treatment program for your situation. Newly filled boilers and freshly started deareators may require additional testing until the water chemistry reaches a “normal” balance. This will typically take a few days.
  14. Monitor your boiler. Closely monitor the boiler for the first few days after start-up to check for leaks and any additional maintenance items that may occur as the boiler and systems expand and reach operational temperatures.

Boiler Supply can take the headache out of tuning your boiler.  Our experienced technicians can properly clean, tune and dial in your boiler’s combustion.  

We are an authorized Cleaver-Brooks Representative with factory-trained technicians; however, we can service just about any make or model boiler available.  Contact us to schedule an appointment.