As I start hearing Christmas tunes being played again this year, and it seems to be earlier every year, thoughts start to turn toward the holiday season and the arrival of colder weather. Whether between choruses of “Winter Wonderland”, “Frosty the Snowman”, or “Baby, It’s Cold Outside” (which annoys me every time it comes on), it seems there are constant reminders about winter once the holiday music starts. With the arrival of winter and higher heating bills, one common question we receive around this time of year centers around how to best operate equipment during the heating season. If you have been paying attention to the market or followed our other blog posts, you also know that natural gas prices are skyrocketing, so it is important to operate equipment as efficiently as possible, especially this year.

I have taken a couple of different approaches in past blog posts about preparing for the winter season, so I also encourage you to read those from previous years. For this post, however, I decided to take a different perspective and focus more on larger central plant equipment.

While not an all-inclusive list, the following are some ways to get your HVAC equipment ready for the heating season and hopefully save energy dollars and potential headaches at the same time.

Boiler Plant Maintenance

  • Perform a tune-up, which should ensure that all system components are functioning properly and there are no blockages in combustion air intake or flue stack.
  • Inspect gas valves and conduct the safety tests recommended by manufacturer.
  • Check that boiler safety valves are operating properly to prevent over pressurization.
  • Check the burner and flames for signs of wear and general burner condition; visually inspect boiler for any significant issues. Check that the boiler is not producing carbon monoxide (CO) due to incomplete combustion or other issues, and make sure CO detectors are operational and functioning properly.
  • Check wiring and electrical connections on control panel.
  • Check the water level and low water cutoff and check for leaks.
  • Make sure flue gases are properly discharged outside.
  • Keep up to date on all manufacturer recommended boiler maintenance service!

Boiler Plant Energy Considerations

  • Analyze combustion efficiency and adjust as needed for appropriate oxygen (O2), carbon monoxide (CO) and nitrous oxide (NOx) emissions.
  • Heat transfer efficiency has a large effect on boiler performance, so tubes should be regularly cleaned; on the water side, check for heavy scaling of the tubes; look for evidence of corrosion.
  • Check insulation on hot water and steam piping, valves, and fittings; repair/replace as needed.
  • Check for steam leaks; leaking steam can cost thousands of dollars a year.
  • Inspect steam traps for proper operation; a steam trap maintenance program can identify malfunctioning traps and keep steam from being wasted.
  • Make sure steam condensate return systems function properly and optimize recovery opportunities.

Cooling Towers

  • Check heat tracing and basin heaters for proper operation to prevent potential for freezing.
  • Make sure nozzles are clean to provide even distribution over fill and maintain minimum flow rate; this helps to prevent icing.
  • Do not operate if no heat load; if heat load drops too low (i.e., water temperature below manufacturer’s minimum requirement), bypass condenser water flow to cold basin.
  • If cooling towers are not needed, winterize towers by draining the towers and exposed piping and properly shutting down; shut off and drain make-up water.

Saving Energy and Reducing Costs

  • Ensure appropriate reset schedules are in place for hot water temperatures and chilled water/condenser water temperatures, if required.
  • A retro-commissioning process for the heating controls and sequences of operation can help identify opportunities for savings and reduce the potential for simultaneous heating and cooling.
  • Check for proper insulation and R-value (the higher the R-value, the better the insulation) and add as needed. Provide weather stripping and caulking for gaps around openings to seal leaks and reduce infiltration of cold air during the winter.
  • Review building automation system settings to make sure no overrides are present in switching from cooling to heating mode.
  • Proper space temperature set points and setbacks (lower heating temperatures when spaces are unoccupied) can help save energy.

Taking a proactive approach to maintaining your heating systems can not only save energy but can also keep your occupants safe and warm this winter season. As the song says, “Oh, the weather outside is frightful, but the fire is so delightful…”