Keeping your heating, ventilating, and air conditioning (HVAC) equipment on a regular maintenance cycle is one of the least-expensive and easiest ways to reduce operating costs and avoid costly repairs. Your manufacturer's guide should recommend a program specific to the equipment, but certain areas should be checked regularly.

Heating Equipment

Furnace/Boiler Maintenance

You could save as much as 5% on energy costs by regularly checking and maintaining the efficiency of your boiler or furnace.

• Frequently check the flue gas composition to determine combustion efficiency. The correct gas composition should be:
  CO2:  9% - 10% (gas-fired unit)
         11.5% - 12.8% (using #2 oil)
         13.0% - 13.8% (using #6 oil)
         No carbon monoxide
• You should also examine the flue for hydrocarbon, carbon, and flash buildup
• Measure the exhaust gas temperature. An abnormally high stack temperature (more than 150° above steam or water temperature) may indicate too much combustion air or dirty or deteriorated heat exchanger surfaces
• Clean the heat exchanger surfaces often
• Clean water handling equipment to eliminate lime and scale buildup
• Keep furnace or boiler tubes free of soot, sludge, or flash
• Replace automatic blowdown cycle on boilers as needed
• Maintain insulation on boiler
• Frequently calibrate controls
• Check for water leaks
• Check for air leaks in combustion chamber
• Periodically check the fuel oil temperature
• Keep economizer and preheaters clean
• Keep fan lubricated per manufacturer's recommendations
• Check fan blades
• Check fan rotation and alignment

Electric Heaters

• Calibrate controls often
• Check heat transfer surfaces for obstructions and keep clean
• Check fan rotation and alignment
• Keep fan lubricated per manufacturer's recommendations
• Clean fan blades

Infrared Heaters

• Check and adjust beam direction when necessary
• Dust reflectors with a soft cloth

Refrigeration Equipment and Chiller

• Keep heat exchanger surfaces clean
• Check refrigerant level. Add more if air bubbles are present in the sight glass, or if the refrigerant flow is turbulent
• Check for leaks in the suction and discharge lines
• Keep liquid lines and strainer free of clogs
• Replace worn belts and check for correct tension and alignment
• Check fan rotation and alignment
• Keep fan lubricated per manufacturer's recommendations
• Clean fan blades
• Check compressor gauges for stable system pressure and normal discharge temperature
• Check the compressor for leaks
• Maintain air-cooled condensers
  

  -Tighten or replace the fan belt when necessary.
  -Lubricate the motor following the manufacturer's recommendations.
  -Check for leaks in refrigerant piping.
  -Keep the condenser fins straight/clean and free from obstruction.

• Maintain evaporative condensers.

  -Repair leaks in the piping
  -Clean the coil regularly
  -Clean the air inlet screen

• Maintain water-cooled condensers

  -Clean the condenser shell and tubes.

• Maintain the cooling tower.

  -Keep free of lime or scale deposits
  -Clean heat exchanger surfaces
  -Adjust or replace V-belt as required
  -Clean the intake strainer
  -Check the overflow pipe clearance for proper water level
  -Check for an even water depth in the basin in the gravity-distributed tower
  -Clean and adjust the distributed and spray-filled nozzles

• Maintain absorption equipment.

  -Clean the strainer and seal tank

• Lubricate valves
• Maintain the insulation

  -Look for signs of moisture and feel along the outside of ducts for hot or cold spots that may indicate missing insulation
  -Repair any torn or loose insulation

• Maintain electronic air cleaners
• Frequently clean the ionizing grounding place section
• Replace filters as needed
• Keep airways free from obstructions
• Make sure dampers operate properly and move freely
• Clean filters frequently and replace or adjust those that do not fit properly
• Check fan rotation and alignment
• Keep fan lubricated to manufacturer's recommendations
• Clean fan blades
• Periodically calibrate HVAC thermostats and control devices
• Tighten and clean thermostat contacts
• Keep thermostats away from heat- or cold-producing sources that could interfere with readings
• Maintain pneumatic control systems according to manufacturer's recommendations