Winter brings unique challenges that put extra stress on HVAC systems. The increased heating demand can cause various issues that affect crucial components or full systems, leading to cold indoor temperatures and even safety risks. it is important that facilities have stable, efficient HVAC systems through the winter to ensure comfort, health, and productivity for occupants. For some facilities, reliable heating is even more vital. The occupants in senior living facilities, nursing homes, and schools or daycares are most vulnerable to cold-related risks. Hospitals rely on heat for patient care and equipment operation. And industrial or manufacturing facilities may utilize temperature-sensitive processes or equipment. Understanding the risks posed to HVAC systems from cold weather is key to preventing them.

HVAC Problems Caused by Cold Weather 

• Frozen coils & pipes: Freezing temps can cause frozen evaporator coils or pipes in HVAC systems. Specifically, a dangerous buildup of ice will lead to restricted airflow throughout the system and cause various malfunctions. Poor airflow reduces the amount of heat that can be transferred, leading to cold indoor spaces. Refrigerant levels drop in cold weather which can also lead to freezing coils or pipes, which may burst and cause additional water damage to the system or surrounding area. Be on the lookout for low refrigerant and ice buildup.
  
  
• Cracked heat exchangers: Metals contract in cold weather, and older or stressed heat exchangers can crack, leading to system failure and potentially carbon monoxide leaks. If you have an aging furnace, it’s a good idea to install carbon monoxide detectors to ensure occupant safety in the event of a leak. Poor airflow from ice buildup can also cause the heat exchanger to overheat and fail prematurely.
  
  
• Blocked or frozen vents: Snow or ice can block intake or exhaust vents for furnaces. This can lead to poor airflow in the system, ineffective heating, pressure issues that damage other components, or a dangerous buildup of exhaust gases.
  
  
• Thermostat or sensor malfunctions: Extreme cold can lead to inaccurate readings on battery-powered thermostats, poor temperature regulation, system disruption, and short cycling. Short cycling is when a furnace turns on and off repeatedly without completing full heating cycle, leading to inefficient warm temperatures indoors.
  
  
• Condensate lines/drains freezing: In furnaces or heat pumps, low temperatures can cause condensate to freeze in drain lines. This leads to backups or water damage, which can harm other crucial system components. It’s important to ensure furnace rooms are warm and ventilated throughout the winter.
  
  
• Blower motor failure: Low temperatures can cause freezing moisture which impacts the blower motor. It may experience intermittent operation or difficulties or failure to start. Internal components like bearings or brushings can also be affected by freezing temperatures and reduce the blower motor’s performance.
  
  
• Compressor issues: Cold weather can thicken oil in the compressor which leads to pressure drops and component wear. This means the compressor may fail to start or it must work harder than normal. Frozen coils also increase the strain on the compressor, increasing the likelihood of failure. One solution that helps avoid compressor issues is utilizing crankcase heaters. These are heating elements that warm oil and prevent refrigerant from migrating into the crankcase during off cycles. This prevents the dilution of lubricating oil which will thicken in compressors during winter.

How to Prevent HVAC System Damage in Winter

Below is a checklist of some steps you can take to ensure winter weather will not impact your HVAC system.

• Inspect and replace air filters every 30-90 days in winter, more frequently in high-risk facilities.
• Inspect refrigerant levels regularly.
• Seal ductwork.
• Apply insulation to pipes or other vulnerable sections.
• Insulate condensate lines with foam sleeves or pipe wraps.
• Keep vents and outdoor units free from snow or ice. Apply vent covers or hoods to shield from buildup.
• Replace batteries in thermostats.
• Lubricate blower motor bearings and inspect belts.
• Schedule regular HVAC maintenance to identify potential failures or aging equipment.
• Stock backup parts like filters, ignitors, sensors, and thermostats.