In the heart of Philadelphia, where the blend of historical charm and modern living creates a unique environment, homeowners face the task of maintaining a comfortable indoor atmosphere year-round. A common hiccup in achieving this comfort is an issue known as "short cycling" in HVAC systems. This phenomenon not only affects your home's comfort levels but can also have implications for energy efficiency and system longevity. In this blog post, we’ll explore what short cycling is, why it's a concern in Philadelphia homes, and how you can address it effectively.

What is Short Cycling?

Short cycling occurs when your HVAC system turns on and off more frequently than normal, without running long enough to reach the desired temperature setting. This erratic behavior is not just a nuisance; it can signal underlying problems that, if left unattended, could lead to increased energy bills and premature system failure.

Why Does Short Cycling Happen?

Several factors contribute to short cycling, but common culprits include:

  • Oversized HVAC Systems: In their quest for maximum comfort, some homeowners opt for a system with a higher capacity than needed. While this might seem like a good idea, an oversized system heats or cools the space quickly and shuts off before completing a full cycle, leading to short cycling.
  • Dirty Air Filters: Clogged filters restrict airflow, causing the system to overheat and shut down prematurely. Regularly changing your air filters can prevent this issue.
  • Thermostat Issues: Incorrect thermostat placement or malfunctions can cause your HVAC system to receive inaccurate readings, leading to short cycling.
  • Low Refrigerant Levels: For cooling systems, low refrigerant levels can cause the unit to shut off before it has adequately cooled the space.

Addressing Short Cycling in Your Philadelphia Home

  1. Regular Maintenance: Regular check-ups by a professional service, such as McCorry Comfort, can keep your system running smoothly and efficiently. A well-maintained unit is less likely to experience short cycling.
  2. Proper Sizing: If you're installing a new system or replacing an old one, ensure it's correctly sized for your home. A professional HVAC contractor can assess your home’s needs to recommend the appropriate size.
  3. Air Filter Replacement: Make it a routine to check and replace your air filters every 1-3 months, depending on usage and filter type, to maintain proper airflow.
  4. Thermostat Check: Ensure your thermostat is correctly placed away from direct sunlight, drafts, doorways, windows, and any heat sources to avoid false readings.
  5. Address Refrigerant Leaks: If your cooling system is low on refrigerant, it could be due to leaks. Have a professional inspect and repair any leaks and refill the refrigerant to the correct level.


Short cycling is a prevalent issue among Philadelphia homes, but with the right knowledge and approach, it can be resolved, leading to a more comfortable, efficient, and longer-lasting HVAC system. Embracing regular maintenance, proper system sizing, and attention to component health are key steps in preventing and addressing short cycling. Remember, a smoothly running HVAC system is the backbone of home comfort, especially in the ever-changing Philadelphia climate.