How Summer Heat Affects HVAC and Refrigeration Equipment (and What You Can Do About It)

When Summer Turns Up the Heat, Your Equipment Feels It Too

When temperatures climb into the 90s and beyond, even well-maintained HVAC and refrigeration systems can start to struggle. In the New Hampshire Lakes Region, where heatwaves are becoming more common, it’s not unusual for facility managers and business owners to notice systems running longer, failing to maintain set points, or even breaking down.

Understanding how heat affects equipment—and what you can do about it—can help avoid costly repairs, keep tenants and customers comfortable, and protect valuable assets.

Why HVAC Systems Struggle in Extreme Heat

Commercial HVAC systems are designed to perform within a certain temperature range. But when outside temperatures rise significantly above that design threshold, systems are forced to work harder to remove heat from the indoor environment.

This increased demand can lead to:

Constant cycling or extended run times
Difficulty reaching or maintaining thermostat settings
Tripped breakers or overworked compressors
Higher humidity levels and uncomfortable indoor conditions

If the equipment is older, undersized, or not recently maintained, it’s more likely to falter when it’s needed most.

Refrigeration in Non-Conditioned Spaces: A Hidden Risk

Walk-in coolers, freezers, and other refrigeration units often live in spaces without air conditioning—like kitchens, back rooms, or storage areas. When these spaces heat up in the summer, the equipment can’t reject heat efficiently, making it harder to maintain set temperatures.

This not only stresses the system, but it also puts perishable goods at risk. In some cases, the internal temperature of refrigeration equipment may rise enough to spoil food or compromise product integrity—even if the unit appears to be running.

The Condensation Problem No One Wants

Ever see ductwork dripping or water puddling under HVAC units? That’s condensation—and it’s common in high-humidity summer conditions.

When warm, moist air meets a cold surface like ductwork or evaporator coils, water droplets form. This “sweating” can cause:

Water damage to ceilings and walls
Mold or mildew growth
Slip hazards on floors
Reduced equipment performance if coils are wet or blocked

What You Can Do to Protect Your System

While you can’t change the weather, you can take steps to help your HVAC and refrigeration systems handle it better:

Schedule seasonal maintenance before summer peaks
A technician can clean coils, check refrigerant levels, inspect electrical components, and spot issues before they become emergencies.
Improve airflow in hot areas
Add ventilation fans or exhaust systems to remove heat from non-conditioned spaces housing refrigeration or HVAC equipment.
Insulate and seal
Insulate cold lines, seal leaks around doors and ducts, and prevent warm air infiltration into cool spaces.
Set realistic expectations
On extremely hot days, systems may not be able to maintain “ideal” temperatures. Remind tenants or staff that comfort may fluctuate slightly during heatwaves.

Know When to Call in the Pros

If your system is short-cycling, failing to cool, or you’re noticing rising humidity levels indoors, don’t wait until it breaks. Proactive service can prevent downtime, protect your investment, and keep everyone more comfortable through the hottest weeks of summer.

Heat is tough on HVAC and refrigeration systems—but with proper planning, smart upgrades, and seasonal maintenance, your equipment can keep its cool. If you’re concerned about performance during peak summer, Wicked Cool Mechanical can help assess your system, suggest improvements, and make sure you’re ready for whatever the season brings.

When Summer Turns Up the Heat, Your Equipment Feels It