As temperatures dip in Nashua, your commercial HVAC unit faces its toughest test of the year. You need more than a quick filter swap to keep employees and customers comfortable through snowfall and freezing nights. At Joyce Cooling & Heating Inc., in Nashua, NH, we understand how winter strains rooftop units and duct systems alike.
Inspect and Clear Outdoor Units
Cold weather makes it especially important to keep your rooftop or ground-level units clear and free of debris. Walk the perimeter and remove leaves, branches, snow, or holiday decorations that could block airflow.
Make sure the unit is sitting level. Shifting concrete pads or frost heaves can tilt equipment and cause unnecessary wear. If you notice ice forming on the fan blades or coils, call a technician to check the defrost cycle before the buildup damages sensitive parts. A quick visual inspection can also reveal bent louvers or fan guards that allow snow to drift inside. By keeping the area clear and confirming smooth fan operation, you’ll help your HVAC system breathe easily and avoid overwork during Nashua’s coldest stretches.
Verify Thermostat and Control Settings
Your digital control panel is the brain of your heating system, so it’s worth a careful check before winter settles in. Start by confirming that the time and date are correct. Power outages earlier in the year might have thrown settings off. Then review your heating schedules: lower temperatures overnight if the building is empty, and program them to rise about 30 minutes before staff arrive.
Watch for unassigned “away” modes that could accidentally shut off heat in areas that always need it, like server rooms or storage spaces. If you upgraded insulation or installed new door seals over the summer, a technician can recalibrate sensors so your controls reflect the tighter building envelope. For buildings with management software, scan the trend logs for short-cycling or other irregular patterns that point to thermostat or control issues. Properly tuned controls help you keep spaces comfortable while preventing energy waste from unnecessary system restarts.
Examine Air Filters and Dampers
Clean filters keep air moving smoothly and protect your blower motor from unnecessary strain. Replace any filters that look more than half clogged with dust or pollen, even if they haven’t yet reached the manufacturer’s suggested change date. For large commercial spaces, high-efficiency filters with a MERV rating of 8 or higher are a good choice.
While checking filters, also test the motorized dampers that direct airflow to different zones such as lobbies, offices, and conference rooms. Stuck dampers can cut off airflow, leaving cold pockets. One of our technicians can fine-tune these components by realigning linkages, lubricating shafts, and verifying that each damper resets correctly when power is shut off. Together, proper filtration and damper performance ensure even heating throughout your building.
Test Safety and Limit Switches
Safety controls, such as pressure sensors, flame rollout switches, and high-limit controls, are designed to shut your system down if conditions become unsafe. One of our technicians can verify these safeguards by simulating potential issues. For example, they may restrict airflow to confirm that the high-limit switch properly shuts off the burner before the heat exchanger overheats.
Rollout sensors near the combustion chamber should also be tested to ensure they stop the flame if hot gases escape. In systems with a secondary overtemperature sensor, our technician will confirm that it cuts power before ductwork becomes dangerously hot. Skipping these checks could leave your building vulnerable to mid-season breakdowns or, in worst cases, fire hazards. Regular safety testing ensures your equipment reacts instantly to problems, protecting both your staff and property.
Check Heat Exchanger Integrity
A cracked heat exchanger can release carbon monoxide into your ductwork. This is a serious safety risk that’s invisible without testing.
During a professional inspection, our technician will use combustion analyzers and cameras to spot hidden fractures, corrosion, or weak weld seams. They also check flue-gas temperatures and draft readings to confirm that exhaust is venting properly.
If problems arise, some systems allow for the exchanger to be replaced instead of the entire furnace or boiler, which can reduce downtime and costs. Catching cracks early prevents emergency shutdowns in the middle of winter and protects your building from dangerous backdrafts or inefficient combustion.
Assess Condensate Drains and Pumps
Condensing units and boilers send acidic water through drain lines that can clog over time. During a maintenance visit, our technician will check the condensate piping from the drain pan to its discharge point outside, looking for leaks or clogs near elbows. If the line dips or has loose fittings, they tighten up the line.
For systems with condensate pumps, they will test it by pouring water into the drain pan until the float switch activates the pump. They will confirm that it moves water all the way out of the drain line. Additionally, they can replace cracked PVC fittings, add heat-tape cables around critical runs, or swap in a more powerful pump if your setup struggles to discharge condensate properly.
Test Emergency Power and Backup Systems
Winter storms can knock out your main power, leaving your heating system offline when your building needs it most. If your facility has a backup generator, schedule a full-load test before the first cold snap to ensure uninterrupted operation.
Start by using the generator’s built-in test mode or the automatic transfer switch (ATS) test function, which simulates an outage safely. Pay attention to how quickly burners ignite and fans start. Any hesitation may indicate a voltage dip or insufficient generator output. If your generator uses propane or diesel, check that fuel lines are free of condensation and that filters are clean.
Business owners with dual-fuel boilers should conduct a changeover test to confirm that the system switches to auxiliary fuel automatically, without requiring manual intervention. Document any irregularities, and schedule maintenance promptly to ensure optimal performance.
Evaluate Fuel Delivery and Storage
If your building uses natural gas, ensure the meter and regulator remain accessible by clearing away any items that could block access. For propane systems, check the tank gauge and schedule a refill if levels fall below one-quarter full. You want to be prepared for any early cold snaps. Inspect flexible fuel connectors for cracks, corrosion, or leaks near the inlet; worn lines can leak and require an expensive emergency repair.
If you keep on-site diesel or oil, confirm that filters on your day tank are clear of water or sediment and that any water-separator filters are replaced if necessary. Proper monitoring and maintenance of all fuel lines and storage tanks ensure your burners fire reliably and helps avoid emergencies during sudden temperature drops.
Contact Your Local Experts
A thorough pre-winter HVAC inspection ensures your heating coils stay clear, condensate drains remain flowing, and thermostat settings are optimized to reduce your heating bills. We also perform rooftop unit checks, duct sealing, and emergency repairs. Partnering with Joyce Cooling & Heating Inc. means having commercial HVAC experts who understand Nashua’s winter challenges and can keep your building warm and efficient.
Schedule your winter HVAC service today to avoid surprises when temperatures drop.
