You walk into your office building, and it feels freezing, but the thermostat says it’s 72 degrees. Or maybe it's hot and stuffy, yet the screen shows it’s cooling. It’s frustrating—and confusing. If your building doesn’t feel right, even when the numbers say it should, it’s more than just an inconvenience. It could be driving up your energy bill, stressing out your staff, or making your tenants and customers uncomfortable.
At Harold Brothers Mechanical Contractors, we’ve helped hundreds of businesses all across New England figure out why their HVAC systems aren’t doing what they should. From office buildings to schools to industrial sites, we’ve seen just about every heating and cooling issue you can imagine—and we know how to fix them.
By the time you finish reading this article, you’ll know what to check before calling for help, what your internal maintenance team might be able to fix, and which issues require the expertise of a licensed HVAC professional. We’ll walk you through each category in plain language, with real-world examples, so you can take confident steps toward solving the problem and getting your building back to feeling comfortable.
Sometimes, it’s the little things that cause the biggest headaches. Before you assume your HVAC system is broken or call in a technician, it’s worth checking a few simple things. These quick fixes could save you time, money, and a whole lot of frustration.
Run through this easy checklist first:
Many commercial buildings use programmable thermostats. If someone accidentally changed the schedule or settings, the system might not be heating or cooling when you expect it to.
Fix: Double-check the schedule and setpoints. Reset if needed. Some thermostats have a “Hold” setting that can override the schedule—make sure it's not stuck on that.
Power outages or electrical surges can flip breakers or reset systems.
Fix: Check the breaker panel to make sure nothing has tripped. Also, confirm the HVAC unit is switched on at both the thermostat and system control.
Even cracked windows or propped-open doors can throw off your system, especially in extreme temperatures.
Fix: Walk around and make sure all entry points are shut tight.
It’s common for furniture, rugs, or storage boxes to block vents. That stops air from flowing properly.
Fix: Make sure all supply and return vents are open and unblocked.
If the quick fixes don’t solve it, the issue might be something small but a bit more technical. These are common problems that don’t always require a service call, especially if you have a handy maintenance team.
Clogged filters restrict airflow, which makes it harder to heat or cool your space. The thermostat may be working fine, but the system can’t keep up.
Fix: Replace filters every 1-3 months, depending on usage and environment.
If your building has outdoor condenser units, make sure they aren’t blocked by leaves, snow, or debris.
Fix: Clear at least 2 feet of space around the unit.
Sometimes the thermostat itself is the problem. Low batteries or loose wiring can make it send the wrong signals.
Fix: Change the batteries or have maintenance check the wiring connections.
If the thermostat is near a sunny window, drafty door, or heat-producing equipment, it may not give an accurate reading.
Fix: If possible, move it to a more central location, or add remote sensors.
If you’ve ruled out the easy stuff and your team’s already checked the minor issues, it’s time to call in a pro. These problems are more complex and could lead to system failure or wasted money if ignored.
If some areas are hot while others are cold, your zoning system could be out of sync. Dampers may be stuck or sensors may be misreading temperatures.
Solution: A technician can test and recalibrate zoning components or recommend upgrades to balance the building.
Even digital thermostats can lose accuracy over time. Some may need recalibration or replacement, especially if they don’t match actual room temperatures.
Solution: A professional can use calibrated tools to test accuracy and upgrade if needed.
Worn-out blower motors, cracked heat exchangers, or failing compressors can all lead to poor comfort control, even if the system seems to be running.
Solution: Licensed technicians have the tools to diagnose and safely repair or replace these parts.
If your building was renovated, added onto, or the number of people using it has changed, your HVAC system might be too small, or too large.
Solution: Your HVAC service company can perform a full load calculation and recommend right-sized solutions that fit your current space and usage.
Just because your thermostat says 72° doesn’t mean your building actually feels that way. When the numbers don’t match the comfort level, it’s a sign that something needs attention.
From blocked vents and airflow restrictions to zoning issues and faulty sensors, there are many reasons for temperature mismatches. Some fixes are simple—others require a trained professional. Knowing which is which can save time, energy, and frustration.
By handling basic checks yourself, assigning minor fixes to your in-house team, and knowing when to call licensed HVAC experts, you can restore comfort and avoid bigger problems down the line.
If you're still not sure if you can handle the work, here’s a quick guide that breaks down when to use your in-house team and when to bring in a licensed HVAC contractor. Harold Brothers is here to help, whether it’s a quick fix or a long-term solution. Let’s make your building feel just right.