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Serving The Greater
Coeur D’Alene & Spokane Area

Serving The Greater Coeur D’Alene & Spokane Area


ACI Northwest Blog

Common Repair Issues With Rooftop HVAC Units


Commercial buildings widely rely on rooftop HVAC units. This is because they are truly ideal for a long list of reasons: they’re effective, they’re quiet, they have excellent air circulation, they’re out of the way, and more.

But no system is flawless. Every complex system requires maintenance and there’s always a chance that something will go wrong. What can go wrong with rooftop HVAC units? Here are some of the repair needs that are most likely to come up.

Dirty Coils

In a residential air conditioner, the condenser coils are in the outdoor unit, and are thus vulnerable to getting messy from mud splatters or sprayed-on lawn clippings. In a commercial HVAC unit, both the condenser coils and the evaporator coils are in the rooftop unit. There’s not likely to be a lot of lawn mowing going on up there on the roof, but there is considerable opportunity for dirt and mess.

The evaporator coils soak up heat from the building, and the condenser coils disperse that heat. When either is caked with dirt, it’s as though the coils are insulated, slowing down the absorption or the dispersal of that heat. This makes the whole system work harder and can result in breakdowns of the motors or even compressors.

Refrigerant Leaks

The refrigerant flows through the coils, and these are often made of copper tubing. As the system ages, this tubing can deteriorate, leading to cracking that lets the refrigerant leak out. In a system that has become degraded from advanced age, it may be a better investment to replace the system than try to fix it. But sometimes refrigerant leaks occur in newer systems, often because of accidental damage to the coils. In this case, the leaky spots can be sealed, and the system can be refilled with refrigerant. 

Overblown Blower

If the blower just won’t stop, it’s likely an electrical issue. This could be a stuck relay, a failing limit switch, or because the thermostat is miscalibrated, has wiring issues, or is just plain dying and in need of replacement. A qualified commercial HVAC technician can diagnose the exact cause.

Other Electrical Problems

Sometimes the first sign of an issue is that circuit breakers are getting tripped. This may indicate that something is shorting out in the electrical system, or that capacitors (which supply the extra boost of power the system needs for starting up) need to be replaced. Either way, you need professional help with your rooftop HVAC units in Coeur d’Alene, ID

Preventing Repair Needs

The best way to make sure your commercial building’s HVAC system encounters as few problems as possible is to have regular maintenance done. This will keep the coils clean, reduce friction and wear and tear, improve efficiency, maximize cooling power, and catch problems while they’re still very small, before they have a chance to cause expensive damage or inconvenient HVAC failures.

ACI Northwest is here to help. Contact us today to discuss your commercial building’s HVAC system.

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