Commercial refrigeration and HVAC problems, and how long you have
Nine faults, each written out: what you would actually see, what usually causes it, and the point where waiting costs more than the repair.
Most commercial refrigeration and HVAC breakdowns announce themselves days before they stop the line — a cooler that drifts during service, a compressor that never cycles off, or a rooftop unit that short-cycles under load. Each guide below covers the likely causes of one fault, what you can check yourself, and the point at which it needs a technician rather than another week of watching it.
Find the one that matches yours
Each guide covers one fault: the symptoms you would actually notice, what usually causes it, what you can check before calling anyone, and the point at which waiting costs you more than the repair.
- Why Is My Kitchen Exhaust Hood Not Pulling Smoke?
A hood that has stopped pulling is usually mechanical: a slipped or broken fan belt, a seized fan motor, grease loaded into the filters and duct, or a damper stuck shut. A hood also cannot exhaust air the kitchen is not replacing, so a make-up air unit that is off will stop it clearing — which is why the doors get heavy and the kitchen gets hot.
- Why Is My Rooftop Unit Running But Not Cooling?
A rooftop unit that runs without cooling usually has a failed run capacitor, a tripped breaker or high-pressure switch, a refrigerant leak, or an economizer stuck open on outside air. Start at the disconnect and the capacitor, which are the cheapest and by far the most common. A unit short-cycling on a 95°F afternoon is often fighting a condenser nobody has washed.
- Why Is My Reach-In Cooler Not Cooling?
A reach-in that stops cooling is most often an airflow problem: a condenser packed with kitchen grease, a failed evaporator fan, or a door that no longer seals or self-closes. A drifting thermostat or a refrigerant leak accounts for most of the rest. Reach-ins sit in the hottest part of the line, so a condenser that lasts a year elsewhere can choke in months.
- Why Is My Walk-In Freezer Warming Up?
A freezer that is warming up gives far less margin than a cooler. Heavy frost on the evaporator, a refrigerant leak, a failing compressor, or a door gasket pulling in humid air all show up the same way: a box that climbs above 0°F and will not come back down. Product that thaws and refreezes has already lost quality even once it reads cold again.
- Why Has My Ice Machine Stopped Making Ice?
An ice machine that has stopped producing usually fails on water or heat rather than refrigerant: a clogged inlet filter, scale on the evaporator plate, a failed water pump, or a condenser too dirty to reject heat. A bin switch that wrongly reads full will also stop a healthy machine. Filters are a six-month item; a kitchen condenser needs monthly attention.
- Why Is My Walk-In Cooler Freezing My Product?
A cooler that freezes product has lost temperature control, not cooling capacity — the compressor is running past its cutout rather than failing to reach it. The usual faults are a drifting thermostat or sensor, an expansion valve stuck open, or a dead evaporator fan letting cold air pool at floor level. A working cooler sits between 35°F and 38°F.
- Why Is My Walk-In Cooler Not Holding Temperature?
Most walk-in coolers that run without cooling come down to airflow rather than a dead compressor: an evaporator coil iced over, a condenser fan that stopped turning, or a door gasket letting warm air in will each starve the box of heat transfer. A refrigerant leak is the other common cause. Once the box passes 41°F, the product is on the clock.
Not sure which one it is?
That is normal — most faults look like two or three of these at once. Tell us what the equipment is doing and how long it has been like that, and it gets narrowed down on site.