Walk-in cooler running warm? The 7 most common causes

A walk-in that won’t hold temperature puts your product and your health inspection at risk. Here are the problems we find most often on walk-in calls around Seattle, roughly in order of how often we see them.

1. Dirty condenser coil

The condenser has to dump heat. When it’s caked with grease, dust or, on rooftops near smokers and kitchen exhaust, smoke residue, it can’t, and the box warms up. Coil cleaning is part of every refrigeration maintenance visit for this reason.

2. Iced-up evaporator

If the coil inside the box is a block of ice, air can’t move across it. Usual causes are failed defrost heaters or timers, a bad defrost termination, or the door being left open.

3. Door gaskets and closers

Torn gaskets and doors that don’t close all the way let warm, wet air in all day. That means more ice, longer run times and warmer product. Gaskets are cheap. Lost product isn’t.

4. Failed fan motors

Evaporator and condenser fan motors wear out. A dead fan can look like a refrigerant problem until someone checks it.

5. Low refrigerant charge

A leak means low capacity and eventually a failed compressor. Topping it off without finding the leak just puts off the fix.

6. Controls and sensors

Bad thermostats, controllers and sensors can short-cycle the system or shut it down early.

7. Equipment at the end of its life

Sometimes it’s time. We’ve replaced walk-in evaporators and full condensing unit systems for Seattle restaurants this year, sized for how the kitchen actually uses the box.

What you can check before you call

• Is the door closing and sealing all the way?
• Is the evaporator coil iced over?
• Are the fans inside the box running?
• Is anything blocking airflow around the coil or the condenser?

If you see ice on the coil or the box keeps climbing, call us before you lose product. Commercial refrigeration service.