While longer cooking times are easy to notice, there are other signs that equipment needs service.

Whether you’re talking health, cars or kitchen equipment, catching a problem early is always best. It lets you avoid a lot of expense, trouble and pain.

For professional kitchens — even those that undergo regular planned maintenance — operators should keep an eye out for the early signs of trouble.

The biggest sign of a problem for cooking equipment is one that operators tend to notice quickly: longer cooking times, according to Daniel Reese, director of training for the Commercial Food Equipment Service Association (CFESA). “What used to take 20 minutes takes ten, what used to take three minutes takes five. That’s the first signal something’s wrong.”

Longer cooking times aren’t the only sign, though. Operators should keep their eyes, ears and even nose open for other, less obvious signals that something is wrong.

If an operator hears unusual sounds clicks, chattering or buzzing noises — that’s a good indication something is wrong with any piece of equipment. Sometimes these sounds will connect to an issue that hurts cooking times. Debris in a convection oven’s fan can make noise and prevent the proper movement of air and slow cooking, for instance. In other cases, though, the sounds may not relate to cooking times, but will still indicate something is wrong. A chattering sound, for instance, may come from an electrical connection in the equipment that’s nearing failure.

Operators should also keep an eye on the flames produced by their gas-fired equipment such as a range. If a burner generates a yellow flame, something is wrong. The unit could require recalibration, for instance, or the flow of gas to the burner could be partially blocked.

In the later case, this can result in what’s known as incomplete combustion, in which not all the gas fed to a unit is fully burned. Incomplete combustion smells similar to gas, and can burn the eyes just a bit, says Reese. It also puts out soot. Ovens with incomplete combustion will have discolored spots on the wall or soot buildup on the hood near the flue.

Flattop Repair Signals

While most hot side units take longer to cook when malfunctioning, Reese says that there is an exception: the flattop. By its design, the burners on these units are hard to clog, while the thermostat bulbs are easy to damage. When the bulb gets damaged, the piece then ends up having just two modes, on and off, with no modulation. When a damaged unit is on, then, it tends to run very hot. In addition to faster cooking times, operators can identify this situation by examining the cooking surface, which develops a blue tint when it get overheated regularly.

Signs of cold side problems tend to mirror those of hot, says Reese. A sure sign that a unit needs service is that it isn’t keeping food as cold as it once did. Often, operators end up turning the temperature setting down to make up for poor performance. This is a sure sign that the unit needs service, or at least a thorough cleaning. There are other indications something is wrong, though. A unit could be running louder or longer than normal, meaning it’s having to work harder to do the same job. Water pooling under reach-in units is also a sign of trouble, possibly a clogged drain line or faulty condensation pan.

Operators should also keep an eye out for condensation on the doors of glass door refrigerators, Reese says. These pieces typically have built-in door warmers that heat the glass just enough to stop the buildup of condensation. If condensation does build up, that’s a sign the warmer has failed. If there’s also no warmth on the gasket or door frame, that’s almost certainly the problem.

While some signs of equipment trouble are hard to miss, others are more subtle, but no less serious. By keeping an eye out for these signals, operators can avoid major breakdowns, solving big problems before they start.