Your high-temp commercial dishwasher relies on its in-built heating feature to clean, sanitize, and dry dishes. So, if it’s not heating, it’s not working entirely for you. Here are some reasons why your commercial dishwasher is not heating. Consult a commercial appliances repair expert to get your unit working again quickly.

Reasons For A Commercial Dishwasher Not Heating

Faulty Heating Element

Most high-temp commercial dishwashers have multiple heating elements. They can burn out after lasting for a few years. This makes it impossible for the dishwasher to sanitize and dry dishes. However, this is the most common cause of a commercial dishwasher not heating or drying, so you should first check the heating elements.

Why do heating elements burn out? A common cause is hard water. Hard water has a high quantity of minerals. These minerals keep depositing on the heating element. At the point when the scale buildup is enough, it can cause the heating element to overheat. With this happening every time it heats up, it burns out very soon.

Furthermore, a defective thermostat can also mess up and trigger the heating element to burn out. It can happen if the thermostat fails to read temperature properly and doesn’t signal the heating element to turn off, then the heating element will keep working until it burns out or the safety switch (high-limit thermostat) shuts it.

Apart from these causes, electrical issues, debris, and heavy usage can also fry the heating elements. Note that a burned-out heating element should be replaced by an expert.

To avoid heating element malfunctions, maintain and descale the dishwasher regularly and install a water softener system.

Thermostat Issues

A faulty or miscalibrated thermostat can keep the commercial dishwasher from heating. A bad thermostat won’t detect the correct water temperature. There can be a case where the thermostat incorrectly detects that the water is still hot when it’s not. So, the heating element will turn off before warming the water. The water may be cold or not hot enough.

The second case is that the thermostat incorrectly detects that the water is cold when it’s hot. The heating element will stay on until it overheats and burns out or the high-limit thermostat turns it off. To avoid and detect problems, use a thermometer to compare the thermostat’s results with.

Tripped Or Faulty High-Limit Thermostat

A high-limit thermostat is a safety thermostat that only takes action when the water temperature is more than the threshold. It trips and shuts down the heating element to avoid overheating. So, if your commercial dishwasher is not heating, the high-limit thermostat may be tripped or faulty.

Tripped High-Limit Thermostat

Tripping means that the high-limit thermostat is fine and it just did its job to turn off power to the heating element due to overheating. So, the heating element won’t function before you reset the high-limit thermostat. You may see a reset button or an error code. Press the reset button so the dishwasher can heat again. However, some newer models have an automatic reset.

Keep in mind that when a high-limit thermostat trips, the dishwasher may run but won’t heat. So, it won’t sanitize and dry dishes. You should resolve the issue that tripped the high-limit before resetting it. You can hire an expert to troubleshoot the commercial dishwasher to fix issues.

Faulty High-Limit Thermostat

A bad high-limit thermostat either won’t power the heating element or won’t cut power if the water overheats. In one case, the dishwasher will run but won’t heat, and in the second case, the dishwasher may be at risk of damage due to overheating.

A sign that the high-limit thermostat is faulty is that you won’t see the reset button pop out on the dishwasher or the reset button won’t do anything.

The symptoms of a tripped and a faulty high-limit thermostat are similar, so try to reset it after fixing the cause and if the dishwasher doesn’t heat, consult an expert.

Bad Heating Element Relay

A heater relay is a small switch that allows the heating element to turn on when it gets the signal from the dishwasher’s thermostat or control board. It opens to allow power to the heating element and closes to turn off the heating element.

If it’s faulty, the dishwasher may not heat or may overheat the water until the high-limit thermostat cuts power. You may hear a clicking sound from the relay (from the dishwasher) with other issues like the dishwasher not heating or overheating the water and error codes. Contact a dishwasher technician to test the relay and replace it if faulty.

Some dishwashers may have a contactor for this purpose, which is more heavy-duty than a heater relay, but performs similar functions for components that need more power, like heating elements and the motor.

Low Water Level Or Pressure

This is a common cause of a dishwasher not heating water because there is not enough water to heat or the water pressure is so low that the heating cycle is not activating. Low water level is also common in other appliances like an ice machine, so check the water levels before consulting a commercial ice maker repair Arlington expert.

Common causes of low water pressure or levels in a dishwasher can be:

Clogged Water Filter Or Water Softener

If the filters get clogged, they will restrict the water flow, so the dishwasher may not fill enough to heat water properly. So, check and clean the water filter or water softener.

Partially Closed Water Supply Valve

Check the water supply valve if it’s completely open. When not open fully, it won’t allow enough water pressure to fill the dishwasher.

Clogged Water Pipes

The water pipes may be clogged due to corrosion or limescale buildup. This can also restrict the water flow and pressure.

Leakage In Pipes Or Hoses

Pipe or hose leakages can also reduce water pressure, so check the entire plumbing system if you suspect there is any leakage. Also, look for kinked hoses.

Faulty Water Inlet Valve

This is a common cause of water level problems. An inlet valve opens and closes to allow water into the dishwasher when signaled by the control board. A faulty inlet valve may stay open, stay closed, or stay partially opened. Two of these cases can cause low water pressure in the dishwasher.

This can lead to the dishwasher not starting the wash cycle at all or the dishwasher washing dishes without heat. Hire an expert who can check the valve for blockages. If not blocked, it may be faulty.

Bad Pressure Switch

A pressure switch controls the water flow into the dishwasher. If the dishwasher is not filling with enough water or overfilling, the pressure switch may be clogged or faulty. Sometimes, the tube connected to the pressure switch gets clogged and causes low water levels. So, clean the tube and the pressure switch if you can or hire an expert so they can also check the pressure switch for problems.

Conclusion

Some issues can trigger the commercial dishwasher to stop heating. So, check for these problems. And hire a commercial dishwasher repair Fairfax Station service, as many of these problems are difficult to identify without the assistance of an expert.