How to Diagnose a Deep Fryer Thermostat

Before determining the work you need to perform on a commercial fryer, you’ll want to inspect some of the key parts it has. This will help you to find the cause for it not working right so you’ll know exactly what you need to fix or replace. If you’re new to the world of commercial kitchens or you’re a veteran tech in need of a refresher, we’ve got you covered on how to diagnose a deep fryer thermostat with this helpful video guide. 

Diagnosing a Commercial Fryer Thermostat

To begin diagnosing, you’ll want to ensure the thermostat is powered on.

• Step 1. Unmount the thermostat – Remove the thermostat knob to begin unmounting. There are screws connecting the bracket to the unit and the thermostat to the bracket that all need to be removed with a screwdriver. 
• Step 2. Disconnect the wires – Disconnect the wires to the thermostat to avoid a false reading. 
• Step 3. Check for continuity while off – Place the knob back onto the thermostat and ensure it’s turned off. Use a multimeter to confirm there isn’t currently continuity.
  • Note. If there is continuity while the thermostat is in the OFF position, you could be dealing with a runaway thermostat.
• Step 4. Check for continuity while on – Switch the thermostat knob to an ON position and use the multimeter to check for continuity. 
• Step 5. Check for continuity once the fryer has reached temperature – Turn the fryer thermostat to a certain temperature. Then, let it cycle a few times to allow the oil to stabilize. Once there is no longer a flame in  the burners, check to confirm continuity isn’t present. 
• Step 6. Check for continuity after raising temperature – Raise the thermostat temperature so the unit is calling for heat and check that it has continuity. 

If the thermostat has continuity when it shouldn’t, or doesn’t have continuity when it should, it is probably time to replace it.