In commercial kitchens, deep fryers are often a central feature. These appliances are in high demand, and they spend most of every meal service working consistently. If your deep fryer suddenly isn't frying or something seems off, there are a few things you can do to narrow down the source of the problem. Here's a look at some of the fryer components you should check if you're having trouble with your unit.

Pilot Light

Without a functional pilot light, your fryer is completely out of service. If the pilot isn't lighting, start by checking the fuel source. Make sure the valve is open on the gas line, because the pilot light needs fuel in order to ignite. If the valve is already open, but you still can't light the pilot, that may mean your supply line is clogged.

You can clear the pilot light orifice by brushing it gently with a stiff brush. This will clear out anything that could be clogging that opening. Then inspect the hose that connects the pilot light to the gas line to ensure that it's connected securely at each end. Inspect your drain valve to be sure that it's closed, because the override switch engages when the drain valve is open. That override switch prevents the pilot light from functioning.


There are several components to your fryer's burner element, and if the burner isn't working, there are a few things you can check. Start by turning the burner knob on the fryer to ignite the flame. If you aren't seeing flames from each of the ports on the burner, that's an indication that some of the orifices may be clogged. Turn the burner off and allow it to cool to the touch. Once cool, clean the orifices with a stiff brush.

Once you're sure that the burner orifices are clean, relight the burner. Watch the flames for any sign of flickering. If the flames are flickering, that's a sure sign that the pressure of the gas is inconsistent. You may need to check your gas lines for clogs or other problems in this case.


If the oil in the fryer isn't maintaining a consistent temperature, or you're seeing fried foods come out too brown, that's a sign that your thermostat isn't functioning correctly. Invest in a probe-style kitchen thermometer to test the temperature of the oil while the fryer is working. This will tell you how consistent the oil temperature is. Your fryer's oil temperature should remain steady at the temperature you set on the knob when there's no food in the fryer. If it's not staying where you need it, you may need to replace the thermostat.

Oil Filter

While the fryer is on, listen for the sound of the pump that filters the oil. If the pump is running, you should also see some movement in the oil that shows the oil circulating. If the oil isn't circulating, inspect the filter pan to see that the seals are all secure. If the o-rings sealing the pump have started to deteriorate, that can cause air leaks that weaken the pressure in the lines. The balance of the air pressure in the lines is essential for the oil to circulate properly, so you'll lose your filtration with a damaged o-ring. You can have the o-rings replaced to restore the system pressure.

These are some of the most frequent problems encountered with commercial deep fryers. If you've run through these steps and still can't narrow down the problem, you may want to reach out to a technician who can thoroughly inspect the fryer and help you with more technical troubleshooting. Get more info by contacting a repair professional.