Troubleshooting the E-10 High Limit Trip Error Code

Overview

The E-10 high limit tripped error indicates that the temperature at the high limit exceeded its trip point of 575°F (300°C). This can occur due to various reasons, including low oil levels, lack of filtration, crumb buildup around the high limit thermocouple and heating elements, excessive carbon buildup from infrequent deep cleaning, loose temperature probes, or issues with the contactor not turning off from the control board.

There are two high limit modules and thermocouples in this system. The upper module, as viewed behind the control, monitors the thermocouple attached to the upper heating element while the lower module monitors the thermocouple attached to the lower heating element.. There is one reset switch shared between both modules. The module monitors the thermocouple, if the temperature of the thermocouple exceeds 575F (300°C), the thermocouple is open or shorted, the module opens a relay to a 24VAC loop going back to the control. The control displays an E-10 high limit tripped error when there is no 24VAC voltage detected back at the control board.

Error Display

The following list provides detail around the letter that appears after the E-10 code:

E-10A: High limit tripped while the main probe was at or above 300°F (148°C).
E-10B: High limit tripped while the main probe was below 300°F (148°C).
E-10C: High limit tripped while cooking. This typically occurs when user skips filtering and skips performing deep cleans.
E-10D: High limit tripped less than five minutes after filtering, and the control returned to cook mode on its own after detecting that the oil was pumped up.
E-10F: High limit tripped while filtering (includes quick filter, daily filter, polish, dispose, drain pan fill from pan).
E-10M: High limit tripped while in melt mode.
E-10S: High limit tripped while in startup mode but not during filter operations.
E-10Y: High limit tripped less than five minutes after the user responded "yes" to the "is pot filled" message. This typically occurs when the oil has not filled back up to the pot and is at least at the bottom fill line.

Call Avoidance

To help the end user resolve the issue without a service call:

Drain the oil: Ensure the vat is empty.
Clean the heating elements: Brush all crumbs down the drain.
Pump up the oil: Fill to the appropriate line (lower fill line for room temperature oil, upper fill line for cooking temperature oil).
Wait 15 minutes: ensure 15 minutes or more has elapsed since the high limit trip to allow time for the oil to cool.
Reset the high limit: Press and hold the high limit reset switch for five seconds. If it doesn't reset, try pressing and holding the white breakers next to the high limit switch for five seconds. If the breakers reset the high limit, service is still required to replace the switch, however the customer can continue to use the fryer.
If the high limit is tripping intermittently, ensure regular filtration and deep cleaning of the vats to prevent crumb and carbon buildup.

Field Troubleshooting

If call avoidance steps do not resolve the issue, proceed with the following field troubleshooting steps.

Recommended Parts:

High limit thermocouple
High limit reset switch
High limit module
Control board

Recommended Tools:

Multimeter
Basic hand tools
1/2 in. wrench
5/16 in. wrench

Troubleshooting a High Limit Reset

If the high limit continually trips or won't reset, do the following:

Initial Checks: Verify all steps from the call avoidance section.
1. Module Lights: Lower the control board for the vat giving the high limit error.
  Check the high limit modules. The upper module monitors the thermocouple for the upper heater. The lower module monitors the thermocouple for the lower heater.
  - Amber light steady, red light off: Module not tripped.
  - Red light on, amber light off: High limit tripped.
  - Red light on, amber light flashing: Fault with the module or thermocouple.
Module Light Flashing: Refer to the blink code chart for a full list of blink codes and replace the faulty part based on the blink code information.
No LEDs: If there are no LEDs on one or more modules and an E-10 error, check incoming power to the module. If line voltage is present, replace the module; otherwise, troubleshoot wiring for open circuit faults.
LEDs in a normal Amber light steady state: If the amber LEDs on both modules are in a steady on state, however the E-10 High Limit Tripped error still displays on the control, unplug connector P13 and perform a continuity check on pins 1 and 2, then perform a continuity check on pins 3 and 4. This checks to ensure the relay is indeed closed at each module. If there is continuity on both sets of pins and this connector, and this connector is securely connected to the control and the high limit tripped error persists, replace the control.
High Limit Reset Switch: Press the high limit reset switch while observing the high limit modules. If the LEDs do not turn off, check the continuity of the normally closed switch and replace if faulty.
Thermocouple Testing: Using needle nose pliers, unplug the top two thermocouple wires and take a millivolt reading. Follow the J type thermocouple chart for range. Test the bottom thermocouple similarly. Replace the thermocouple if out of range; otherwise, replace the high limit module.

Troubleshooting an Intermittent High Limit Trip

Intermittent E-10 Errors: Check for loose connections on the high limit module and reverse polarity on J type thermocouple connections (white wire to positive terminal, red wire to negative terminal).

Troubleshooting a High Limit Trip (oil temperatures exceeding 425°F (218°C))

Oil getting too hot E-10 errors: If there is amp draw to the heating element of the high limit tripping when there is no heat demand, test the heat contactor by removing a coil wire on the contactor, if the contactor still remains closed, replace the contactor. In the rare case the contactor opens when the coil voltage wire is removed, but closes when the coil wire is connected, then replace the control board.