Frymaster E19

What does Frymaster E19 mean?

The M4000/FQ4000 controller tried to latch the heating circuit — either through the latch relay (K4) on the SIB board or the heat contactor on electric models — and did not receive confirmation that it stayed engaged. The fryer shuts off heating and logs E19. On gas models the latch circuit keeps the 24 VAC control loop energized; on electric models the contactor physically closes the high-voltage heating element circuit.

Symptoms

• Display shows E19 and the fryer stops heating immediately.
• Oil temperature begins dropping below setpoint with no recovery.
• No clicking or hum from the contactor or latch relay when heat is commanded.
• Error may reappear seconds after a manual reset if the underlying fault persists.

Common causes

• Latch relay K4 on the SIB board failed or is not receiving 24 VAC to hold itself energized.
• Heat contactor coil failed open or contacts welded — common on electric models after high-cycle use.
• Open high-limit thermostat breaking the 24 VAC latch-hold circuit at J2 pin 9.
• Loose or corroded connector between the SIB board and the controller (J3 pin 5 signal path).
• SIB board failure preventing the latch command from being issued or confirmed.

Diagnostic steps

1. 01

   Check the high-limit thermostat first

   The latch circuit cannot hold if the high-limit is open. With the fryer cool, measure continuity across the high-limit switch. No continuity at ambient temperature means the switch has failed open and must be replaced before the latch circuit can function.

2. 02

   Inspect SIB board connector J3 and J2

   Power down and unplug the SIB harness connectors. Inspect J3 pin 5 (latch command) and J2 pin 9 (24 VAC hold return) for corrosion, bent pins, or oil contamination. Reseat the connectors firmly and retest.

3. 03

   Observe SIB board LED indicators during a heat call

   Restore power and command heat. On the SIB board, LED 3 (latch) should illuminate and stay on. If it flickers or stays off, the latch relay K4 is not holding — the SIB board requires replacement.

4. 04

   Test the heat contactor (electric models)

   With the fryer in standby and power isolated, measure resistance across the contactor coil terminals. An open reading (OL) indicates a failed coil. Also check that the contactor contacts close cleanly when the coil is energized using a 24 VAC test source.

5. 05

   Replace the SIB board or contactor as indicated

   Replace the confirmed faulty component. After replacement, restore power, command a heat cycle, and verify the temperature rises normally without E19 reappearing. Confirm SIB LED 3 holds steady throughout the heat cycle.

When to call a professional

Call a licensed Frymaster service technician if E19 persists after inspecting the high-limit switch and SIB connectors. SIB board replacement, contactor replacement on electric models, and live 24 VAC circuit tracing require proper lockout/tagout procedures and component-level knowledge of the FQ4000 control architecture. Frymaster service: 1-800-551-8633.