Frymaster E37 Error Code
Automatic intermittent filtration (AIF) probe failure. The AIF/VIB probe RTD reading is out of range; filtration disabled. Call service.
Source: Frymaster FQ4000/M4000 Service Manual (819-7955)
What does Frymaster E37 mean?
The Automatic Intermittent Filtration (AIF) system uses a dedicated RTD probe — mounted on or near the VIB board — to monitor oil temperature in the filtration circuit. E37 means this probe is reading outside its valid range, indicating a failed probe element, open wiring, or a short circuit. Because AIF relies on this temperature reading to determine safe filtration conditions, filtration is disabled when the probe reading is invalid.
Symptoms
- Display shows E37 and automatic filtration is disabled.
- Scheduled or on-demand AIF cycles do not initiate.
- Cooking continues normally, but oil quality degrades without filtration.
- Error persists across power cycles if the probe or its wiring has failed.
Common causes
- Failed AIF/VIB RTD probe — open or shorted element.
- Damaged wiring harness between the AIF probe and the VIB board.
- Loose or corroded connector at the probe terminal on the VIB board.
- Oil infiltration into the probe conduit causing wiring damage or short circuit.
Ask the AskWhiz AI about Frymaster E37
AskWhiz
online
Diagnostic steps
Power down and locate the AIF probe
Switch the fryer off and allow the filtration circuit to cool. The AIF probe is part of the VIB assembly, typically located in the filter pan housing or filtration plumbing. Consult the wiring diagram in the FQ4000/M4000 service manual for the exact probe location.
Inspect the probe connector at the VIB board
Disconnect the AIF probe connector at the VIB board. Inspect the pins for corrosion, oil contamination, or bent contacts. Clean with electrical contact cleaner and reseat. Restore power to see if E37 clears.
Measure AIF probe resistance
With the probe disconnected, measure resistance across the probe leads. At room temperature (~70°F / 21°C), a healthy RTD reads approximately 109–115 Ω. Zero ohms indicates a short; OL indicates an open — replace the probe.
Inspect the harness for damage
Trace the probe wiring from the probe body to the VIB board. Look for oil-soaked insulation, pinched sections, or heat-damaged segments. Repair or replace any damaged harness section.
Replace the AIF RTD probe
Install an OEM replacement AIF probe. Apply thread sealant to the probe fitting if threaded into oil plumbing. Reconnect the harness, restore power, and verify E37 clears and AIF filtration cycles resume normally.
When to call a professional
Contact a Frymaster Authorized Servicer if E37 persists after replacing the AIF probe, indicating a VIB board probe-input fault. Also escalate if oil has infiltrated the probe conduit, requiring proper resealing of the probe fitting. Frymaster service: 1-800-551-8633.
Stop searching through PDFs. Our AI assistant on WhatsApp is trained on official Frymaster documentation and can diagnose this fault code and guide you through the repair in minutes.
5 free questions per bot in your browser — no signup.
Other Frymaster Error Codes
Temperature probe failure - RTD out of range
High limit 1 exceeded - vat temp above 410°F
High limit 2 exceeded - high limit switch opened
High limit problem - vat temp above 460°F, disconnect power immediately
Failed temperature probe or controller
Frypot temperature above 410°F
Heating problem / ignition lockout
Heating failure. The heating-control latch circuit failed, or the heat contactor failed to latch.
Heating failure - blower. The air pressure switch(es) failed to close.
Heating failure - pressure switch. The air pressure switch has failed closed. Call service.
Heating failure. The fryer failed to ignite and has locked out the ignition module.
Top-off probe failure. The ATO (auto top-off) RTD reading is out of range. Call service.
Sources: www.manualslib.com
AskWhiz Playground
Test your diagnostic skills
Play a real HVAC service call in the AskWhiz Playground — real brands, real fault codes, no signup.
Play a real service call