Alto-Shaam E13

What does Alto-Shaam E13 mean?

E13 activates when the boiler temperature probe (B-4) reads above 248°F (120°C) for more than 25 seconds. This is a boiler high-temperature safety shutdown. Under normal operation the steam generator operates well below this threshold; exceeding it indicates a dry-boiler condition, a scaling problem, or a stuck steam element contactor.

Symptoms

• Oven halts and displays E13, especially during steam or combi modes.
• Steam output stops abruptly before the error appears.
• Scale or mineral deposits may be visible on the boiler probe or heating element.
• Error occurs repeatedly on units with hard water supplies and infrequent descaling.

Common causes

• Boiler operating dry due to a water supply or solenoid fault (related to E01 conditions).
• Heavy scale buildup on boiler elements causing localized overheating.
• Stuck or welded steam element contactor keeping elements on with no water present.
• Faulty boiler probe B-4 reading falsely high.
• Incorrect X-3 personality jumper or B-4 jumper position on ESi control models (per Alto-Shaam documentation).
• Plugged boiler drain preventing flush and refill.

Diagnostic steps

1. 01

   Verify water supply and boiler fill

   Confirm the water supply valve is open, inlet pressure is in range, and the solenoid valve fills the boiler correctly. An empty boiler with active elements is the fastest path to E13 and element burnout.

2. 02

   Inspect and descale the boiler

   If the boiler has not been descaled per the maintenance schedule, perform a descale procedure using Alto-Shaam–approved descaling solution. Heavy scale acts as insulation, causing element surface temperatures to far exceed the water temperature.

3. 03

   Test the boiler probe (B-4) resistance

   Disconnect probe B-4 and measure resistance; compare to the resistance-temperature curve in the service manual. An out-of-range reading at ambient temperature confirms a defective probe triggering a false E13.

4. 04

   Check the steam element contactor for welded contacts

   With power locked out, inspect the steam element contactor for welded contacts. A contactor that remains closed without a control signal will continue heating the boiler regardless of temperature.

5. 05

   Verify personality jumper settings (ESi models)

   On ESi-model units, confirm the X-3 personality jumper and B-4 jumper are installed in the correct positions per the wiring diagram for your model. Incorrect jumper placement causes the control to misinterpret probe readings and trigger E13.

When to call a professional

If the boiler ran dry and elements are visibly damaged, or if a stuck contactor or failed control board is identified, take the unit out of service and contact an Alto-Shaam authorized technician. Boiler element replacement and contactor work in the high-voltage compartment require certified service personnel.