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E04Convotherm

Convotherm E04

Connection area fan malfunction.

Source: Convotherm/CLE-OGB-10.10_iom.pdf

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What does Convotherm E04 mean?

E04 indicates a malfunction of the connection area fan. The manual attributes this to an auxiliary fan fault. This fan cools the electrical connection area of the combi, so when it fails the control flags E04 and the manual directs the remedy to customer service rather than an operator fix.

Symptoms

  • Display shows error code E04 for connection area fan malfunction
  • Auxiliary cooling fan does not run
  • Connection area may run warmer than normal

Common causes

  • Auxiliary fan fault

Diagnostic steps

  1. 01

    Confirm the error code

    Verify the display reads E04 connection area fan malfunction so the correct fan is addressed.

  2. 02

    Check for obvious obstruction

    Look for anything blocking the auxiliary fan area before assuming an internal fault.

  3. 03

    Power-cycle the unit

    Switch the combi off and back on to confirm the fault persists rather than being a one-time event.

  4. 04

    Call customer service

    The manual lists the remedy for the auxiliary fan fault behind E04 as calling customer service.

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When to call a professional

The manual lists an auxiliary fan fault as the cause of E04 and directs the remedy to customer service. Because the auxiliary fan protects the electrical connection area, a persistent E04 should be handled by a qualified Convotherm by Cleveland authorized service representative who can test and replace the fan safely.

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