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Room temp fluctuations

Excessive room temperature fluctuations

Worcester Bosch · Greenstar CDi Boilers

What does Room temp fluctuations mean?

The room temperature varies significantly, rising and falling beyond comfortable levels, even with the heating system active.

Common Causes

  • Temporary effect of heat from other sources on the room (e.g., sunshine, room lighting, TV, fireplace).

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Observe if external heat sources like direct sunlight, lighting, TV, or a fireplace are temporarily influencing the room temperature.

  2. 2

    If the FW 100 room control unit is affected by these, choose a better installation location for it.

  3. 3

    Minimize the impact of temporary heat sources where possible.

Browse all codes in this manual (55)
Verified technical data. Last updated: April 2026

Related Faults

1A4 E1A4 E displayed — Temperature sensor in FW 100 defective1A8 E1A8 E displayed — Bus communication error with TD 200 or heating applianceA7 EA7 E displayed — General fault in the heating appliance
Source: Worcester Bosch Greenstar CDi Boilers
Open Manual (Page 68)Search more codes in this manual