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Hot water temperature too low

Hot water temperature too low — Hot water is not hot enough

Worcester Bosch · Greenstar Boilers

What does Hot water temperature too low mean?

The hot water produced by the boiler is not reaching the desired or expected temperature, making it unsuitable for use.

Common Causes

  • Programmer setting
  • Cylinder thermostat set too low

Repair Steps & Checklist

Click steps to track your progress.

  1. 1

    Check the programmer setting for hot water to ensure it's active and set for the desired times.

  2. 2

    Adjust the cylinder thermostat to a higher temperature setting.

  3. 3

    Allow sufficient time for the hot water cylinder to heat up after any adjustments.

Browse all codes in this manual (12)
Verified technical data. Last updated: April 2026

Related Faults

Blue light Fast flashBlue light Fast flash — Hot water not working (central heating OK)Blue light Fast flash 2 pulsesBlue light Fast flash with 2 pulses — Boiler not responding to any demandBlue light Fast flash 5 pulses, Reset button FlashingBlue light Fast flash with 5 pulses, Reset button Flashing — Ignition lockout
Source: Worcester Bosch Greenstar Boilers
Open Manual (Page 87)Search more codes in this manual