02 01 Damaged or shorted DHW temperature probe

What the control is telling you

Applies to Combi models only. The controller uses the boiler return sensor in place of the DHW outlet sensor and keeps running CH and DHW.

Applies to: TRX150 (Combi models)

Likely causes

• Damaged or shorted DHW outlet probe
• Loose wiring

Test and repair steps

1. Check the DHW outlet temperature probe and wiring. Make sure the connections are secure.
2. Check the sensor resistance against Table 37 (not on these pages). Replace the sensor if it does not match.
3. If the problem continues, replace the main control.

Models that show this code

5 models in TRX

Other codes on the same units

• 1 16 Floor thermostat contact open
• 1 P1 Insufficient circulation or missing water (warning)
• 1 P2 Insufficient circulation or missing water (warning)
• 1 P3 Inadequate circulation or missing water (warning)
• 02 03 Storage temperature probe open or short circuit
• 02 05 DHW inlet probe open circuit
• 02 09 Storage overheating
• 2 P2 Anti-Legionella function not completely finished