BoilerFaultCodesAriston 7 01 Fault Code
Also written as 701 — same fault.
The Ariston 7 01 fault code means: your boiler is struggling to read the temperature for a secondary heating zone, meaning that specific part of your home may not heat up correctly.. It appears on 13 Ariston models in our database.
Technical description: Zone 2 outgoing sensor defective
What causes the Ariston 7 01 fault?
This fault occurs when the internal sensor responsible for monitoring the temperature of the water leaving the boiler for your central heating stops sending a reliable signal. The most common reason is that the sensor has developed an electrical fault or has been damaged by wear and tear, meaning the boiler can no longer safely regulate your heating. In some cases, loose or damaged wiring between this sensor and the main control board can also trigger the error.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Ariston models that show the 7 01 fault code
Click a model for the full fault code list and model-specific repair notes.
- Challenger 80E Repair: £120-220
- Clas HE 24 Repair: £120-220
- Clas HE 28 Repair: £120-220
- Clas HE 35 Repair: £120-220
- Clas HE Evo Repair: £120-220
- Clas Net One Repair: £120-200
- Clas One Repair: £120-200
- Clas System 28 Repair: £120-200
- E-Combi Evo Repair: £120-220
- E-Combi One Repair: £120-220
- E-Combi One 24 Repair: £90-160
- E-Combi One 30 Repair: £120-220
- Microsystem 15 Repair: £120-220
Source
Ariston 7 01 fault code information on this page is sourced and cross-checked against the official Ariston service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026