Ariston 101 Fault

Ariston 101 Fault

The Ariston error code 101 indicates an overheating problem within the boiler. This fault arises when the boiler’s internal temperature exceeds the maximum safe limit. It’s a critical error because it can indicate a serious malfunction that, if not addressed, could lead to further damage to the boiler or pose safety risks.

Causes of Error Code 101

  1. Faulty Thermostat: If the thermostat is malfunctioning, it may not correctly regulate the boiler’s temperature, leading to overheating.
  2. Blocked Heat Exchanger: Scale or sludge buildup in the heat exchanger can restrict water flow, causing the water to overheat.
  3. Pump Failure: A failing or seized pump can’t circulate water properly, resulting in localized overheating within the boiler.
  4. Restricted Water Flow: Closed or partially closed valves, as well as blockages in the system, can reduce water flow, leading to overheating.
  5. Airlocks: Air trapped in the system can prevent proper water circulation, causing hot spots and overheating.

Troubleshooting and Resolving Error Code 101

  1. Reset the Boiler: Initially, try resetting the boiler to see if the error clears. Sometimes, the system simply needs a reset to resume normal operation.
  2. Check the Thermostat: Ensure the thermostat is functioning correctly. A faulty thermostat may require replacement.
  3. Inspect the Heat Exchanger: Look for signs of scale or sludge buildup in the heat exchanger. A professional cleaning might be necessary.
  4. Evaluate the Pump: Listen for any unusual noises from the pump that might indicate it’s failing. A non-operational pump will need to be repaired or replaced by a professional.
  5. Ensure Proper Water Flow: Check valves to ensure they are fully open and bleed radiators to remove any airlocks in the system.
  6. Professional Assistance: Given the potential complexity and safety concerns associated with overheating issues, it’s advisable to seek help from a qualified heating engineer. A professional can accurately diagnose and safely repair issues causing the boiler to overheat.
  7. Regular Maintenance: To prevent future occurrences of error code 101 and other boiler issues, ensure your heating system receives regular maintenance and servicing. This can help identify and address potential problems before they lead to serious malfunctions.


The Ariston error code 101 signifies an overheating issue that requires immediate attention. While some preliminary checks can be done by the homeowner, diagnosing and fixing the underlying cause of overheating often necessitates professional intervention. Regular boiler maintenance is essential for preventing such issues, ensuring the system operates safely and efficiently.