Boiler leaking water from underneath the casing or onto the floor.

Safety: Switch off power and close the heating flow and return isolation valves. Place a tray under the boiler to catch drips.

• Remove front cover: Access the interior of the CTC boiler and inspect for visible signs of water trails or staining.
• Identify source: Check around the circulation pump, automatic air vent, pressure relief valve discharge, and all visible joints.
• Tighten joints: Carefully tighten any slightly weeping compression fittings. Do not overtighten plastic or cast components.
• Replace faulty parts (technician): If the leak is from the pump body, AAV, or heat exchanger, isolate, drain, and replace the component following CTC procedures.
• Dry and test: Once repaired, dry the base tray, repressurise the system, and monitor for further leaks.