Actuator or cartridge only?

Diagnose first: manually push the actuator pin. If it moves freely, replace the actuator only; if the pin sticks, the cartridge is scaled.

A brass spanner or the OEM diverter tool avoids cracking the plastic body on ATAG i36 Combi.

Do I need to notify the manufacturer?

Only if the ATAG i36 Combi is in warranty — ATAG require log of any part swap for labour claims.

Replace the diverter valve on ATAG i36 Combi when hot water runs cold on demand or the boiler cycles between CH and DHW.

Drain to below the diverter body via the CH drain-off. On ATAG i36 Combi the diverter is a cartridge design — pull the retaining clip and lift out.

Fit new O-rings, silicone-grease the cartridge and align the actuator drive slot before refitting the motor.

Refill the ATAG i36 Combi to 1.2 bar cold. Bleed high-point radiators and the internal AAV.

Run a full flue-gas analysis after 15 minutes. Log the reading against the OEM commissioning envelope in the Benchmark book.

Actuator or cartridge only?: Diagnose first: manually push the actuator pin. If it moves freely, replace the actuator only; if the pin sticks, the cartridge is scaled.
Any special tools?: A brass spanner or the OEM diverter tool avoids cracking the plastic body on ATAG i36 Combi.
Do I need to notify the manufacturer?: Only if the ATAG i36 Combi is in warranty — ATAG require log of any part swap for labour claims.

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