BoilerFaultCodesWhat the manual says
Manufacturer manualCH limit thermostat (50) open circuit (pump will run) or DHW limit thermostat (52) open circuit
From this model's manual
Verified against the Ferroli Boiler Optima 201 installation & service manual.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Related fault codes
All 42 fault codes on the Optima 201
Seeing a different code? Every code this model can display, in one place.
Display FlashingGreen LED onLED 1 green (0)LED 1: 0LED 2 (C.H.)LED 2 (CH)LED 2 (D.H.W.)LED 2 (DHW)LED 2 yellow (0) [DHW mode]LED 2 yellow (1) [CH mode]LED 2: 0LED 2: 1LED 3 (CH)LED 3 yellow (0) [CH mode]LED 3: 0LED 4 (C.H.)LED 4 (CH)LED 4 (D.H.W.)LED 4 (DHW)LED 4 green (0) [CH mode]LED 4 green (0) [DHW mode]LED 4: 0LED 4: 0 (Central Heating)LED 5 (CH)LED 5 (DHW)LED 5 red (1) [CH mode]LED 5 red (1) [DHW mode]LED 5: 1LED 5: 1 (Central Heating)LED 6 (C.H.)LED 6 (CH)LED 6 (D.H.W.)LED 6 (DHW)LED 6 yellow (0) [CH mode]LED 6 yellow (0) [DHW mode]LED 6: 0LED 6: 0 (Central Heating)LED 7 green (0)LED 7: 0Orange LED onRed LED on/Flashing