BoilerFaultCodesWhat the manual says
Manufacturer manualCommunication error, programming unit
From this model's manual
Verified against the Viessmann/Viessmann Vitodens 200 W B2ha 49 60 5817254 installation & service manual.
DIY fix possible
Turn the boiler off at its on/off switch and at the mains fuse or isolator, then wait 2 to 3 minutes.Switch the power back on and wait about 5 minutes for the boiler to fully start up.Check the display: if the b1 code has cleared and the boiler heats water and responds to the thermostat, no further action is needed.If b1 returns, stop and contact a Gas Safe registered engineer, as the cable or control unit may need inspecting.
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Related fault codes
All 82 fault codes on the Vitodens 200-W B2HA-60
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