Viessmann Vitocal 300-G BW, Installation And Service Instructions Manual

Page: 122 / 216

122
ID Message (pri-
ority) 1. Cause
2. Measures Access right
BB KM BUS mixer
NC ("
U
")
1. Communication error KM BUS mixer
NC, internal fault extension set for one
heating circuit with mixer
2. Check appliance connections and cod-
ing
Customer
BC KM BUS FB
HK1 ("
U
")
1. Communication error KM BUS remote
control; heating circuit 1
2. Check appliance connections and cod-
ing; switch on appliance
Customer
BD KM BUS FB
HK2 ("
U
")
1. Communication error KM BUS remote
control; heating circuit 2
2. Check appliance connections and cod-
ing; switch on appliance
Customer
BE KM BUS FB
HK3 ("
U
")
1. Communication error KM BUS remote
control; heating circuit 3
2. Check appliance connections and cod-
ing; switch on appliance
Customer
C2 Power supply
monitor ("
U
")
1. Fault, power supply compressor, power
circuit; phase monitor faulty
2. Power supply, rotating field, asymme-
try, check for phase failure and compo-
nents
Customer
C5 Power-OFF
("i") 1. Power-OFF enabled
2. No measures required Customer
C9 Refrigerant cir-
cuit ("
U
")
1. Safety HP switch has responded
2. Check the flow and return temperature
sensors, check the primary and secon-
dary circuits for pressure and through-
put; ask your local refrigeration engi-
neer to check the heat pump, if
required.
(see also fault A9 on page 120)
Note
Switch appliance off and on after remov-
ing the cause for the message.
Customer
Troubleshooting
Control unit diagnostics
(cont.)
5368 522 UAE