Fault Codes - Viessmann Vitocrossal 300 CA3 2.5 Installation And Service Instructions Manual

Vitocrossal 300 CA3 Series 2.5 to 6.0 Installation/Service

Fault Codes

General process faults
Fault display on the programming unit of the burner.
Note: Carry out measures in the described order. All fault
codes are saved to the fault memory and the last
10 can be called up.
Displayed System Characteristics
Fault Code
Burner control unit in a fault
F 80
state; system cools down;
burner control unit locked out
Burner control unit in a fault
F 81
state
Burner control unit in a fault
F 82
state; system cools down;
burner control unit locked out
Burner control unit in a fault
F 83
state
Burner control unit in a fault
F 88
state
Burner control unit in a fault
F 89
state
Burner control unit in a fault
F b7
state; system cools down;
burner control unit locked out
Type of coding card
F b7
Burner control unit in a fault
F d0
state
Gas pressure switch 2, GDW2
F E1
activated (closed on pressure
rise)
Gas pressure switch 2, GDW2
F E2
did not close during control self
diagnostics
Shortage of gas to gas pressure
F E2
switch 2; valve leak test
Cause
Short circuit, boiler water
temperature sensor, burner
control unit
Sensor drift, boiler water
temperature sensor, burner
control unit
Short circuit, secondary boiler
water temperature sensor
(A or B), burner control unit
Sensor drift, secondary boiler
water temperature sensor
(A or B), burner control unit
Lead break, boiler water
temperature sensor, burner
control unit
Lead break, secondary boiler
water temperature sensor
(A or B), burner control unit
Coding card not inserted
in the burner control unit;
incorrect or faulty coding card
Coding card does not match
burner control unit
Simultaneous selection of
multiple gas types at the
burner control unit via plug lÖ
1st gas valve seat leaking/
GDW2. Gas pressure switch 2
activated/burner test firing
valve closed.
Gas valve does not open, gas
valve leaking, gas pressure
switch faulty
Gas valve does not open;
gas valve leaking; gas
pressure switch 2 faulty.
Burner Control Unit
Measures
Check lead and dual sensor;
replace sensor if required
Check lead and dual sensor; replace
sensor if required
Check lead and sensors (A and B),
replace sensor if required
Check lead and sensors (A and B),
replace sensor if required
Check lead and dual sensor; replace
sensor if required
Check lead and sensors (A and B),
replace sensor if required
Insert coding card; check coding card;
replace if required
Replace coding card or burner control
unit
 Danger Plug-in terminals on the
burner control unit are 'live'. Only
replace the coding card when the
power has been isolated from the
burner control unit (via the internal
power disconnect inside the GW6C).
Check line, check wiring, replace
burner control unit, if required.
Check setting of gas pressure
switch 2; check connecting cable;
replace gas valve.
Check setting of gas pressure
switch 2; check connecting cable;
replace gas valve
Replace gas valve
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