Check Fixed High Limit; Check Fuse; Check Fuses In The Power/Pump Module - Viessmann VITODENS 200-W WB2B Start-Up/Service Instructions

Troubleshooting
Corrective Action
A
Fig. 23
A
Fig. 24
64
(continued)

Check fixed high limit

Check the fixed high limit, if the burner control cannot be reset after a fault
shutdown, although the boiler water temp. is below approx. 75 °C / 167 °F:

Check fuse

F1

Check fuses in the power/pump module

1. Remove cables from the fixed high
limit A.
2. Check the continuity of the fixed
high limit with a multimeter.
3. Remove and replace a defective
fixed high limit.
4. After starting up the boiler, press "
RESET" on the boiler control.
1. Switch OFF the power.
2. Release side latches and
pivot the control unit down.
3. Remove cover A.
4. Check fuse F1 (see wiring diagram).
1. Switch OFF the power.
2. Open power/pump module and check
fuses F1 and F2 (see wiring
diagram).