Replacing The Hmi Connecting Cable; Checking The Plate Heat Exchanger - Viessmann B0KA Installation And Service Instructions Manual

Troubleshooting
Repairs
(cont.)

Replacing the HMI connecting cable

!
Please note
Incorrect routing of the cable can lead to heat
damage and impairment of the EMC properties.
For positioning and securing of the cable (fixing
point of the cable tie) see connecting cable
installation instructions.

Checking the plate heat exchanger

A
D
2.
Fig. 41
Heating water flow
A
Heating water return
B
Cold water
C
DHW
D
1. Shut off and drain the boiler on the heating water
and DHW sides.
2. Undo screws.
3. Remove plate heat exchanger.
Note
During and after removal, small amounts of water
may trickle from the plate heat exchanger.
4. Remove gaskets and dispose of them.
76
B
C
4.
5. Check connections on the DHW side for scaling.
Clean or replace the plate heat exchanger as
required.
6. Check connections on the heating water side for
contamination. Clean or replace the plate heat
exchanger as required.
3.