Viessmann VITODENS 200-W Service Instructions Manual page 81

Repairs
(cont.)
Checking the plate heat exchanger
A
B
F G
F Heating return
G Cold water
H Heating flow
K DHW
1. Shut off and drain the boiler on its
heating water and DHW side.
2. Release the side closures and pivot
the control unit forward.
3. Pull the leads from comfort sensor
A.
4. Remove the retaining clip and siphon
B.
5. Remove thermal insulation C.
6. Undo screws D and remove plate
heat exchanger E through the
front.
EDC
Note
During removal, small amounts of
water may trickle out and escape
from the plate heat exchanger.
7. Check the DHW side for scaling and,
if required, clean or replace the plate
heat exchanger.
H K
8. Check the heating water side for con-
tamination and, if required, clean or
replace the plate heat exchanger.
9. Install in reverse order with new gas-
kets.
10.
Troubleshooting
Danger
Escaping gas leads to a risk
of explosion.
Check gas equipment for
tightness.
81