Viessmann Vitoplus 300 Service Instructions Manual page 81

Wall mounted oil fired condensing boiler for the combustion of low sulphur fuel oil din 51603-el-1 with integral boiler control unit

Table of Contents

Repairs

(cont.)

Replacing the air vent valve

1. Removing the burner (see

page 21).

2. Drain the primary side of the boiler

system, until the pressure gauge

indicates "0".

3. Grip the silencer and remove safety

spring A.

4. Remove air vent valve B with

intermediate piece C by pulling it

upwards.

5. Unscrew air vent valve B from

intermediate piece C.

6. Fit new air vent valve B onto inter-

mediate piece C.

7. Push air vent valve B with inter-

mediate piece C into the heat

exchanger.

8. Push on retaining spring A. Check

with a hand mirror for correct seat-

ing.

9. Assemble the boiler in reverse

order and fill from the primary side.

Troubleshooting

Table of Contents

Vp3a