Repairs Removing The Front Panel And Top Panel; Overview Of Electrical Components; Overview Of Internal Components - Viessmann Vitocal 300-G Pro Installation And Service Instructions For Contractors

Repairs
Removing the front panel and top panel
1. Set the ON/OFF switch to OFF or 0 respectively.
2. Undo both screws on the underside of the front
panel.
!
3. Please note
The cables between the programming unit
and the wiring chamber can suffer damage.
Take care when removing the front panel
and observe the length of the cable (approx.
60 cm tolerance).
Put the front panel to one side and secure it
against falling over.

Overview of electrical components

See from page 31.

Overview of internal components

Fig. 36 Example (type BW 302.C140)
Wiring chamber
1
Safety high pressure switch, stage 1
2
Safety high pressure switch, stage 2
3
(only type BW 302.C090 to BW 302.C230)
Pressure transmitter, high pressure
4
Suction gas temperature sensor
5
Pressure transmitter, low pressure
6
Temperature sensor, liquid line
7
64
4. Carefully remove top panel (see page 50).
Electronic expansion valve (EEV) with stepper
8
motor
Hot gas temperature sensor, compressor 2
9
(only type BW 302.C090 to BW 302.C230)
Compressor 2
qP
(only type BW 302.C090 to BW 302.C230)
Hot gas temperature sensor, compressor 1
qQ
Compressor 1
qW