Overview Of Internal Components: Internal Unit - Viessmann Vitocal 200-S Installation And Service Instructions Manual

Maintenance

Overview of internal components: Internal unit

C
B
A
Fig. 53
Overview of internal components: External unit
Danger
Contact with 'live' components can lead to seri-
ous injury from electric current. Some compo-
nents on PCBs remain 'live' even after the
power supply has been switched off.
When working on the external unit, isolate the
■
system from the power supply, e.g. at a sepa-
rate MCB/fuse or a mains isolator. Check the
system is no longer 'live' and safeguard
against reconnection.
■ Prior to working on the appliance, wait at
least 4 min until the voltage has completely
dropped out.
62
Secondary circuit flow temperature sensor
?
Secondary circuit return temperature sensor
aJ
Secondary pump
sG
D 3-way diverter valve for "Central heating/DHW
lJ
heating"
E
A Liquid gas temperature sensor (IRT)
Condenser
B
F
Pressure sensor (ITC) for determining condensa-
C
tion temperature in condenser
Flow temperature sensor, secondary circuit
D
upstream of instantaneous heating water heater
(LWT)
Secondary circuit air vent valve
E
G
High limit safety cut-out for the instantaneous heat-
F
ing water heater
Instantaneous heating water heater
G
Drain & fill valve, secondary circuit
H
aJ
?
lJ
sG
H