Viessmann Vitocal 242-S Installation And Service Instructions Manual page 73

Further details regarding the individual steps
Example: type AWT-AC 241.A07
A Internal unit
B External unit
C Liquid line
D Fill valve
Commissioning, inspection, maintenance
(cont.)
E Service valve (Schrader valve)
For type AWT-AC, type 241.A07,
the service valve is located at the
connection of the liquid line.
F Hot gas line
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