Viessmann AWS 104, Installation And Service Instructions For Contractors

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71
3. Make all connections, as shown
above.
!
Please note
Connect filling hose end with
valve port to the service valve
in the internal unit
last .
For all connections, counter-
hold with a second open-
ended spanner.
4. Start the vacuum pump.
At the pressure gauge set, open the
valve to the vacuum pump and the
valve to the hot gas connection.
5. After approx. 5 min, open the valve to
the vacuum gauge.
Leave the vacuum pump running until
almost 0 bar is indicated on the vac-
uum gauge (at least 30 min).
Note
The vacuum pump runtime will
depend on the ambient conditions.
6. Close the valve on the pressure
gauge set to the vacuum pump.
Stop the vacuum pump and wait
approx. 5 min. There is a leak if the
indication on the vacuum gauge
rises.
Remove the leak and repeat the proc-
ess.
7. Close all valves at the pressure
gauge set.
8. Remove the vacuum pump and vac-
uum gauge.
Filling the refrigerant lines and internal unit
Note
■ The external unit is pre-filled with
refrigerant R410A.
■ No topping up is required for line
lengths up to 12 m.
■ Max. length of refrigerant lines: 30 m.
■ The refrigerant mixture R410A must
be topped up only in a liquid state.
■ Topping up is only possible in cooling
mode (see separate service instruc-
tions, heat pump control unit).
Danger
Direct contact with refrigerant
can harm skin.
Wear safety goggles and protec-
tive gloves when working on the
refrigerant circuit.
Commissioning, inspection, maintenance
Further details regarding the individual steps
(cont.)
5724 152 GB
Service