C System, Operating After Filling Refrigerant Circuit - Audi Q7 2007 Repair Manual

Audi Q7 2007 ➤
Heating, Ventilation and Air Conditioning - Edition 04.2013
21 A/C System, Operating after Filling
Refrigerant Circuit
Note
Only start engine after refrigerant circuit has been assembled.
♦
If possible start engine only with a filled refrigerant circuit.
♦
Do not start the engine while evacuating the refrigerant circuit
♦
or when the circuit is already evacuated (the A/C compressor
could be damaged). Refer to ⇒ A/C System with Refrigerant
R134a; Rep. Gr. 87 ; Refrigerant Circuit (A/C System with
Refrigerant R134a; Refrigerant Circuit, Using Service Station).
Compressor is always driven by the pulley or by the driveshaft
♦
(there is no magnetic clutch). To prevent damage when the
compressor is idling, it is lubricated by an "internal oil circuit".
The compressor has an "internal oil circuit" to ensure the com‐
♦
pressor is not damaged when refrigerant circuit is empty.
Prerequisite for the internal lubrication is residual refrigerant
oil in compressor.
The engine may only be started when the refrigerant circuit is
♦
Protected by copyright. Copying for private or commercial purposes, in part or in whole, is not
installed correctly. If for example the refrigerant lines are not
permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
connected to the compressor and the engine is started then
with respect to the correctness of information in this document. Copyright by AUDI AG.
the compressor may be destroyed by the build-up of internal
heat.
The A/C Compressor Regulator Valve - N280- is not activated
♦
when the refrigerant circuit is empty and the compressor idles
with the engine. As there is no refrigerant in the circuit the oil
required to lubricate is not fed to the compressor.
♦ All removed parts are in again.
♦ The refrigerant circuit is filled. Refer to ⇒ A/C System with
Refrigerant R134a; Rep. Gr. 87 ; Refrigerant Circuit (A/C Sys‐
tem with Refrigerant R134a; Refrigerant Circuit, Using Service
Station).
If it is necessary to start the engine with a discharged refrigerant
circuit:
♦ Refrigerant circuit must fully assembled.
♦ There must be no vacuum in the refrigerant circuit.
♦ At least a quarter of the specified refrigerant oil must be in the
compressor.
♦ Do not let the engine RPM go above 2,500.
♦ The engine should only run as long as absolutely necessary.
Note the following when starting engine for first time after filling
refrigerant circuit:
– Follow the information about starting the A/C system after in‐
stalling the compressor. Refer to ⇒ A/C System with Refrig‐
erant R134a; Rep. Gr. 87 ; A/C System General Information
(A/C System with Refrigerant R134a; A/C System, General
Information).
– Start engine with the compressor turned off ("ECON" mode
set, the indicator lamp in the
indicator lamp in the
the engine idle speed has stabilized.
– Open all instrument panel vents.
332
Rep. Gr.87 - Air Conditioning
button turns on and the
ECON
button does not turn on) and wait until
AC