Airwell AWAU-YDV1010-H13, Service Manual

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(E) Upon confirmation via the procedures from (A) to (D), if the pressure is low, the leakage exists.
Check welding part, flaring part, etc. with foam test solution, find out leakage and repair it. Test the air-
tightness again after the repair.
Attention
Prevent excessive pressurizing, or nitrogen may access outdoor unit.
Make sure to conduct vacuum pumping after the airtight test.
Nitrogen
Airtight (pressurization) pipe
To indoor unit
Instrument manifold
Operating valve Operating valve
Liquid pipe Liquid pipe
Balancing oil
pipe
Outdoor unit 1 Outdoor unit 2
Balancing oil
pipe
Gas pipe Gas pipe
Service port (check
interface)
Lo
handle
Hi
handle
Attention
Perform vacuum pumping to
balancing oil pipe as well.
(2) Vacuum pumping
Carry out vacuum pumping from the check interface of operating valve at liquid side and from both sides of
operating valve at gas side.
Make sure to perform vacuum pumping for balancing oil pipe as well. (Use the check interface of balancing oil
pipe's operating valve separately.)
<Workflow>
Airtight test ends
Vacuum pumping begins Vacuum pumping ends
Check the vacuum degree
(charge additional refrigerator oil)
Seal in refrigerant
When reaching below-101
kPa (below -755 mmHg),
let the vacuum pump run
continuously for more than
1 h.
Leave it alone for more
than 1 h to make the
vacuum meter pointer not
rise
A rising vacuum meter pointer indicates there is residual moisture or water
leakage inside the system.
Check and repair the leakage part before another vacuum pumping.
Attention
When vacuum degree is insufficient, blockage will result from inadequate capacity, residual moisture, etc., thus
leading to compressor fault.