Haier AU482FIBHA Service Manual page 44

8.9 Test of leakage after wiring work is finished
After connection of the refrigerant pipes, carry out leakage test. In this test,
pressurize to the pipes as shown in the below figure by using nitrogen tank.
Close the valves of the gas side and liquid side totally.
The nitrogen may enter the cycle system of the outdoor unit, so that, before pressurizing, the
valve rods must be fastened. (Both the gas side and liquid side).
For each of the refrigerant system, pressurize from the discharge valve of gas side in
procedure.
When doing leakage test, it is absolutely forbidden to use oxygen, flammable gas and
poisonous gas. The indoor unit expansion valve must be
After wiring work and setting the address, switch on the indoor units and
after 25-30s put down the power,then charge the nitrogen gas.
5 vacuuming of the pipes and indoor unit (using vacuum pump to vacuums, it is strictly forbidden to use
refrigerant purging)
a. Choose of vacuum pump: it shall choose those that can reach a good vacuity (over 200Pa)and have
a large air discharge amount (over 40L/min).
b. After finishing the airtight quality test and the nitrogen discharging , connect the instrumental diverter
to the 3-way discharge valve, then connect the vacuum pump according to the below figure.
open.