York YEFE BZTM-MOW1 Series Service Manual page 26

Procedure:
1. Tighten the flare nuts of the indoor and outdoor units, and confirm that both the 2- and 3-way valves are closed.
2.
Connect the charge hose with the push pin of Handle Lo to the gas service port of the 3-way valve.
3. Connect another charge hose to the vacuum pump.
4. Fully open the Handle Lo manifold valve.
5. Using the vacuum pump, evacuate the system for
30 minutes.
a. Check whether the compound meter indicates -0.1 MPa (14.5 Psi).
• If the meter does not indicate -0.1 MPa
(14.5 Psi) after 30 minutes, continue
evacuating for an additional 20 minutes.
• If the pressure does not achieve -0.1 MPa
(14.5 Psi) after 50 minutes, check for leakage.
• If the pressure successfully reaches -0.1 MPa (14.5 Psi), fully close the Handle Lo valve, then cease vacuum
pump operations.
b. Wait for 5 minutes then check whether the gauge needle moves after turning off the vacuum pump. If the
gauge needle moves backwards, check whether there is gas leakage.
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