Midea MCH2U-18PHH2, Руководство по обслуживанию

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11
4.4 First-Time Installation
Air and moisture in the refrigerant system
cause the following problems:
●
Increases in system pressure
●
Increases in operating current
●
Decreases in cooling and heating
efficiency
●
Blocks in capillary tubing caused by
moisture in the refrigerant circuit freezing
●
Corrosion of parts in the refrigerant
system caused by water
The indoor units and the pipes between
indoor and outdoor units must be tested for
leakages and evacuated to remove gas and
moisture from the system.
Gas leak check with soap water:
Apply soap water or a liquid neutral
detergent on the connections with a soft
brush to check for leakage in the pipe
connecting points. If bubbles emerge, the
pipes are leaking.
1. Air Purging Using the Vacuum Pump
1. Completely tighten the flare nuts on the
indoor and outdoor units. Confirm that
both the2-way and 3-way valves are set
to the closed position.
2. Connect the charge hose with the push
pin of the Handle Lo to the 3-way valve
gas service port.
3. Connect the charge hose of the Handle
Hi to the vacuum pump.
4. Fully open the Handle Lo of the manifold
valve.
5. Turn on the vacuum pump to begin
evacuation.
6. Conduct a 30-minute evacuation. Check
whether the compound meter indicates -
0.1Mpa(14.5Psi). If the meter does not
indicate
-0.1Mpa(14.5Psi) after 30
minutes has elapsed, continue
evacuation for 20 more minutes. If the
pressure
does not reach -
0.1Mpa(14.5Psi) after 50 minutes has
elapsed, check if there are any leaks.
Fully close the Handle Lo valve of the
manifold valve and turn off the vacuum
pump. After 5 minutes, confirm that the
gauge needle is not moving.
7. Turn the flare nut on the 3-way valve45°
counterclockwise for 6-7 seconds. Once
gas begins to come out, tighten the flare
nut. Make sure the pressure display on
the pressure indicator is higher than
atmospheric pressure. Then remove the
charge hose from the 3-way valve.
8. Fully open the 2-wayand 3-way valves
and securely tighten the cap on the 3-
way valve.
2. Adding refrigerant if the pipe length
exceeds chargeless pipe length
Procedure: