Tekno Point Multisplit air conditioner, Installation Manual

Page: 35 / 40

34
ENGLISH
8. INSTALLATION
Indoor unit
Outdoor unit
Manifold gauge
Pressure
gauge
Charge hose
Nitrogen gas cylinder
(in vertical position)
Air purging
Air and moisture in the refrigerant system have undesirable effects as indicated
below:
• Pressure in the system rises.
• Operating current rises.
• Cooling or heating efficiency drops.
• Moisture in the refrigerant circuit may freeze and block capillary tubing.
• Water may lead to corrosion of parts in the refrigeration system.
Therefore, the indoor unit and tubing between the indoor and outdoor unit must be
leak tested and evacuated to remove any noncondensables and moisture from the
system.
Air purging with vacuum pump
• Preparation
Check that each tube (both liquid and gas side tubes) between the indoor and
outdoor units have been properly connected and all wiring for the test run has
been completed. Remove the service valve caps from both the gas and the liquid
side on the outdoor unit.
Note that both the liquid and the gas side service valves on the outdoor unit are
kept closed at this stage.
• Pipe length and refrigerant amount:
• When relocate the unit to another place, perform evacuation using vacuum
pump.
Make sure the refrigerant added into the air conditioner is liquid form in any case.
Caution in handling the packed valve
• Open the valve stem until it hits against the stopper. Do not try to open it further.
• Securely tighten the valve stem cap with aspanner or the like.
• Valve stem cap tightening torque (See Tightening torque table in previous page).
When Using the Vacuum Pump
(For method of using a manifold valve, refer to its operation manual.)
1. Completely tighten the flare nuts, A, B, C, D, connect the manifold valve charge
hose to a charge port of the low-pressure valve on the gas pipe side.
2. Connect the charge hose connection to the vacuum pump.
3. Fully open the handle Lo of the manifold valve.
4. Operate the vacuum pump to evacuate. After starting evacuation, slightly loose
the flare nut of the Lo valve on the gas pipe side and check that the air is ente
ring (Operation noise of the vacuum pump changes and a compound meter indi
cates 0 instead of minus)
5. After the evacuation is complete, fully close the handle Lo of the manifold valve
and stop the operation of the vacuum pump.
Make evacuation for 15 minutes or more and check that the compound meter
indicates -76cmHg(-1x105Pa).
6. Turn the stem of the packed valve B about 45°counterclockwise for 6-7 seconds
after the gas coming out, then tighten the flare nut again. Make sure the pressu
re display in the pressure indicator is a little higher than the atmosphere
pressure.
7. Remove the charge hose from the Low pressure
charge hose.
8. Fully open the packed valve stems B and A.
9. Securely tighten the cap of the packed valve.
Indoor unit
Outdoor unit
Pressure
gauge
Manifold gauge
Open
Close
Vacuum pump