Specifications
EDUS04-740 Installation Manual
Room Air Conditioners D-Series 51
Outdoor Unit Installation
• If adding additional refrigerant, perform air purging from the
refrigerant pipes and indoor unit using a vacuum pump before
charging additional refrigerant.
• Use a hexagonal wrench (3/16”) to operate the shut-off valve rod.
• All refrigerant pipe joints should be tightened with a torque wrench to
the specified tightening torque.
5. Purging Air and Checking for Gas Leakage
• When the piping work is completed, it is necessary to purge the air and check for gas leakage.
1) Do not place any substance other than the specified refrigerant (R410A) into the refrigeration cycle.
2) When a refrigerant gas leak occurs, ventilate the room as soon and as much as possible.
3)
R410A, as well as other refrigerants, should always be recovered and never be released directly into the environment.
4) Use a vacuum pump for R410A exclusively. Using the same vacuum pump for different refrigerants may
damage the vacuum pump or the unit.
Warning
3) Do vacuum pumping and make sure that the vacuum pressure gauge reads – 29.9 inHg *1.
4) Close gauge manifold's low-pressure valve (Lo) and stop vacuum pump.
(Keep this state for a few minutes to make sure that the vacuum pressure gauge pointer does not swing back.)
*2
.
1) Connect projection side (on which worm pin is pressed) of charging hose (which comes from gauge manifold) to gas
shut-off valve’s service port.
2) Fully open gauge manifold’s low-pressure valve (Lo) and completely close its high-pressure valve (Hi).
(High-pressure valve subsequently requires no operation.)
5) Remove covers from liquid shut-off value and gas shut-off valve.
6) Turn the liquid shut-off valve’s rod 90 degrees counterclockwise with a hexagonal wrench to open valve.
Close it after 5 seconds, and check for gas leakage.
Using soapy water, check for gas leakage from indoor unit’s flare and outdoor unit’s flare and valve rods.
After the check is complete, wipe all soapy water off.
7) Disconnect charging hose from gas shut-off valve’s service port, then fully open liquid and gas shut-off valves.
(Do not attempt to turn valve rod beyond its stop.)
8)
Tighten valve lids and service port caps for the liquid and gas shut-off valves with a torque wrench at the specified torques.
Compound
pressure gauge
Pressure
meter
High-
pressure
valve
Low-pressure
valve
Vacuum pump
Service port
Liquid
shut-off
valve
Valve lids
Gas shut-off valve
Charging
hoses
Gauge
manifold
*1. Pipe length vs. vacuum pump run time
*2. If the vacuum pressure gauge pointer swings back, refrigerant may have water content or a loose pipe joint
may exists. Check all pipe joints and retighten nuts as needed, then repeat steps 2) through 4).
Pipe length Up to 50 feet More than 50 feet
Run time Not less than 10 min. Not less than 15 min.