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:
Connective pipe length
NOTE: N=2(one-twin models), N=3(
), N=4(one-four models), N=5(one-five models).
The Standard pipe length is 7.5m(25ft).
one-three models
Pre-charge pipe length(ft/m)
(Standard pipe lengthxN)
More than (Standard pipe lengthxN)ft/m
Air purging
method
Use vacuum
pump.
Use vacuum
pump.
Additional amount of refrigerant to be charged
(R410A)
AIR PURGING
Air purging
1
5
Liquid sid
e: 6.
35(1/4
"
)
(Total pipe length - standard pipe lengthxN)x15g(0.16o
z
)/m(ft)
Liquid sid
e:
9.52(3/8 ")
(Total pipe length - standard pipe lengthxN)x30g(0.32o
z
)/m(ft)
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.
Open the valve stem until it hits against the
stopper. Do not try to open it further.
Securely tighten the valve stem cap with a
spanner or the like.
Valve stem cap tightening torque (See
Tightening torque table in previous page ).
Outdoor
unit
Indoor
unit
Refrigerant
Flare nut
Stopper
Cap
Valve body
Packed valve
Half union
Gas side
Liquid side
A
C
D
B
Valve stem
Fig.
1
6
Fig.
1
7
Caution in handling the packed valve
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.
Summary of Contents for 18k
Page 19: ...NOTES...
