Toshiba MM-A0160HX, Service Manual

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17
Refrigerant Pipe Installation
Additional Refrigerant Charging Method
(1) Loosely connect the refrigerant cylinder hose to the gauge manifold, then open the source
valve V
H
on the cylinder, purge the air in the hose, and then tighten the hose.
(2) As shown in the diagram below, turn the refrigerant cylinder upside down, open the valve
V
H
on the gauge manifold, and then charge the liquid side pipe with refrigerant in the
liquid state. (Note that with some types of refrigerant cylinders, the liquid refrigerant will be
output through siphoning action with the cylinder in the normal upright position.) If the
proper charging amount cannot be reached, close the valve V
H
, turn the refrigerant cylinder
upright, open the liquid-side and balance packed valves completely, and open the gas-side
packed valve only half way. Begin the cooling operation, open valve V
L
, and then charge
the gas-side pipe with refrigerant in the gaseous state.
(3) While watching the scales display, quickly close the valve V
L
completely when the system
has been charged with the proper amount of additional refrigerant. Then close the source
valve Va on the cylinder, and open the gas-side packed valve completely.
(4) Record the amount of additional refrigerant that was added to the system on the nameplate
inside the front panel (lower) of the outdoor unit.
4.5 5.5 7.0
Detailed drawing of packed valve
To gauge
manifold
{
Service port
at liquid side
Packed valve
at liquid side
Service port at
balance side
Packed valve
at balance side
Piping
at site
Service port
at gas side
Packed valve
at gas side
Piping at site
Piping
at site
To main unit
To main
unit
To main
unit
Indoor Unit
Packed valve (Gas side)
Outdoor Unit
Service
port
Gauge manifold
Refrigerant
gas
Refrigerant
bottle
Scales
Low
pressure
High
pressure
Gas pipe
Liquid pipe
V
L
V
H
Va
Gas
Liquid