4CONTROL

[1] Control of Outdoor Unit

(1) Initial processing
•When turning on power source, initial processing of microcomputer is given top priority.
• During initial processing, control processing corresponding to operation signal is suspended. The control processing
is resumed after initial processing is completed. (Initial processing : Data processing in microcomputer and initial
setting of each LEV opening, requiring approx. 2 minutes at the maximum.)
(2) Control at staring
• In case unit is started within 2 hours after turning on power source at low outdoor air temperature (+5˚C (41°F) or
less), the unit does not start operating for 30 minutes at the maximum .
(3) Bypass, capacity control
•Solenoid valve consists of bypass solenoid valve (SV1, SV2) bypassing between high pressure side and low pres-
sure side. The following operation will be provided.
1) Bypass solenoid valves SV1 and SV2 (both "open" when turned on)
SV1
ON (Open) OFF (Close)
Turned on for 4 minutes
Turned on for 2 minutes
Always turned on
Turned on for 3 minutes
Always turned on
Always turned on in oil recovery
operation after low frequency
continuous operations
When Pd reaches When Pd is
27.5kg/cm
2
G
24kg/cm
2
G (341psi) or
(391psi) or more less 30 seconds
Item
When starting compressor
After thermost "ON is returned
and after 3 minutes restart
When compressor stops in
cooling or heating mode
After operation stops
During defrosting operations
(See figure below ✻1)
During oil recovery operations
During 20Hz operations, at fall
in low pressure saturation
temperature. (ET) (3 minutes or
more after starting)
When high pressure rises (Pd)
When high pressure rises (Pd)
during 20Hz operations
(3 minutes after starting)
When discharge temperature
rises
(3 minutes after starting)
✻ Ex. SV1
When low pressure
saturation temp.
(ET) is -15˚C (5°F) or
more
When Pd is 23kg/
cm2G (327psi) or less
after 30 seconds
When high pressure
(Pd) is 20kg/cm2G
(284psi) or less
When discharge
temp. is 115˚C
(239°F) or less
SV2
OFF (Close)
ON (Open)
When low pressure
saturation temp. (ET)
is -30˚C (-22°F) or less
When Pd reaches
26kg/cm2G (370psi)
or more
Turned on when high
pressure (Pd) ex-
ceeds pressure limit
When temp. exceeds
130˚C (266°F) and Pd reaches
15kg/cm
2
G (213psi) or more
Start Thermo.
OFF Thermo.
ON
(4-minute) (3-minute)
Stop
Bypass
solenoid
valve
(SV1)
Compressor
(2-minute) (4-minute)
Defrost-
ing time
(*1)
-
26
-