Toshiba MM-A0280HT Service Manual page 43

Item
6. Air volume
control
7. Freeze
prevention
control (Low
temp. release)
11
8. Cooling
refrigerant/
Heating oil
recovery
control
9. Short
intermittent
operation
compensation
control
10. Drain pump
control
Outline of Control
Indoor Units
Operation explanation and applied data, etc.
(1) By the command from the remote controller or the
central controller, "HIGH", "MED.", "LOW", or
"AUTO" operation is permissible.
(2) While air volume is in AUTO mode, the air volume
is changed according to the difference between Ta
and Ts.
COOL
+2
HIGH
+1
MED.
Ts
LOW
(1) In cooling operation, the air conditioner operates as
described below based upon temp. detected by TC1
and TC2 sensors.
• When "J" zone is detected for 2 minutes, the
command frequency becomes "S0" to the
outdoor unit.
• In "K" zone, the timer count is interrupted,
and held.
• When "I" zone is detected, the timer is cleared
and the operation returns to normal operation.
• When the command frequency becomes S0 with
continuation of "J" zone, operation of the
indoor fan in LOW mode occurs until it reaches
the "I" zone.
It is reset when the following conditions are
satisfied.
1) TC1≥10°C and TC2 ≥10°C
2) 30 minutes after the air conditioner has stopped.
I a
P
(°C)
K
Q
J
When the indoor units stand by, thermostat is OFF, or
unit operates with "FAN" mode, PMV of the indoor unit
is opened by a certain degree when the cooling
oil/heating refrigerant recovery signal is received from
the outdoor unit.
(1) For 5 minutes after the operation has started, the
operation is continued even if entering thermostat-
OFF condition.
(2) However, if the thermostat has been turned off by
changing the setup temp., the thermostat is OFF
with even the above condition. The protective
control has priority.
(1) During "COOL" operation, the drain pump
operates.
(2) When the float SW operates, the compressor stops
and the drain pump operates.
(3) When the operation of the float SW continues for
2 minutes, a check code is generated.
HEAT
Ultra low
+1 compressor
off
LOW
Ts
MED.
- 1
-2 HIGH
TC1 TC2
P 5 -12
Q -4 -15
44
Remarks
• During stop
operation, control to
prevent cold draft is
determined by TC2.
• Only for 4-way/2-way
ceiling cassette type,
operate the indoor
fan intermittently
during the recovery
operation.
• When CHECK code
"0b" occurs, the
outdoor units stop
and "STANDBY" is
displayed on the
remote controllers of
all the indoor units.