Carrier 40MBFAQ Service Manual page 7

40MBFAQ: Service Manual
Main Protection
Fan Speed is Out of Control
When the indoor fan speed remains too low (lower than 300RPM) for 50
seconds, the indoor fan will shut off then restarts 30 seconds later. If
protection occurs three times when the fan motor restarts continuously,
the unit stops and the LED displays the failure.
When the outdoor fan speed remains too low (lower than 100 RPM) or
too high (higher than 1500 RPM) for 60 seconds, the unit stops and the
LED displays the failure. The malfunction is cleared 30 seconds later.
Evaporator low temperature T2 protection
• T2 < 32 ° F (0 ° C), the compressor stops and restarts when T2
(5 ° C).
C) ≤ T2 < 39.2
• 32 ° F (0 ° ° F (4
and decreased to the lower level.
C) ≤ T2 ≤ 44.6
• 39.2 ° F (4 ° ° F (7
current frequency
• T2 > 44.6 F (7 C), the compressor frequency is not limited.
° °
Operation Modes and Functions
FAN Mode
1. Outdoor fan and compressor stop
2. Temperature setting function is disabled, and no setting temperature
appears
3. Indoor fan can be set to high/med/low/auto
4. The louver operates the same in the COOLING mode
5. AUTO fan
T1-75.2°F (24°C)
..........................................................................
12°F (6°C)
a
10°F (5°C)
b
8°F (4°C)
c
5°F (2.5°C)
d
2°F (1°C)
Fig. 9 —Auto Fan
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
° C), the compressor frequency is limited
° C), the compressor maintains the
H
(H-L)*0.75+L
........................
(H-L)*0.5+L
........................
(H-L)*0.25+L
........................
L
e
COOLING Mode
Indoor Fan Running Rules
In the COOLING mode, the indoor fan runs constantly and either speed
(high, medium, low or auto) can be selected. When the setting temperature
is reached, if the compressor stops running, the indoor fan motor runs at the
minimum or setting speed. The indoor fan is controlled by the rules shown in
Fig. 10.
Setting Fan
T1-Td °F (°C)
Speed
³
41
° F
H
M
L
Fig. 10 — Indoor Fan Running Rules
A220982
7
Actual Fan Speed
A220983