Operation Modes And Functions; Abbreviation; Safety Features; Display Function - Carrier 42QHP09E8S Service Manual

1. Operation Modes and Functions

1.1

Abbreviation

Unit element abbreviations
Abbreviation Element
T1 Indoor room temperature
T2 Coil temperature of evaporator
T3 Coil temperature of condenser
T4 Outdoor ambient temperature
Tsc Adjusted setting temperature
TP Compressor discharge temperature
1.2

Safety Features

Compressor three-minute delay at restart
Compressor functions are delayed for up to ten seconds
upon the first startup of the unit, and are delayed for up
to three minutes upon subsequent unit restarts.
Automatic shutoff based on discharge temperature
If the compressor discharge temperature exceeds 108°C
for nine seconds, the compressor ceases operation.
Automatic shutoff based on fan speed
If the indoor fan speed registers below 300RPM or over
1500RPM for an extended period of time, the unit ceases
operation and the corresponding error code is displayed on
the indoor unit.
Inverter module protection
The inverter module has an automatic shutoff mechanism
based on the unit's current, voltage, and temperature.
If automatic shutoff is initiated, the corresponding error
code is displayed on the indoor unit and the unit ceases
operation.
Indoor fan delayed operation
• When the unit starts, the louver is automatically
activated and the indoor fan will operate after a period
of setting time or the louver is in place.
• If the unit is in heating mode, the indoor fan is
regulated by the anti-cold wind function.
Compressor preheating
Preheating is automatically activated when T4 sensor is
lower than setting temperature.
Sensor redundancy and automatic shutoff
• If one temperature sensor malfunctions, the air
conditioner continues operation and displays the
corresponding error code, allowing for emergency use.
• When more than one temperature sensor is
malfunctioning, the air conditioner ceases operation.
1.3

Display Function

Unit display functions
Function
Temperature
Temperature
(fan and Drying mode)
Activation of Timer ON,
Fresh, Swing, Turbo, or
Silent
Cancellation of Timer
OFF, Fresh, Swing,
Turbo, or Silent
Defrost
Warming in heating
mode
Self-clean (available on
select units only)
Heating in room
temperature
under 8°C or 12°C
Fresh(available on select
units only)
ECO function (available
on select units only)
WiFi control (available
on select units only)
The current operation
power(available on
select units only)
Display
Set temperature value
Room temperature
(3s)
(3s)
kW
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