Carrier 50GCQ Series Service And Maintenance Instructions page 55

Cooling
Set space thermostat to OFF position. To start unit, turn on
main power supply. Set system selector switch at COOL posi-
tion and fan switch at AUTO position. Adjust thermostat to a
setting below room temperature. Compressor starts on closure
of contactor.
Check unit charge. Refer to Refrigerant Charge section on
page 15.
Reset thermostat at a position above room temperature. Com-
pressor will shut off. Evaporator fan will shut off after a
30-second delay.
To shut off unit, set system selector switch at OFF position.
Resetting thermostat at a position above room temperature
shuts unit off temporarily until space temperature exceeds ther-
mostat setting.
Heating
To start unit, turn on main power supply. Set system selector
switch to the HEAT position and set thermostat at a setting
above room temperature. Set fan to AUTO position.
First stage of thermostat energizes the first stage of the electric
heaters. Second stage of thermostat energizes the second stage
of electric heaters (if installed). Check heating effects at air
supply grille(s).
If electric heaters do not energize, reset limit switch (located on
supply-fan scroll) by pressing button located between termi-
nals on the switch.
To shut unit off, set system selector switch to the OFF position.
Resetting thermostat at a position below room temperature
temporarily shuts unit off until space temperature falls below
thermostat setting.
Ventilation (Continuous Fan)
Set fan and system selector switches at ON and OFF positions,
respectively. Evaporator fan operates continuously to provide
constant air circulation.
FASTENER TORQUE VALUES
Heat shield screws
Stator motor mounting
screws
Fan rotor mounting
screws
Limit switch screws
Fan Deck bracket screws 50 in.-lb (5.7 Nm) ±5 in.-lb (0.6 Nm)
Condenser fan motor
mounting screws
Condenser fan hub set
screw
Compressor mounting
bolts
START-UP, RTU OPEN CONTROLS
IMPORTANT: SET-UP INSTRUCTIONS
For installation, wiring, and troubleshooting information for
the RTU Open Controller, see "RTU Open Multi-Protocol
Controller Factory-Installed Option — Controls, Start-up, Op-
eration and Troubleshooting Instructions." Have a copy of this
manual available at unit start-up.
START-UP, SYSTEMVU CONTROLS
IMPORTANT: SET-UP INSTRUCTIONS
For installation, wiring, and troubleshooting information for
the SystemVu™ Controller, see "50FCQ 04-07, 50GCQ 04-
06 Single Package Rooftop Units with SystemVu Controls
Version X.X Controls, Start-up, Operation and Troubleshoot-
ing." Have a copy of this manual available at unit start-up.
55
30 in.-lb (3.4 Nm) ±2 in.-lb (0.2 Nm)
23 in.-lb (2.6 Nm) ±2 in.-lb (0.2 Nm)
23 in.-lb (2.6 Nm) ±2 in.-lb (0.2 Nm)
50 in.-lb (5.7 Nm) ±5 in.-lb (0.6 Nm)
30 in.-lb (3.4 Nm) ±3 in.-lb (0.3 Nm)
60 in.-lb (6.8 Nm) ±5 in.-lb (0.6 Nm)
65 in.-lb (7.3 Nm) +10 in.-lb (1.2 Nm)