To Shut Off Unit - Carrier 48HC User's Information Manual

Fig. 6 - - Gas Component Access Panel Removal
Move the RTU gas valve on/off switch to the
Step 5 —
OFF position and wait 5 minutes. See Fig. 7.
Two-Stage
RTU gas valve
Fig. 7 - - Two- - Stage RTU Gas Valves
Move the RTU gas valve on/off switch to
Step 6 —
the ON position.
Replace the gas component access panel.
Step 7 —
Fig. 8 - - Replacing the Gas Component Access Panel
Remove disconnect lockout tag and restore
Step 8 —
power to the unit by switching the RTU main
disconnect to ON.
MAIN
Fig. 9 - - RTU Main Disconnect - - Electrical Supply
NOTE: Normal operation will automatically begin.
Service Test mode will automatically end (exit) after a
recycle of power.
Open the gas supply shut- -off valve located
Step 9 —
outside the unit.
Fig. 10 - - Gas Supply Shut Off Valve
300k BTU/Hr
Two-Stage
RTU gas valve
On/Off
Switch
OFF
ON
ON
Using the Scrolling Marquee, enable the
Step 10 —
unit to run using the following procedure:
a. Push the ESCAPE key until a blank display
screen is shown.
b. Push the DOWN arrow key until the SERVICE
TEST LED is lit.
c. Push the ENTER key. The display will show
C08487
TEST.
d. Push the ENTER key again. The NO/YES dis-
play will flash.
e. Push the UP or DOWN key to toggle the display
to NO and then push ENTER. The unit will re-
turn to normal operation and exit SERVICE
TEST mode.
To test the operation of the gas section, use
Step 11 —
the Scrolling Marquee test routine to energize the gas
outputs and to turn on the gas.
MODE
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Run Status
Service Test
Temperature
Pressures
Setpoints
Inputs
Outputs
Configuration
Time Clock
Operating Modes
Alarms
Fig. 11 - - ComfortLink Controller
For normal operation, make sure that the
Step 12 —
set points are at the normal heat set points.
!
C08490
FIRE, EXPLOSION HAZARD
Failure to follow this warning could result in personal
injury, death or property damage.
If the main burners fail to light, or the blower fails to
come on, shut down gas heating section and call your
dealer for service.

TO SHUT OFF UNIT

!
C07336
FIRE, EXPLOSION HAZARD
Failure to follow this warning could result in personal
injury, death and/or property damage.
1. Turn off gas supply by closing the gas line supply
valve. Then, turn off the electrical power supply to the
unit by switching the disconnect to off. Install lockout
tag before servicing or performing maintenance.
2. Do not turn off the electrical power to unit
without first turning off the gas supply.
Should overheating occur, or the gas supply fail to shut
off, shut off the gas valve in the unit (by moving on/off
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switch to off) before shutting off the electrical supply.
4
Alarm Status
ESCAPE ENTER
WARNING
WARNING
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