To Light Unit, Typical Gas Heating Section

Step 10 — Set room thermostat selector slightly above room temperature and set system switch to HEAT position to start the unit. The induced-draft combustion air fan will start. Main burners light within 30 seconds. Indoor blower will start within 60 to 90 seconds of main gas ignition.

Step 11 — Set the temperature selector on room thermostat to desired setting.

INDUCED

DRAFT

MOTOR

COMBUSTION

FAN HOUSING

MAIN GAS

VALVE

HEAT EXCHANGER	MAIN BURNER SECTION
SECTION

C06258

Fig. 1 - Typical Gas Heating Section

!WARNING

FIRE, EXPLOSION HAZARD

Failure to follow this warning could result in personal injury, death, and/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 LIGHT UNIT

(UNITS WITH COMFORTLINKt

CONTROL)

!DANGER

FIRE, EXPLOSION HAZARD

Failure to follow this warning could result in personal injury, death, and/or property damage.

1.Do not turn off the electrical power to unit without first turning off the gas supply and applying lockout tags.

2.Before attempting to start the gas heating section, familiarize yourself with all the procedures that must be followed.

3.Never attempt to manually light the burners on the unit with a match, lighter, or any other flame. If the electric sparking device fails to light the burners, refer to the shutdown procedures, then call your dealer as soon as possible.

See Fig. 1. for location of gas valve. Refer to Fig. 3 while proceeding with the following steps:

Step 1 — Turn off the unit by using the Scrolling Marquee to put the unit into Service Test mode. The Scrolling Marquee is located on the front of the unit control box behind the control box and compressor access door. Thermostat inputs and remote network commands are ignored when Service Test mode is ON.

NOTE: A password may be required to change Service Test values, depending on previous settings configured in the unit. Default password is “1111.”

a.Press the ESCAPE key until a blank screen is shown.

b.Use the arrow keys to scroll the red LED on the display to the “Service Test” position and press ENTER.

c.The control will display the Field Service Test Mode (TEST) setting. Press ENTER once to select the TEST setting for configuration. Press ENTER again for “OFF” to begin flashing.

d.Use the arrow keys to change the configuration from “OFF” to “ON,” then press ENTER to save the setting.

Step 2 — Close the shutoff valve on the gas supply piping. Step 3 — Turn off the electrical supply to the unit and install lockout tag.

Step 4 — Open the heat section access panel.

Step 5 — Move ON/OFF switch on the internal gas valve to the OFF position and wait 5 minutes.

Step 6 — Move ON/OFF switch on internal gas valve to ON position.

Step 7 — Close the heat section access panel.

Step 8 — Remove lockout tag and turn on the electrical supply to unit.

NOTE: Normal operation will automatically begin. Service Test mode will automatically end (exit) after a recycle of power.

Step 9 — Open the shutoff valve on the external gas supply piping.

Step 10 — To test the operation of the gas section, the HEAT submenu of Service Test may be used. See the Controls, Start-Up, Operation, Service, and Troubleshooting Instructions for more details on use of Service Test.

Step 11 — For normal operation, make sure that the set points are at the normal heat set points.

!WARNING

FIRE, EXPLOSION HAZARD

Failure to follow this warning could result in personal injury, death, and/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.

48PD, 48PG

48PD05, 06 specifications

The Carrier 48PD05 and 48PD06 are highly efficient packaged rooftop units designed specifically for commercial applications. They are known for their reliability, advanced technologies, and exceptional performance in diverse weather conditions. Both units leverage Carrier's decades of experience in HVAC technology to deliver optimal indoor comfort with minimal energy consumption.

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Energy efficiency is a key characteristic of the 48PD05 and 48PD06. Both units feature high SEER (Seasonal Energy Efficiency Ratio) ratings, ensuring that they consume less electricity while delivering superior cooling performance. The use of microchannel coil technology further enhances efficiency. This innovation reduces refrigerant charge requirements and improves heat transfer, allowing the units to operate effectively in various climatic conditions.

In addition to cooling, these units also provide heating functionality, making them an all-in-one solution for year-round climate control. They incorporate electric heating elements as well as optional gas heat capabilities, providing flexibility based on user preference and fuel availability. This versatility ensures that facilities can maintain comfort regardless of seasonal changes.

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Safety and reliability are paramount in Carrier's design philosophy. Both units include a variety of safety features such as high-pressure and low-pressure switches, ensuring the longevity and protection of the system. Additionally, the intelligent controls available with the 48PD models facilitate precise temperature management, enhancing occupant comfort while optimizing energy use.

In conclusion, the Carrier 48PD05 and 48PD06 packaged rooftop units stand out due to their efficient cooling and heating capabilities, innovative technologies, and user-friendly design. Their combination of performance, energy efficiency, and advanced features makes them a reliable choice for commercial heating and cooling needs, assuring users of comfort and cost-effectiveness throughout their operation.