Combustion-Air Blower — Clean periodically to assure proper airflow and heating efficiency. Inspect blower wheel every fall and periodically during heating season. For the first heating season, inspect blower wheel bimonthly to deter- mine proper cleaning frequency.

To access burner section, slide the sliding burner partition out of the unit.

To inspect blower wheel, shine a flashlight into draft hood opening. If cleaning is required, remove motor and wheel as follows:

1.Slide burner access panel out.

2.Remove the 7 screws that attach induced-draft motor housing to vestibule plate (Fig. 50).

3.The blower wheel can be cleaned at this point. If addi- tional cleaning is required, continue with Steps 4 and 5.

4.To remove blower from the motor shaft, remove 2 setscrews.

5.To remove motor, remove the 4 screws that hold the mo- tor to mounting plate. Remove the motor cooling fan by removing one setscrew. Then remove nuts that hold mo- tor to mounting plate.

6.To reinstall, reverse the procedure outlined above.

Limit Switch — Remove blower access panel (Fig. 7). Limit switch is located on the fan deck.

Burner Ignition — Unit is equipped with a direct spark ignition 100% lockout system. Integrated Gas Unit Controller (IGC) is located in the control box (Fig. 11). The IGC contains a self-diagnostic LED (light-emitting diode). A single LED on the IGC provides a visual display of operational or sequential problems when the power supply is uninterrupted. When a break in power occurs, the IGC will be reset (resulting in a loss of fault history) and the indoor (evaporator) fan ON/OFF times will be reset. The LED error code can be observed through the viewport. During servicing refer to the label on the control box cover or Table 31 for an explanation of LED error code descriptions.

If lockout occurs, unit may be reset by interrupting power supply to unit for at least 5 seconds.

Table 31 — LED Error Code Description

LED INDICATION

ERROR CODE DESCRIPTION

ON

Normal Operation

OFF

Hardware Failure

1 Flash†

Evaporator Fan On/Off Delay Modified

2 Flashes

Limit Switch Fault

3 Flashes

Flame Sense Fault

4 Flashes

4 Consecutive Limit Switch Faults

5 Flashes

Ignition Lockout Fault

6 Flashes

Induced-Draft Motor Fault

7 Flashes

Rollout Switch Fault

8 Flashes

Internal Control Fault

LEGEND

 

LED — Light-Emitting Diode

*A 3-second pause exists between LED error code flashes. If more than one error code exists, all applicable codes will be displayed in numerical sequence.

†Indicates a code that is not an error. The unit will continue to oper- ate when this code is displayed.

IMPORTANT: Refer to Troubleshooting Tables 32-36 for addi- tional information.

Main Burners — To access burners, remove burner ac- cess panel and slide out burner partition. At the beginning of each heating season, inspect for deterioration or blockage due to corrosion or other causes. Observe the main burner flames and adjust, if necessary.

When working on gas train, do not hit or plug orifice spuds.

REMOVAL AND REPLACEMENT OF GAS TRAIN (Fig. 50-52)

1.Shut off manual gas valve.

2.Shut off power to unit.

3.Slide out burner partition.

4.Disconnect gas piping at unit gas valve.

5.Remove wires connected to gas valve. Mark each wire.

6.Remove ignitor wires and sensor wires at the Integrated Gas Unit Controller (IGC) (see Fig. 11).

7.Remove the 2 screws that attach the burner rack to the vestibule plate (Fig. 50).

8.Slide the burner tray out of the unit (Fig. 51).

9.To reinstall, reverse the procedure outlined above.

CLEANING AND ADJUSTMENT

1.Remove burner rack from unit as described in Removal and Replacement of Gas Train section, above.

2.Inspect burners; if dirty, remove burners from rack.

3.Using a soft brush clean burners and cross-over port as required.

4.Adjust spark gap. See Fig. 52.

5.Reinstall burners on rack.

6.Reinstall burner rack as described in Removal and Re- placement of Gas Train section, above.

Replacement Parts — A complete list of replacement parts may be obtained from any Carrier distributor upon request.

INDUCED-

ROLLOUT

DRAFT

SWITCH

MOTOR

 

MOUNTING

 

PLATE

 

BURNER

 

SECTION

FLUE

 

EXHAUST

 

VESTIBULE

INDUCED-

PLATE

DRAFT

BLOWER

MOTOR

 

HOUSING

MANIFOLD

GAS

PRESSURE

TAP

VALVE

Fig. 50 — Burner Section Details

42

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Carrier 48TF004-007 specifications LED Error Code Description, LED Indication Error Code Description, Off, Flashes
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48TF004-007 specifications

The Carrier 48TF004-007 is part of the brand's renowned rooftop unit series, designed to deliver efficient, reliable performance for commercial applications. Ideal for spaces such as offices, retail stores, and small manufacturing facilities, these units encapsulate advanced technology to enhance indoor air quality and optimize climate control.

One of the standout features of the Carrier 48TF004-007 units is their variable speed compressor technology. This innovation not only allows for precise temperature control but also reduces energy consumption by modulating the compressor's speed according to the cooling or heating demand. By operating at lower speeds during less demanding conditions, these units significantly decrease energy usage compared to traditional single-speed compressors, contributing to lower utility bills and a reduced carbon footprint.

Energy efficiency is further enhanced with the inclusion of high-performance scroll compressors, which are known for their reliable operation and quiet performance. Coupled with an Energy Efficiency Ratio (EER) that meets or exceeds industry standards, these systems are designed to offer economical operation without sacrificing comfort.

Incorporating smart controls and connectivity features, the Carrier 48TF004-007 units allow for easy integration into building management systems (BMS). This enhances the ability to monitor and manage energy usage in real time, further promoting efficiency. The units are also compatible with various thermostat options, allowing for user-friendly operation and customization of settings.

Another significant characteristic of the Carrier 48TF004-007 is its durable construction. Built with galvanized steel and powder-coated finishes, these units are designed to withstand the rigors of outdoor installation, ensuring long-lasting performance even in harsh weather conditions. Additionally, the units come equipped with advanced filtration systems that help improve indoor air quality by effectively removing dust, allergens, and other particulate matter from the air.

Maintenance is simplified with the Carrier 48TF004-007, providing easy access to vital components, which supports reduced downtime and service costs. The units also feature low operating sound levels, making them suitable for noise-sensitive applications.

In conclusion, the Carrier 48TF004-007 rooftop units stand out for their energy efficiency, advanced technology, durability, and ease of maintenance, making them an excellent choice for any commercial space looking to enhance comfort while effectively managing operational costs.
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