Carrier 50FC User Manual (English)

Other manuals for Carrier 50FC

Questions and Answers:

J
Jaclyn ScottAug 5, 2025
What to do if my Carrier 50FC LCD has strange characters or a blank display?
- P
  Peter MackAug 6, 2025
  If your Carrier Air Conditioner's LCD shows strange characters or a blank display when switching on, check the following: 1. That the software in the flash is correct. 2. The addresses of the ?PC3 control board and the Graphic terminal (check that they comply with the requirements of the current application). 3. The connection between the Graphic terminal and the ?PC3 board.
W
woodwardkarenAug 16, 2025
What to do if there is an unusual alarm signal from the digital input of my Carrier Air Conditioner?
- R
  Rhonda RichardsonAug 16, 2025
  To troubleshoot unusual alarm signals from the digital input of your Carrier Air Conditioner, check if the alarm signal is present at the input. Measure the voltage between the 'IDC' common terminal and the digital input terminal which indicates the alarm 'IDn'. If voltage is present (24 Vac or Vdc, depending on the power supply used for the digital inputs), the contact of the connected alarm device is closed. If the voltage is near 10 Vac or 10 Vdc, the contact is open.
C
Christopher SmithAug 25, 2025
How to troubleshoot erroneous readings of the input signals on a Carrier Air Conditioner?
- T
  Tina CarrollAug 26, 2025
  To troubleshoot erroneous readings of the input signals in your Carrier Air Conditioner, check the following: 1. The correct power supply to the control board and probes. 2. The separation between the power supply of the digital inputs and that of the control board. 3. That the cables from the probes are connected according to the instructions. 4. That the probe cables are located far enough away from possible sources of magnetic interference (power cables, contactors, high voltage cables or cables connected to units with high current peaks). 5. That there is not a high level of heat resistance between the probe and the sensor cap (if present). If necessary, apply conductive paste or oil into the caps to ensure good temperature transfer.

Carrier 50FC Specifications

General

Brand	Carrier
Model	50FC
Category	Air Conditioner
Language	English

Summary

Introduction to Carrier Rooftop Units

General Safety Advice for Unit Operation

Essential safety guidelines for installation, operation, and maintenance, including PPE and precautions.

Safety Standards for Refrigerant Handling

Safety Standards for Refrigerant Types

Details safety standards for refrigerants R-410A and R-454B, including handling and leak detection.

Unit Assembly Configurations

Unit Transportation Guidelines

Transport Safety and Regulations

Covers transport safety, directives, and general precautions for handling units.

Receipt of Goods Inspection

Procedures for checking the unit upon receipt to ensure no damage or missing parts.

Unit Identification Markings

Information on markings like name plates that must remain visible.

Unit Handling Procedures

Forklift Handling Instructions

Instructions for safely handling the unit using a forklift, including fork placement and weight distribution.

Crane Lifting Procedures

Guidelines for lifting the unit with a crane, emphasizing rigging points and slings.

Unit Weight and Dimensions for Handling

Detailed specifications for various unit models, crucial for safe handling and transport.

Rigging Configurations for Lifting

Diagrams illustrating rigging points for specific unit configurations during lifting.

Correct Unit Lifting Mode

Illustrates the proper method for lifting the unit using a crane, emphasizing safe sling attachment.

Operation Limits and Installation

Unit Operation Limits

Specifies the operating temperature limits for cooling and heating modes, including indoor and outdoor coil conditions.

Positioning and Installation Overview

General guidelines for installing the unit, covering storage, location choice, and ATEX zones.

Storage Recommendations

Recommendations for storing the unit to prevent damage and maintain optimal conditions.

Choice of Installation Location

Criteria for selecting a suitable installation site, considering regulations, altitude, structure, and access.

Unit Sound Level Information

Information on the unit's acoustic performance, including sound power and pressure levels, and vibration reduction.

Antivibrator Assembly (Silent-blocks)

Instructions for installing antivibration mounts (silent-blocks) to reduce noise and vibration transmission.

Pre-assembly Roofcurb Installation

Details on installing optional pre-assembly roofcurbs, including adjustable height and leveling features.

Roofcurb Handling and Installation

Specific instructions for handling the roofcurb, including lifting grips and safety checks.

Roofcurb Installation on the Roof

Steps for installing the roofcurb on the building structure, including adjusting angle pieces and ensuring proper alignment.

Roofcurb Orientation and Sealing

Guidelines for proper insulation and sealing of the roofcurb to prevent water ingress and thermal loss.

Roofcurb Dimensions and Duct Connections

Instructions for connecting air ducts to the roofcurb, referring to specific sections for details.

Unit Positioning on Roofcurb

Steps for placing the main unit onto the installed roofcurb, ensuring proper fit and sealing.

Unit Weight and Support Reactions

Detailed tables of center of gravity, weight, and support reactions for various unit assemblies and models.

Service Clearance Requirements

Minimum required clearances around the unit for maintenance, access, and proper air circulation.

Service Clearance for Larger Units

Service clearance requirements for larger unit models (180-280), detailing dimensions for access and maintenance.

Electrical Connection Procedures

Electrical Installation Norms

Essential rules for site electrical installations, safety precautions, and grounding.

Power Supply Verification

Guidance on verifying power supply compatibility, phase imbalance, and protection measures.

Wire Sizing Guidelines

Information on responsible wire sizing based on unit specifications and applicable regulations.

Electrical Cabinet Overview

Description of the unit's electrical cabinet, including its features and access for wiring.

Internal Electrical Box Locations

Diagrams showing the location of internal electrical boxes for different unit models.

50FC Electronic Control System

Overview of the '50FC' electronic control system, including its components and connection options.

Sensor Locations on the Machine

Diagrams showing the placement of various sensors (temperature, pressure, etc.) on the unit's circuits.

Customer Sensor Connections

Instructions for customers on connecting external probes like ambient, air quality, and outdoor humidity sensors.

Outdoor Humidity Probe Installation

Detailed steps for installing and connecting the optional outdoor humidity probe.

CO2 Air Quality Probe Connection

Information on connecting CO2 air quality probes, including installation and electrical connection details.

Fan and Air Duct Checks

Axial Fan Checks

Steps for inspecting axial fans before and during operation, checking rotation, pressure, and flow.

EC Plug-Fan Checks

Guidelines for checking EC plug-fans, including rotation, operation conditions, and flow control switches.

Centrifugal Fan Pulley and Belt Calibration

Instructions for calibrating pulleys and belts on centrifugal fans, emphasizing alignment and tension.

Centrifugal Fan Belt Tension Adjustment

Methods for checking and adjusting belt tension in fans, including deflection tests and calculation.

Air Duct Connection Recommendations

Recommendations for calculating and designing air supply and return ducts, including advice on bends and air recirculation.

Condensate Drain System

Siphon Installation Norms

Specific guidelines for installing a siphon in the condensate drain to prevent odors and water spills.

Unit Safety Elements

High Pressure Switch and Safety Valve

Explanation of the high-pressure switch function, activation setpoints, and safety valve specifications.

Low Pressure Safety Control

Description of the low-pressure safety mechanism managed by the electronic control.

Control Circuit Protection Devices

Information on the magnetothermal switch protecting the control circuit from surges.

Main Door Switch Function

Description of the main door switch preventing access to the electrical cabinet while the unit is energized.

Defrost Control System

Explanation of the defrost safety device that prevents ice accumulation in the outdoor coil during heating.

Compressor Safety Features

Details on klixon switches for compressor discharge protection against excessive heating.

Condensation and Evaporation Control

How the control manages outdoor fans for condensation and evaporation control in different modes.

Refrigerant Leak Detection Systems

Procedures and devices for detecting refrigerant leaks, including R-454B detectors and R-410A detectors.

Anti-Fire Safety Device

Details on the anti-fire safety device that stops the unit based on return air temperature.

Optional Smoke Detector Installation

Information on optional smoke detecting stations and their integration with unit operation.

Low Temperature Anti-Freeze Protection

Optional safety features like electrical heaters and crankcase heaters for low-temperature protection.

Factory Options and Accessories

Damper Hood Installation

Instructions for assembling and installing damper hoods for fresh air and exhaust air.

Droplet Eliminator Installation

Steps for installing a droplet eliminator on the fresh air intake, recommended for high moisture content.

Heat Recovery Wheel Module Handling

Details on transporting and handling the heat recovery wheel module, including installation and electrical connections.

Recovery Module Access and Filters

How to access the internal components of the heat recovery module, including filters.

Air Filter Types and Replacement

Information on available air filter types, their replacement, and handling.

Heat Recovery Coil Installation

Details on the heat recovery coil option, its function, installation, and connection.

Stop-Drop in Indoor Coil Option

Information about the stop-drop option for the indoor coil and its installation access.

Auxiliary Electrical Heaters

Description of auxiliary electrical heaters, their power stages, and management by the unit's control.

Hot Water Coil Installation

Details on the hot water coil option, its activation, antifreeze protection, and coil filling.

Warm Air Heater with Gas Burner

Information on the gas burner module, its performance, safety features, and installation requirements.

Gas Burner Fuel and Safety Checks

Important checks regarding fuel compatibility, supply, and safety for the gas burner.

Gas Leak Safety Procedures

Safety procedures to follow in case of gas leaks, including immediate actions and emergency contacts.

Gas Burner Operation Guidelines

General operating instructions for the gas burner, emphasizing safety and proper usage.

Gas Burner Identification

Information on the burner's name plate and serial number for identification.

Burner Condensate Drain Connection

How to connect the burner's condensate drain pan, with precautions for outdoor installations.

Outlet Temperature Probe Connection

Instructions for connecting the outlet temperature probe to the unit.

Burner Electrical Connection

Steps for connecting the burner control to the 50FC unit's electrical cabinet.

Flue Connections for Gas Burner

Requirements for flue connections, including materials, sealing, and installation incline.

Gas Flue Selection Guide

Guidance on selecting flue components based on routing, diameter, and pressure drop calculations.

Gas Connection Requirements

Details on gas line connections, required components, and safety regulations for different gas types.

Gas Category Country Table

Table categorizing countries by gas type and pressure requirements for the burner.

Gas Burner Type Conversion

Instructions for converting the gas burner from natural gas to LPG, including necessary parts and procedures.

Combustion Analysis Procedure

Procedure for analyzing combustion, checking CO2 levels, and adjusting burner settings.

Burner Operating Cycle

Description of the burner's operating cycle, including ignition, modulation, and shutdown phases.

Burner Fault Codes (Fxx)

Information on fault codes (Fxx) related to the burner's modulation PCB and how to reset them.

Air/Gas Premixing Operation

Explanation of the air/gas premixing process, including adjustment screws and fan rotation control.

50FC Control of Gas Burner

How the 50FC control manages the gas burner, including proportional output and operating modes.

Low Temperature Burner Protection

Details on the optional kit for low-temperature protection of the burner, including a heater and NTC probe.

Burner Interface Panel

Description of the burner's interface panel, used for control, configuration, and diagnostics.

Burner First Level Menu Navigation

Overview of the burner's first-level menu options (machine status, FUN, REG, TIN, PRA, ABI).

Burner Fault Reset Procedures

Instructions on how to reset the modulation PCB and manage fault codes.

Burner Fault Analysis and Remedies

A detailed table listing fault descriptions, causes, and remedies for burner-related issues.

Cooling Recovery Circuit (BA/BB Assemblies)

Description of the cooling recovery circuit, its components, and characteristics.

Air Flow Zoning Option

Explanation of the air zoning option, allowing control of airflow to multiple zones.

Air Zoning Box Connections

Details on connecting the air zoning control board, zone terminals, and servomotors.

Unit Commissioning Procedures

Pre-Commissioning Checks

Essential pre-commissioning checks, including power supply, electrical installation, sensor connections, and crankcase heater pre-heating.

Refrigerant Charge Control

How to check and adjust the refrigerant charge, including procedures for leaks and proper filling.

Commissioning Problems and Solutions

Common operational problems that may occur during commissioning and their potential causes.

Operational Checks and Data Recording

Guidelines for verifying unit operation and safety devices, including recommended data recording.

Unit Maintenance Procedures

General Maintenance Recommendations

Advice on maintenance contracts, professional servicing, and basic user checks.

Level 2 Maintenance Tasks

Specific tasks for Level 2 maintenance, focusing on electrical and mechanical systems, including annual checks.

Level 3 Maintenance Tasks

Advanced maintenance tasks requiring specialized skills, including component replacement and refrigerant circuit operations.

Accessing Main Unit Components

How to safely access major components like the compressor, considering refrigerant handling and safety precautions.

Filter Drier Maintenance

Function of the filter drier, how to check its condition, and when to replace it.

Refrigerant Checks and Safety

Information on refrigerants used (R-410A, R-454B), leak detection, and periodic tightness checks.

R-454B Leak Detector Operation

Details on the standard R-454B refrigerant leak detector, its installation, and operation.

R-410A Leak Detector (Optional)

Information on the optional leak detector for R-410A refrigerant and its maintenance.

Active Recovery Circuit Maintenance

Description of the optional cooling recovery circuit and its maintenance requirements.

Condensate Drainage Pan Cleaning

How to clean and maintain the condensate drainage pan and check for blockages.

Air Coil Cleaning Procedure

Instructions for cleaning the air coil to ensure efficient heat exchange.

Protective Grille Cleaning

How to remove and reinstall protective grilles for cleaning outdoor coils.

Electrical Cabinet Air Filter Cleaning

Checking and cleaning air filters within the electrical cabinet for proper ventilation.

Air Filter Maintenance

Procedures for cleaning and replacing air filters, including different types and access methods.

Recovery Module Air Filter Maintenance

Maintenance of air filters within the heat recovery module.

Centrifugal Fan Maintenance

Checking the condition of centrifugal fans and motors, including spare belts.

Gas Burner Maintenance

General maintenance and inspection procedures for the gas burner, emphasizing safety and compliance.

Burner Electrode Inspection

Detailed steps for inspecting and cleaning the burner's ignition and detection electrodes.

Flame Monitoring Equipment Inspection

Procedure for inspecting the flame monitoring system and verifying its operation.

Safety Thermostat Inspection

How to inspect and test the safety thermostat(s) on the heater module.

Ionization Current Inspection

Checking the ionization current value via the LCD display to ensure proper flame detection.

Breakdown Analysis and Control

High Evaporation Pressure Troubleshooting

Troubleshooting steps for high evaporation pressure related to air inlet conditions.

Low Condensation Pressure Troubleshooting

Troubleshooting for very low condensation pressure, often related to refrigerant leaks or airflow issues.

High Condensation Pressure Troubleshooting

Diagnosing high condensation pressure with respect to air outlet, possibly due to dirty condenser or fan issues.

Low Evaporation Pressure Troubleshooting

Troubleshooting steps when evaporation pressure is too low, triggering the safety cut-off.

Compressor Start-Up Issues (No Noise)

Diagnosing why the compressor is not starting or making noise, checking power and control elements.

Compressor Start-Up Issues (Intermittent)

Troubleshooting intermittent compressor motor sounds and start-up issues.

Repeated Compressor Cycling

Analyzing reasons for frequent compressor cycling, such as pressure issues or dirty evaporators.

Compressor Noise Diagnosis

Identifying causes of compressor noise, like loose attachments or oil lack.

Noisy Operation Troubleshooting

Addressing noisy operation due to improper installation or lack of antivibration protection.

Cycle Reversing Issues

Troubleshooting issues with the cycle reversing valve and defrosting system.

Humidity Probe Alarm Resolution

Steps to resolve alarms or errors related to the humidity probe.

Final Shutdown and Disposal

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