Fedders R407C service manual Modes of Operation, Cool Mode Cycle

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V.Modes of Operation

1.Cool Mode

The air-con controller lowers the room temperature in this mode.

In cool mode, the indoor fan is always turned on, allowing it to run at the set speed.

To stop the cool mode cycle, the compressor, outdoor fan are turned off, the 4-way valve which serves no function in this mode is still kept at off. The indoor fan is however allowed to continue running at set speed.

The controller monitors room temperature and compares it against set/desired temperature. It starts and stops the cool mode cycle according to the following rules:

Room Temperature

< Set pt-1°C

= Set pt-1°C

= Set pt.

= Set pt+1°C

> Set pt+1°C

Cool Mode Cycle

Stop

Stop

*

Start

Start

*Maintain current state

If room temperature ≤ 16°C, compressor, outdoor fan and 4-way valve turn off. The indoor fan runs according to following table:

ID Room Temp., Tr

Tr<=15°C

15°C<Tr<16°C

Tr>=16°C

ID Fan

LOW

*

SET

*Maintain current state

2.Dry Mode

Dry mode operation extracts moisture from the indoor air and tries to maintain room temperature to the default set temperature of 22°C.

To dry the air, the controller executes the dry mode cycle, which toggles the compressor and outdoor fan on for 10 minutes and off for 5 minutes repetitively.

The temperature setting, which is not changeable by user, is internally set at 22°C.

In this mode, the indoor fan constantly runs at the low speed. The 4-way valve that serves no function in this mode is always kept OFF.

Room Temperature

<Set pt-1°C

Set pt-1 °C

Set pt.

Set pt+1°C

>Set pt+1°C

Dry Mode Cycle

Start

Start

*

Pre-dry

Pre-dry

Pre-dry : compressor on, outdoor fan on and 4-way valve kept off.

*Maintain current state

3.Heat Mode (applicable on Heat Pump Unit only)

Heat mode operation can be chosen if it is desired to raise the room temperature. In this mode, the air-con controller turns on the compressor, outdoor fan, 4-way valve and indoor fan to provide the heating effect. The above operation, when executed in accordance to the device protection criteria and cool fan prevention requirement is termed the heat mode cycle.To stop heat mode cycle, the compressor and outdoor fan are turned off.

F7

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Contents Fedders Page Section a Specifications Container Loading Section B Parts List and Exploded Views Fedders Large Split AIR CONDITIONERR407C Service Parts List Model Number Fedders Refrigerant Assembly Packaging Parts Page Page Page R407C Refrigerant ASSEMBLYCont Packaging Parts Page Page Page Page Section C Installation Split Type AIR Conditioner Installation Manual Contents Safety Precaution Part Lists Pipe Length, Elevation and refrigerant charge Cutting The Pipe And The CablesRemoving burrs Flaring of pipeInstalling the wall bracket & drilling the piping hole Locating the indoor unitRemoving The Decorative Front Routing the drain hose and tubingDrain hose Use caution When bending Sealing The Drain Hose And TubingWiring The Indoor Unit Attaching The Unit To The Wall BracketConnecting The Piping To The Indoor Unit Outdoor Unit Installation Locating the outdoor unitInstalling The Outdoor Unit Connecting The Pipe To The Outdoor UnitConnecting The Wires To The Outdoor Unit Checking for gas leakage Removing air from the tubing and indoor unitRestraining the piping Switch On The Power Supply Test RUN & CheckUpon completion of installing and checking the unit Checking The UnitSection D Trouble Shooting Page Symptom Diagnosis Remedy Section E Wiring Diagram Page Page Page Page Section F Technical Data Large Split Unit 18 / 24K II. Hand-held Transmitter Applicable on Heat Pump UnitIII. Receiver Module Main Receiver BoardLED Board IV. Operations of the electronic controller LEDStep Cool Mode Cycle Modes of OperationHeat Mode Heat Pump Unit only VI. Temperature Control and Measurement VII. Auto Fan FunctionIndoor Fan Speed VIII. Vane Function Cool or auto-cool mode IX. Sleep FunctionTimer Function ON-OFF-ON OperationHeat mode protection applicable on Heat Pump Unit only XI. Device Protection MeasuresHeat Mode Cycle 10C Indoor coil Temperature 2C Compressor Fan Min 10 min Defrosting in Heat mode applicable on Heat Pump Unit only Defrost Time Chart XII. Thermistor fault indication Heat Overload Protection AlgorithmXIV. Memory Backup of Settings XIII. Self TestF21 F22 F23 F24 F25 F26 F27 F28

R407C specifications

Fedders R407C is a commonly used refrigerant that has made significant strides in the air conditioning and refrigeration industries. Developed as a replacement for R22, R407C blends three refrigerants: R32, R125, and R134a. This combination gives it versatile applications and makes it a popular choice in residential and commercial systems.

One of the main features of R407C is its zero ozone depletion potential (ODP). This is crucial in an era where environmental regulations are stricter and focus on reducing substances that could harm the ozone layer. R407C also boasts a relatively low global warming potential (GWP) compared to other refrigerants, which aligns with the growing demand for low-impact environmentally friendly solutions.

Technologically, R407C is compatible with many existing systems, particularly those designed for R22, making it a favored transitional refrigerant during the phase-out of ozone-depleting substances. However, it is vital to note that R407C operates at a higher pressure than R22, meaning that certain system components may need upgrading to ensure optimal performance and safety.

In terms of thermodynamic characteristics, R407C has a refrigerating effect similar to R22, making it efficient for cooling purposes across various applications. It has good heat transfer properties, which translates to efficient energy use in both residential and commercial installations. The refrigerant operates effectively across a broad temperature range, making it an ideal choice for air conditioners, heat pumps, and chillers.

Moreover, R407C is a near-azeotropic blend, which implies that it maintains its composition during evaporation and condensation. This characteristic helps in minimizing the risks of refrigerant fractionation, allowing for consistent performance over time.

Another noteworthy aspect of Fedders R407C is its favorable safety profile. It has a lower toxicity level compared to some other refrigerants, which enhances its suitability for varied applications. Additionally, it is non-flammable under normal conditions, making it a safe option for different installations.

In conclusion, Fedders R407C is characterized by its environmental safety, excellent thermodynamic qualities, and compatibility with existing refrigeration systems. As industries strive to meet new environmental regulations, R407C serves as a reliable option, providing performance without compromising on ecological concerns. Its pivotal role in transitioning to greener alternatives makes it a critical refrigerant in today’s climate-conscious market.
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