SYMPTOM

DIAGNOSIS

REMEDY

 

 

 

Both fan & compressor not running.

Fuse open or breaker tripped.

Inspect and repair.

 

 

 

 

Poor power plug connection.

Inspect.

 

 

 

 

Power failure.

Inspect.

 

 

 

 

Control circuit malfuction.

Replace parts.

Compressor does not run.

Compressor motor windings open.

Replace compressor.

 

 

 

 

Compressor locked.

Replace compressor.

 

 

 

 

Defective overload.

Replace part.

 

Defective capacitor.

Replace part.

 

 

 

 

Control circuit malfuction.

Replace part.

 

 

 

 

Voltage drop at start.

Check supply wiring.

 

 

 

 

Pressure unequal at start.

Restart in 10 minutes. Inspect Control Circuit.

 

 

 

Fan does not run.

Fan motor windings open.

Replace part.

 

 

 

 

Defective capacitor.

Replace part.

 

Control circuit malfunction.

Replace part.

 

 

 

 

Defective bearing.

Replace part.

 

 

 

 

Fan blade interference.

Inspect.

 

 

 

Unit operates but does not cool.

Refrigerant circuit oil leak.

Leak repair and replenish gas.

 

 

 

 

Small or no sound of refrigerant flow.

leak repair and replenish gas, or

 

Low system temperature / pressure.

defective compressor. Replace part.

 

 

 

 

Small or no sound of refrigerant flow.

System restriction; replace capillary tube

 

High rise in temperature / pressure of

and strainer.

 

condenser (frost forms on evaporator).

 

 

 

 

Poor cooling.

Incorrect thermostat setting.

Adjust.

 

Open door or window.

Correct.

 

 

 

 

Air inlet or outlet obstructed.

Correct.

 

 

 

 

Unit exposed to sun.

Draw curtains.

 

Additional heat sources or occupants.

Recalculate cooling load.

 

 

 

 

Poor installation location.

Consider relocation.

 

 

 

 

Incorrect cooling load calculation.

Recalculate cooling load, resize.

 

Dirty filter.

Clean filter.

 

 

 

Overcooling.

Incorrect cooling load calculation.

Adjust fan speed and thermostat setting.

 

 

 

 

 

Recalculate cooling load, resize.

 

 

 

High level of noise and vibration.

Compressor noise or vibration.

Check compressor mounting & isolation.

 

 

 

 

Tubing noise and vibration.

Redress tubing.

 

 

 

 

Fan motor noise or vibration.

Check fan motor mounting.

 

 

 

 

 

Check for broken fan blade.

 

 

 

Radio noise and interference.

Defective electrical contact.

Repair.

 

 

 

Water leaks.

Drain pipe blocked.

Inspect and repair.

 

 

 

 

Drain pipe blocked.

Inspect and repair.

 

Improper installation.

Inspect and repair.

 

 

 

D2

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Image 41
Fedders R407C service manual Symptom Diagnosis Remedy

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.