Fedders R407C service manual Step

Models: R407C

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3.3-min. compressor switch on delay

The compressor is not switched on again immediately after being switched off. The air-con controller waits for 3 minutes before turning it on again to protect it.

This protective measure applies throughout the operation of the air-con except on power-up.

4.60-second4-way valve delay (applicable on Heat Pump Unit only) This refers to the 60-second delay after turning off

compressor before the 4-way valve is switched over from off to on or vice-versa.

This delay allows the safe, gradual transition of the air-con operation from a cooling function to heating function or vice versa.

5.Cool fan prevention in heat mode (applicable on Heat Pump Unit only)

When compressor starts in heating operation or after defrosting, the indoor fan changes the speed due to the indoor coil thermistor temperature and operation time to blow out warm air.The indoor fan runs according to the following table during heat mode:

STEP 1:

 

ID Coil Temp., T

T<=28°C

28°C<T<30°C

T>=30°C

 

ID Fan

STOP

*

LOW

STEP 2:

 

 

 

 

ID Coil Temp., T

T<=33°C

33°C<T<36°C

T>=36°C

 

ID Fan

LOW

*

SET

STEP 3:

 

 

 

 

ID Coil Temp., T

T<=46°C

46°C<T<50°C

T>=50°C

 

ID Fan

SET

*

HIGH

* Maintain current state

The start-up warm airflow control program is regardless room temperature. The indoor fan is also not switched on while the outdoor coil is being de-iced for the same reason.

6.Indoor coil icing prevention in cool mode

Should the indoor coil temperature dip to 2°C or lower in cool mode for at least 2 mins, de-icing will be executed to remove the ice formed at the indoor coil. De-icing will be stopped when the indoor coil temperature rises to 10°C or higher or 10 mins lapse.

7.Outdoor coil icing prevention in heat mode (applicable on Heat Pump Unit only)

If the outdoor coil temperature dips to below -4°C in heat mode. It will perform De- ice according to a specified algorithm, and de-ice the outdoor coil if necessary.

F6

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Fedders R407C service manual Step

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.