When the indoor fan control is set to Auto, the fan speed is automatically selected according to the mode of operation, set temperature and room temperature.

In cool mode, choosing Auto Fan will result in the following automatic fan speed selection:

Room Temperature

< Set pt-3°C

= Set pt-3°C

= Set pt.

= Set pt+3°C

> Set pt+3°C

Indoor Fan Speed

LOW

LOW

*

HIGH

HIGH

*Maintain current fan speed

Therefore, if the temperature set point is 20°C when cool mode is first entered in a room at 23°C, the indoor fan speed will be automatically HIGH.

The Indoor Fan Speed still remains at HIGH when the room temperature later lowers to 20°C.

When the room temperature falls further to 17°C, indoor fan speed changes to LOW.

If the room temperature rises to 20°C again, the indoor fan will still run at LOW speed. Indoor fan speed will not be changed to HIGH unless the room temperature rises further to 23°C.

In dry mode, the indoor fan constantly runs at low speed. The Auto Fan function is not available:

Room Temperature

< Set pt-1°C

= Set pt-1°C

= Set pt.

= Set pt+1°C

> Set pt+1°C

Indoor Fan Speed

LOW

LOW

LOW

LOW

LOW

In heat mode (Heat Pump Unit only), indoor fan speed is controlled as follows:

Room Temperature

< Set pt-3°C

= Set pt-3°C

= Set pt.

= Set pt+3°C

> Set pt+3°C

Indoor Fan Speed

HIGH

HIGH

*

LOW

LOW

*Maintain current fan speed

For example, if the set temperature is 20°C when heat mode is entered in a room at 17°C, the indoor fan speed will be automatically HIGH.

The indoor fan speed still remains at HIGH when room temperature later rises to 20°C.

When the room temperature rises further to 23°C, the indoor fan speed is changed to LOW.

If the room temperature subsequently falls to 20°C again, the indoor fan will still run at LOW speed. The indoor fan speed will not be changed to HIGH unless the room temperature dips further to 17°C.

When Sleep function is selected in manual operation, indoor fan speed will be fixed at LOW until the air-con is eventually turned off by sleep function.

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Fedders R407C service manual Indoor Fan Speed

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.