ELECTRONIC CONTROL SEQUENCE OF OPERATION

Compressor and Reversing Valve Control

Active Mode

Compressor

Reversing Valve State

Cooling

On

De-Energized

Heat - Heat Pump

On

Energized

Heat - Electric

Off

 

Fan Only

Off

 

* The Reversing valve stays in the last state until a call for heat or cooling (see figure below)

Compressor Operation:

The reversing valve only changes when required to provide cooling or heat pump. The RV valve stays in it's last state until required to change.

Cooling Mode

Once the ambient temperature rises past the cool demand threshold (Cool Set Point + 1.5 ˚F) (see figure below), and the compressor is not locked out, the cooling cycle begins. As shown in the figure below, the fan is started 5 seconds prior to the compressor. Once the ambient temperature has been lowered to the cool set point (Cool Set Point minus

.25 ˚F), the cooling cycle starts to terminate by shutting off the compressor. After a 30 seconds delay, the fan is shut off. (See figure below for graphic details)

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Friedrich R-410A service manual Electronic Control Sequence of Operation, Compressor Operation
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R-410A specifications

Friedrich R-410A is an advanced refrigerant widely used in HVAC (Heating, Ventilation, and Air Conditioning) systems, known for its high efficiency and environmental friendliness. As a hydrofluorocarbon (HFC) blend, R-410A has become the preferred alternative to R-22, which is being phased out due to its ozone-depleting potential. One of the main features of R-410A is its high latent heat of vaporization, which allows for efficient heat transfer and improved cooling performance in air conditioning units.

Technologically, R-410A operates at higher pressures than older refrigerants, meaning systems designed for R-410A need to be built with more robust components to safely handle these pressures. This results in a more compact system design that offers enhanced performance and reliability. The dual-component nature of R-410A—composed of difluoromethane (R-32) and pentafluoroethane (R-125)—provides an optimal balance of thermodynamic properties, leading to superior energy efficiency, especially in variable speed applications.

In terms of characteristics, R-410A has a higher cooling capacity, which enables HVAC systems to effectively cool larger spaces or run more efficiently when cooling smaller areas. The refrigerant is non-toxic and non-flammable, which enhances safety during its use. In addition, R-410A has a lower global warming potential relative to other refrigerants, making it a more environmentally responsible choice for modern cooling systems.

Moreover, R-410A systems typically require less refrigerant charge due to their efficiency, contributing to reduced greenhouse gas emissions. The adoption of R-410A aligns with regulatory trends aimed at minimizing the environmental impact of refrigerants in cooling applications.

Overall, the Friedrich R-410A refrigerant embodies a combination of technology and environmental stewardship, making it a cornerstone of contemporary HVAC design. Its ability to provide effective and energy-efficient cooling solutions while being compliant with modern environmental regulations positions R-410A as the refrigerant of choice for engineers and installers focused on sustainability and performance in air conditioning systems.
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