Also known as the Four-Way Valve, the cycle reversal valve is used to reverse the function of the exchangers. The operation of the four-way valve for the winter cycle (heat pump) is based on simple thermodynamics – let the cold refrigerant pass to the outdoor unit and the hot one to the inside. For the summer cycle it would be exactly the opposite.
Movement of the piston
Most four-way valves work in the same way. The only difference is in the method used for the movement of the piston. The most commonly used method is that of the piston moved by the pressure of the refrigerant itself, commanded by an electromagnetic valve. On the inner faces of the two pistons there is always the pressure of the refrigerant gas at the compressor outlet. Through the solenoid valve, the pressure in the suction of the compressor is conducted on the outer face of one or the other piston, thus achieving its positioning depending on whether or not the electromagnetic valve is excited. The solenoid valve acts as a pilot valve, although nothing prevents designing the four-way valve with its piston directly coupled to an electromagnet.
Search Google for “best heat pump installer in my area” and consult with an expert now. Summarizing a bit, what makes our air conditioning equipment have a heat pump is simply a four-way valve, which depending on the cycle we want (acts in one way or another, sending the cold refrigerant or hot to one side or the other).
High Pressure Switch
As its name indicates, this type of pressure switch in the heat pump controls the high pressure of the circuit. In most cases it is usually manufactured with manual reset since if the pressure in the high circuit increases enough to cause the interruption of the compressor, the operation of the compressor and high pressure circuit can be normalized through the high pressure switch. It is usually a sign that anomalies have occurred that must be corrected to achieve a normal operation.
The most common causes that lead to an increase in the high pressure of the installation are usually the non-circulation of cold fluid for condensation or an obstruction in the installation, dirt in the condenser, which hinders the thermal exchange or non-condensable inside the circuit. If you feel that your heat pump or air-conditioning machine is not working properly, it is time to call the local company experts for a periodical check.