Several interior components contribute to how an HVAC system works. The thermostatic expansion valve is a device that is designed for throttling the amount of refrigerant that moves through your air conditioning system’s evaporator. It regulates this flow based on monitoring the temperature and pressure inside the unit.

Thermostatic Expansion Valve Phases

As refrigerant moves through your air conditioning system, it will undergo several changes. The first passage that it makes is through the evaporator, and then, it moves through the compressor. The condenser is the next stop before it passes through the thermostatic expansion valve. From here, the refrigerant will again go through the evaporator and compressor to cool and condition the air that will be pushed back out into your home through your vents.

Thermostatic Expansion Valve Components

The same general components are used in the construction of any thermostatic expansion valve, but there can be some minor differences in how the part is made from brand to brand. In each valve, you’ll find a diaphragm, setting spring, orifice, and power source.

The valve operates by utilizing three different forms of pressure. They come from a bulb, spring, and evaporator. The bulb is located at the very end of the evaporator, and it will assess the temperature of the refrigerant. The diaphragm moves to these findings. The spring will provide pressure up against the diaphragm at a constant level. This counteracts the amount of pressure that is being provided by the bulb.

Internal and External Equalization

A thermostatic expansion valve uses either of two main types of pressure equalization. These are internal and external equalization. The external variety is the most commonly used, and it works for systems with more than one circuit. Monitoring large pressure drops is optimally completed with an external process.

You should always have your furnace and air conditioning installation, maintenance, and repairs completed by knowledgeable professionals who will ensure that your home is properly assessed and taken care of. That’s exactly what you’ll get when you enlist our expert team of technicians at Mountain View Heating. We also offer indoor air quality services and ductwork inspections and cleaning. We’ve been conscientiously serving customers throughout Bend and the surrounding areas for more than 40 years. Call us today to learn more about your thermostatic expansion valve or to book an appointment for our services.

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