What Is a Thermostatic Expansion Valve?

October 20, 2021
Thermostatic Expansion Valve in Deptford, NJ

A thermostatic expansion valve is a plumbing fixture that can be mechanical or electronic. It is usually found in an exterior wall of the property, and it conveys all the water used for heating and cooling to a central location, called the boiler house. A thermostatic expansion valve is commonly used to regulate pressure in a line to achieve the required pressure at any point along the pipe. For example, if you have a gas line that is being pressurized, but you have no idea where that pressure should be, then an expansion valve would be an ideal solution. The expansion valve will allow gas to flow until it stops, which would create the required pressure at the desired point because it will not allow air into the line.

This device helps to prevent backflow by providing a small water-tight seal. It also provides temperature and pressure relief for both boilers and hot water systems. Thermostatic expansion valves are used throughout the building trade, from residential to industrial. These devices help homeowners stay on top of their cooling and heating systems and reduce energy costs.

Types of Thermostatic Expansion Valves

1. Internally Equalized Thermostatic Expansion Valves

The expansion valve uses the internal pressure of the system to determine the point of flow rather than a set point. The internal pressure is adjusted with a pneumatic or electromagnetic controller depending on the particulate’s direction. The underwater part of the thermostatic expansion valve is used to connect the piping to a water seal that allows water to flow into a piping system or a hot water system.

2. Externally Equalized Thermostatic Expansion Valves

The expansion valve uses pressure from outside the system to determine when to shut off and allow flow. These valves cannot release any of the pressure once it has been released into the system. This prevents unwanted gas or particulate from entering the system.

Thermostatic expansion valves perform several different tasks, which include:

1. Conductive

The thermostatic expansion valve is designed to allow water through the valve only when the temperature is suitable and it will conduct electricity within itself. It is designed in such a way so that the thermostatic expansion valve remains cool and does not conduct electricity when it is hot. It has a built-in safety device that stops it from conducting electricity when it senses high temperature. The thermostatic expansion valve is used to modify the flow of water from the hot to cold water lines for regulating the hot and cold temperatures of water.

2. Pressure Control

Thermostatic expansion valves regulate the flow of water in a line when the pressure in the pipe is different than desired. The expansion valve will allow water to be pumped greater than it usually would have. Pressure Control is used to provide an increased flow with a pump when the pressure in the line is too low. This would be done to prevent a pump from cavitating and provide extra pressure for fire protection and sprinkler systems. Pressure Control is also used when there is a higher pressure of water than desired. This would be done to prevent over pressurizing the system and damaging the equipment in the line.

3. Thermostatic Control

Thermostatic expansion valves can function as thermometers or delicate temperature regulators. This control helps maintain the temperature of the building. The expansion valve will allow water to flow through based on the equipment’s amount of heat. In most cases, water does not flow through the valve when not generating heat and then flows when things start to get warm. This is a safety feature for most building owners and managers. This setting can be verified by checking the pressure in the valve’s water supply pipe.

4. Hot Water Supply and Return

The thermostatic expansion valve is the main point of the hot water system. It is used to regulate the quantity of hot water being used throughout the entire home or building. It also helps to ensure that the correct water temperature is being supplied at any given time, which helps prevent damage to certain appliances depending on their design.

Thermostatic expansion valves are helpful in several ways. These valves are designed to keep the building safe by preventing damage from overheating or over pressurizing the system. Thermostatic expansion valves can be used to upgrade equipment in the building, prevent leaks, reduce energy costs, and improve the overall environment. If you are looking for more information about your heating and cooling supply, contact us at JAMCO Heating & Air Conditioning. We offer heating and cooling maintenance, repair and installation as well as mini-split and sheet metal services in Deptford, NJ, and the surrounding area.

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