Optimization of pressure sensors for HVAC systems

Industrial, business and residential sectors all have one thing in common: the need for heating and cooling. Whether it’s a chemical storage area requiring a constant temperature and complex filters, or an office block with hundreds of employees working all day, maintaining temperature control is essential to any operation.

To achieve this, you can use your HVAC system. They come with a variety of sensors, depending on your individual requirements and the complexity of your system. Take pressure sensors, for example – they are responsible for monitoring air pressure levels in filters and other devices to ensure the HVAC system is working properly and alerting technicians in the event of blocked filters or more serious issues.

Compressors for cooling function

The air conditioning unit in an HVAC system typically relies on the use of refrigerants to cool a space. Warm air is drawn through a set of coils containing refrigerant, which absorbs that heat. The refrigerant is then compressed into a hot, high-pressure gas and passed to a condenser unit where that heat energy can be released.

Pressure sensors can start or stop the compressor based on measured internal pressure values ​​to ensure smooth and efficient system operation. But they also perform a key safety check.

Small holes or cracks in the coil can cause refrigerant leaks. Depending on the severity of the leak and the type of refrigerant, they can be difficult to detect by sight or smell, and the system may overwork to compensate. A large amount of refrigerant is essential to keeping the air conditioning system running, but any leaks can also be a potential safety hazard. Common refrigerants like Freon can be harmful, especially in high concentrations or in small, confined spaces. As such, pressure sensors can be used here to monitor the compressor’s status and signal potential pressure drops that could indicate a dangerous leak.

Precise temperature control

Another example that uses pressure sensor technology is a variable air volume (VAV) system that provides a varying volume of airflow rather than a constant air volume (CAV). VAV systems use additional sensors at the inlet to open or close internal dampers, thereby regulating the airflow. These adjustments can be made based on a variety of control parameters, compared to a CAV system that can only operate in a constant, maximum, or “off” state. This results in a more precise approach to temperature control using VAV. In addition, variable airflow also uses lower fan speeds, resulting in quieter operation as well as reduced energy consumption.

Because a VAV system offers more sophisticated control, it is possible to integrate the HVAC system with additional devices to unlock additional benefits. For example, connecting to occupancy sensors can allow the HVAC system to adjust between ideal temperature levels based on the current use of the space.

Electronics optimization

In essence, a pressure sensor consists of a measuring element, a processing unit, and a communication module. The signal measured by the sensor will usually be in analog form and must be conditioned and digitized before being processed or transmitted to other devices.

You can get standard off-the-shelf ICs with the basic functions to perform this signal conversion task. However, for an optimized system that stands out from the competition, it is often better to use an ASIC (Application Specific IC).

An ASIC is a specially designed chip designed specifically for its application—in this case, its specific role in HVAC system components. By offering sensor-specific integration, ASICs offer improved performance over commercially available alternatives, as well as reduced power consumption through performance optimization.

ASIC integration also offers the benefit of system calibration. Calibrated data can be stored in the onboard OTP/flash memory, allowing individual sensors to be calibrated and raw pressure data to be corrected. This ensures precise measurements even over extended periods of operation and helps maintain the efficiency and reliability of the entire HVAC system.

When it comes to off-the-shelf integrated circuits, obsolescence can be an area of ​​concern. Standard IC manufacturers can discontinue production at any time, whether that’s the result of a particular silicon process becoming obsolete or a significant drop in IC volume. In contrast, ASICs are designed with obsolescence in mind.

The choice of silicon process is made with careful consideration of supply and the durability required by the product. And in the event that the process becomes obsolete early, solutions are presented to the customer in a timely manner to ensure continuity of supply. This may involve purchasing LTB wafers or moving the design to a completely new process. Working with an experienced ASIC supplier such as Swindon means that customers are involved and guided through the decision-making process, resulting in the creation of a complete obsolescence plan.

HVAC systems can be found in a variety of environments, whether industrial, commercial, or residential. Regardless of the final point of installation, it is essential that the HVAC system offers the same high level of performance to everyone it serves. By optimizing the design from the chip level, device manufacturers can ensure that their system offers performance levels that are a step above the competition.

To learn more about Swindon Silicon and its custom IC solutions, please visit https://www.swindonsilicon.com/news/