How Pressure Sensors Increase Efficiency and Optimize System Performance

Pressure sensors are valuable tools that allow property owners to reduce their expenses and create more comfortable spaces for building occupants. With the right sensors, you can monitor pressure in your plumbing, heating, ventilation, and cooling (HVAC), and other systems. However, with so many products available on the market, it can be difficult to know which are worth the investment. Exploring the use and function of different pressure sensors is the first step.

Table of Contents

• The Purpose of Pressure Sensors and Transducers
  • Pressure Sensors
  • Pressure Transducers
• Comparing Wet and Dry Pressure Sensors
  • Dry-to-Dry Pressure
  • Wet-to-Wet Pressure
    • True Wet-to-Wet Pressure
    • Calculate Wet-to-Wet Pressure
  • Wet-to-Dry Pressure
• Pressure Concerns for Commercial Spaces
  • Measuring Duct Static Pressure
  • Monitoring Air Pressure
  • Maintaining Optimal Water Pressure
• Sensor Solutions for Energy-Efficient HVAC Systems
  • HVAC Sensors
  • Transducers with Bluetooth Capabilities

The Purpose of Pressure Sensors and Transducers

People sometimes use the terms sensor and transducer interchangeably, but that's not entirely accurate. Although the definitions overlap, sensors and transducers help you achieve different goals.

Pressure Sensors

A pressure sensor is a device that detects the force of pressure that a substance or body exerts on it. It sends a pressure value signal to a remote location, where an operator takes readings and tracks system performance.

Advanced pressure sensors are often components of larger systems that read pressure levels and control the system based on the reading. For instance, depending on the pressure level, the system might automatically turn certain elements on or off.

These kinds of sensors have a wide variety of applications, such as:

• HVAC: Sensors can detect air moving through ducts, filters, and other systems. They provide differential air pressure measurements that are useful for regulating airflow and improving operational and energy efficiency.
• Automotive: Airbag systems, engine manifold systems, and tire pressure monitoring systems have pressure sensors for safety reasons. They monitor these systems and warn drivers when potential issues could pose a hazard, such as a failed airbag deployment.
• Healthcare: Professionals in the healthcare industry rely on pressure sensors to provide care for their patients. Sensors allow them to monitor blood pressure, administer respiratory therapy, and perform dialysis.
• Aerospace: Fluctuations in air pressure can wreak havoc on a flight. Pressure sensors provide altitude and airspeed measurements, as well as fuel pressure and cabin pressure monitoring.

When purchasing pressure sensors, it's important to consider not only which of these applications is most relevant but also what level of range and accuracy you need to achieve.

Pressure Transducers

Like sensors, pressure transducers take measurements. However, while sensors detect pressure and convert it into an electrical signal, transducers monitor electrical signals and convert them into proportional voltage. A transducer reads the pressure in a fluid system and delivers output as voltage or amperage to a remote location, which enables monitoring and automated or manual control of the system.

These are some of the most common types of pressure transducers:

• Strain gauge pressure transducers convert physical quantities into mechanical stress.
• Capacitive pressure transducers measure changes in the distance between diaphragms as differential, absolute, or gauge pressure.
• Piezoelectric pressure transducers use quartz crystals or ceramic to create electrical charges that are proportional to the pressure applied.
• Optical pressure transducers measure pressure with changes in light.
• Resonant pressure transducers convert resonant frequencies into electrical signals.
• Potentiometric pressure transducers have wipers that change positions when pressure is applied.

The kind of transducer you use differs based on the environment and application. However, they're helpful for measuring pressure in both wet and dry media, such as plumbing runs and air or gas ductwork.

Comparing 3 Styles of Dry and Wet Pressure Sensors

Although they serve the same basic purpose, sensors that detect dry pressure and wet pressure have unique designs. Knowing the difference between them helps you make a more informed decision about which type is most appropriate for your needs.

1. Dry-to-Dry Pressure

Dry-to-dry sensors can only take readings of air or non-corrosive gas. They use electrical sensors attached to a single linear diaphragm that moves in whatever direction the pressure is moving. As a result, they're primarily used for very low-pressure applications, including cleanrooms, leak detectors, and isolation rooms.

2. Wet-to-Wet Pressure

Wet-to-wet pressure sensors, on the other hand, measure liquid pressure. Some use a single diaphragm like a dry-to-dry sensor, while others use two different sensors in different positions. They can handle relatively high-pressure systems and are commonly found in HVAC systems, where they monitor the status of the filter, chiller efficiency, pump operation, and strainer baskets. Within the category of wet pressure sensors, you can choose between true and calculated wet-to-wet pressure.

What Is “True Wet-to-Wet Pressure”?

As a general rule, true wet-to-wet pressure is more accurate. Both sides of this sensor are connected to a diaphragm that can move in either direction. Because it uses a single piece that's connected on both sides, readouts are very precise, with little to no concern about human error. As such, it's appropriate to use it in flow measurement systems, liquid level measurements, and pressurized tanks.

What Is “Calculated Wet-to-Wet Pressure”?

Calculated wet-to-wet pressure sensors have a much lower rate of accuracy. This is primarily because they use two sensors that operate independently of one another. One side is calibrated for high pressure and the other for low pressure, and a small error in calibration can skew readings and make them inaccurate. These sensors can only measure pressure in a single direction, so they're typically only used in systems where the pressure flows one way. For example, a calculated wet-to-wet pressure sensor might be useful for measuring a pump's supply and return rates.

3. Wet-to-Dry Pressure

Wet-to-dry pressure sensors can handle extremely high-pressure systems, including those in industrial and aerospace applications. One side of the sensor uses a metal diaphragm to push against liquid, while the other is exposed to air or non-corrosive gas. They're frequently found in airflow sensors and to test benches, monitor filters, and verify airspeed.

Pressure Concerns for Commercial Spaces

Although pressure is an important factor in any type of building, commercial buildings can be especially challenging because of their size and complexity. Addressing different types of pressure issues ensures that you won't face costly property damage or inadvertently cause harm to building occupants.

Measuring Duct Static Pressure

Duct static pressure, the resistance of airflow through an HVAC system, can have a major impact on a building's heating and cooling. Pressure levels can vary due to issues such as:

• Poorly constructed ductwork
• Improper duct and system sizing
• Incorrect, missing, or clogged air filters
• Low fan speed

When these or other problems cause the static pressure in a duct to be too high or low, systems can become loud and distracting. Even worse, they can run for unnecessarily long periods, increasing energy bills and straining the equipment.

Beyond those expenses and inconveniences, incorrect static pressure can also affect temperature. Because the airflow is uneven, some rooms or spaces might become overly hot or cold. Likewise, if the air isn't circulating correctly, it may reduce the indoor air quality. This is especially concerning in commercial buildings and schools, as research shows that indoor air quality affects productivity and cognitive function.

Monitoring Air Pressure

Although people often think of air as being weightless, it actually exerts an enormous amount of pressure on everything it touches. Measuring air pressure is important not only to understanding weather and science but also to creating safe, efficient commercial environments.

The factors that affect air pressure include:

• Temperature: High temperatures cause lower pressure, and vice versa.
• Altitude: Lower altitudes usually experience higher air pressure because the spread of molecules is denser.
• Humidity: When humidity levels rise, the pressure level rises with them.
• The planet's rotation: Generally speaking, places closer to the Equator have lower pressure levels than polar areas.

To measure barometric pressure, scientists and weather specialists use barometers, which are absolute pressure sensors. Air pressure affects the mercury inside a barometer, with the force of the weight of the surrounding molecules causing the sensor to rise or fall.

The commercial world typically uses differential pressure sensors. They allow businesses to monitor liquid levels in industrial units, such as vats or other containers. They're also an effective way to identify leaks in water or gas pipes and can help automate airflow in HVAC systems.

Maintaining Optimal Water Pressure

Water pressure is a major concern for commercial property owners because it can have both short and long-term consequences. For instance, low pressure often occurs when pipes are leaking, clogged, or corroded. When pressure is too low, it's more than just an inconvenience. It could prevent your fire sprinklers from operating correctly in the event of an emergency.

High water pressure can severely damage pipes. It can occur due to thermal expansion, closed valves, or malfunctioning pressure regulators. According to a recent study, lowering and controlling water pressure could decrease the number of pipe breaks in a system by 18% to 30%.

The ideal pressure in a building is typically between 40 and 80 PSI (pounds per square inch), but your ability to achieve and maintain that pressure depends on the quality of your infrastructure. Installing wet differential pressure sensors allows you to measure the PSI inside your plumbing system and makes it easy to identify changes in water pressure that could suggest an underlying problem.

In addition to sensors, there are many other tools that help control your water pressure, such as:

• Pressure-reducing valves
• Backflow preventers
• Booster pumps
• Expansion tanks

Using one or more of these solutions could help you avoid the issues that lead to low or high water pressure, and adding sensors to your system tells you whether everything is performing correctly.

Sensor Solutions for Energy-Efficient HVAC Systems

According to the Office of Energy Efficiency and Renewable Energy, around 30% of energy used in commercial buildings is wasted. Sensors can help reduce that waste while also empowering commercial property owners to achieve significant cost savings and make building occupants healthier and more comfortable.

HVAC Sensors

When an HVAC system doesn't operate correctly, it can result in serious financial losses and poor air quality. Fortunately, HVAC technology has progressed to the point that it's much easier to monitor and optimize your system's performance.

Pressure sensors play a central role in creating a high-efficiency HVAC system. Along with air ducts, they're especially crucial in boilers and chillers because they allow operators to see when pressure levels are rising or falling unexpectedly. A shift in pressure could indicate a leak, equipment failure, or clog. The ability to quickly address these issues prevents further damage to the HVAC system.

Other types of sensors can also help you achieve HVAC energy efficiency. For example, temperature sensors monitor ambient room temperature and return and supply ducts so the operator can adjust the settings. Occupancy sensors serve a similar purpose, providing data about when rooms are most and least likely to be in use so that operators can plan cooling and heating accordingly.

Transducers With Bluetooth Capabilities

Accessing sensors and transducers can be difficult for HVAC technicians and operators, particularly if they're duct-mounted. A transducer with wireless Bluetooth eliminates this problem by allowing access from any location.

Veris offers the PX3 transducer, a Bluetooth-enabled device that can take either air pressure or velocity measurements. It pairs with the Veris Sensors app, where you can create, select, and store parameters remotely.

The PX3 transducer has multiple applications, including:

• Building and room pressure
• Duct static pressure
• Differential pressure
• Filter status

The PX3 is also a high-accuracy transducer with multiple precise pressure and velocity measurement options, and it allows you to maintain perfect calibration and reduce callbacks. It's safe to use in a variety of environments because of its excellent durability and water-resistant housing.

Whether you're concerned about HVAC efficiency, indoor air quality, or minimizing water waste, Veris can help. Our complete line of high-quality pressure sensors is accurate, easy to install, and affordable. Reach out to our expert team to learn more about how pressure sensors can enhance your system performance.