Feature scale in the mid-to-late 1800s , smoke detection was patented at the start of the 1900s , infrared technology came online in the 1940s and motion sensors were first used in the 1950s .
The sensors of old , were of course far different from the sensors we see today ; which come in nano-technology form , such as what is seen in the latest HVAC window applications that aim to contribute to managing a buildings heat loads or energy conversion techniques . Compared to 20 years ago , there is a far broader requirement for digital connected technology today , because with that comes data , and data can be translated or converted into many more functional aspects today that holistically improve all technologies and also opens up integration opportunities that have become far more important to clients than before , and tie into their digitising strategy .
HVACR systems have become reliant on these clever devices that perform the function of verifying operational conditions and improve performance . Through sensors in a building the occupant health , safety , comfort , and productivity can be monitored and improved , or , in a refrigeration application for example , are involved in several measurement points to ensure that system function is in order and that produce is kept at the right temperature . Data gathered from sensors further offer the ability to see historic events and play a role in predictive future events .
Given their obvious importance , sensors that are faulty or out of calibration can affect the ability of any system , process , or action to be completed as designed and with the holistic drive around the world to improve every aspect of our living , comfort and how we do and make things , ensuring that sensors are running efficiently , and smoothly is critical . The slightest variations could ruin a batch of processed foods in the cold chain or inaccurate readings could lead to the transmission of airborne pathogens or even death due to gas leaks or smoke detection failing . Sensors therefore are said to also be key in avoiding mishaps .
COMMON SENSORS IN HVACR Given the supposed endless range of sensors and metering devices available , what follows are some of the most common , or critical sensors used in the sector , where they could be used and some important highlights of their requirements :
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Temperature sensors and temperature probes are used in all HVAC & R applications – some of which require extreme sensitivity .
Many commercial applications make use of in-duct CO₂ sensors .
These sensors can measure extremely high and low pressures in air and fluid applications offering precise measurement of
pressure , differential pressure , and velocity . Monitoring the pressure drop across filters is known to be an essential approach to reducing energy costs and preventing unnecessary load on air-moving equipment . Various case studies exist , illustrating the use of sensors versus not , produces significant energy savings .
In large buildings , the fan / air circulation portion of the HVAC system may include a device to regulate the static pressure developed by the fan .
In addition to being able to be permanently installed in a system , some pressure sensors may be used by service technicians for maintenance or trouble shooting that can identify ‘ leaks ’ and save the building owner money .
• Pressure sensors Pressure sensors are used in compressors , boilers , coolers , heat recovery systems , air handling units and variable air volume systems . They typically monitor components such as filters for drops in pressure which may indicate that there is a fault or that the system requires maintenance through some type of alert mechanism . The ability to monitor pressure is also useful for optimising air flow , heating , or cooling , and so on .
• Temperature sensors Temperature sensors measure air and fluids and can signal adjustment requirements to the system ( controller ) based on the programmed setpoint and therefore preventing wasted energy . Once could also use the sensor ’ s produced data to learn about a particular room ’ s conditions over time .
Incorporating temperature sensors would also prevent a system from running harder than required . Accurate and
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