Understanding Air Velocity Sensors

Dwyer Instruments offers a multitude of sensors for monitoring air velocity in HVAC systems. Some of this instrumentation has a simple construction (Pitot tubes, for example) while others are more complex, such as hot-wire anemometers.

The initial term and first “hot-wire anemometer” was developed back in 1914 by Louie Vesso King. He is also accredited for King’s Law, which mathematically describes heat transfer in air flows using a heated wire. As the air moves over the wire, it causes a loss of temperature in the wire and removes some of the wire’s heat energy. Continue reading “Understanding Air Velocity Sensors”

School HVAC Test & Balance Solutions

HVAC technicians test, adjust, and balance many different types of indoor environments, from clean rooms and hospitals to schools and offices. Within schools, it’s important that the HVAC system be run thoroughly and efficiently in order to promote learning and health, and to keep expenses down (allowing funds to be channeled into other educational avenues). Proper distribution of air flow can increase comfort, lower energy bills, and maintain a healthy indoor air quality. Continue reading “School HVAC Test & Balance Solutions”

What is Radon, and Why are We Testing for it in Our Homes?

For anyone who has recently purchased or sold a home, they may have noticed a radon inspection clause in the purchasing agreement. What is radon, and why are we testing for it in our homes?

Radon is an odorless, colorless gas that is naturally released into the environment as a decay byproduct of radium. Radium is a decay byproduct of uranium which can be found in certain types of rock, soil, or water. Some areas have higher concentrations of radon due to the soil composition which leads to additional testing for radon. Continue reading “What is Radon, and Why are We Testing for it in Our Homes?”

The Basics of Air Velocity Sensors

Stainless Steel Pitot Tube, Series 160

Dwyer Instruments offers a multitude of sensors for monitoring air velocity in HVAC systems. Some of this instrumentation has a simple construction (Pitot tubes, for example) while others are more complex, such as hot-wire anemometers.

The initial term and first “hot-wire anemometer” was developed back in 1914 by Louie Vesso King. He is also accredited for King’s Law, which mathematically describes heat transfer in air flows using a heated wire. As the air moves over the wire, it causes a loss of temperature in the wire and removes some of the wire’s heat energy. Continue reading “The Basics of Air Velocity Sensors”

Let’s Chat About Air Pressure Switches!

Air flow pressure switches and differential pressure switches work just like the light switches we have in our living rooms at home: when they are switched on, the switch makes contact, closes the circuit, and turns on. When they are switched off, the circuit is broken and power turns off. With air flow switches, instead of being manually switched, the air flow switch closes or opens the contact by reacting to changes in the air pressure at a pre-set actuation point, and turns on and off accordingly. These air pressure switches may be used to start/stop motors or fans, open/close dampers or louvers, sound alarms, and more. Continue reading “Let’s Chat About Air Pressure Switches!”