Flow Monitoring in Chiller Applications

In the world of building automation, Dwyer Instruments continues to make strides in releasing products that enhance energy management. Chiller systems are at the core of air conditioning and climate control in the building automation market. Air conditioning systems will typically use chilled water through heat exchange coils to condition the air in desired rooms/zones throughout a building. This water is then recirculated into the chiller to be “re-cooled” and pumped back into the process. The primary trouble lies in monitoring the water flow and maximizing efficiency throughout the process. Many customers find themselves wanting to monitor the chilled water flow to ensure accurate power consumption and efficiency of the chilled water pumps. Many technologies are available and they all have their pros and cons. Dwyer Instruments offers Paddlewheel Flow Sensors, Ultrasonic Flow Meters, and the recently added Electromagnetic Flow Sensors. The paddlewheel flow sensors are proven technology, but since they are a mechanical device with moving parts, this introduces potential “wear and tear” over time. Ultrasonic Flow Meters are great for applications where there is no available downtime for installation of a paddlewheel flow sensor. These units are non-intrusive and strap directly onto the process pipe. The biggest concern with ultrasonic technology lies with the initial commissioning time and cost of the sensors. Ultrasonic technology is typically the most expensive of the three flow sensors; additionally, ultrasonic flow sensors may not provide the accuracy that is necessary when trying to maximize the efficiency of your process.
The Series IEFS Insertion Electromagnetic Flow Sensor offers the best of both worlds and addresses these concerns. This is an insertion style flow sensor, but does not have any moving parts. Furthermore, this is suitable for both clean and dirty liquid applications. This flow sensor is offered with a standard NPT connection and available hot-tap option. The hot-tap option allows for this insertion sensor to be installed onto a pressurized system that is still under full operating conditions. Whether there is no available down-time maintenance, or it is a 24-hour occupancy building that can never be shut down, the hot-tap allows for ease of installation. This flexibility allows you to install a flow sensor without having to completely re-pipe a system and do a standard tee installation. The IEFS will also be more accurate than ultrasonic technology and more responsive. It is this increased accuracy and responsiveness that will aid in maximizing your systems overall efficiency; ultimately saving you from excessive energy consumption and added cost. The IEFS is offered in both brass and 316 stainless steel bodies, with a pulsed output. Dwyer also offer our Series BAT Blind Analog Transmitter that will convert the pulse output of the IEFS to an analog 4-20mA signal to run back to a DDC system. If you require local indication, we offer the Series RTI Rate Total Indicator that will convert the pulsed output to a 4-20mA signal, as well as provide a local display for flow rate and totalization. Dwyer has also released the Series IPFS Paddlewheel Flow Sensor that is compatible with the Blind Analog Transmitter and Rate Total Indicator. This paddlewheel flow sensor is available with the hot-tap feature and gives a cost effective alternative to the electromagnetic flow sensor. All-in-all, energy efficiency and cost savings are variables that everyone would love to maximize. Implementing these flow sensors into your process will allow for control, monitoring, and confirmation that your process in running efficiently.