We recently purchased a GE Panametrics PT900 Ultrasonic Flow meter to use on our retro-commissioning, optimization and commissioning projects.  Last week we tested it out on a 6″diameter steel condenser water pipe and were blown away.  It was easy to install the transmitters and configure the meter, within about 10 minutes we were logging data.  We are looking forward to using the temperature sensors to do some energy metering in the near future.  It is important to invest in the right tools, they enable us to accurately analyze system parameters like condenser water flow rate and then make adjustments to optimize system performance.