ACTUATORS ... A PLUMBER'S BEST FRIENDBy all accounts, Earlen is a skilled plumber, but he’s quick to point out that a new generation of HVAC systems and components are now available that are designed to make him look good - and life a lot easier for both the installer and the building owner. He has, for example, been leading what he calls a ‘campaign to upgrade’ the dozens of older actuators used on the three-way mixing globe valves found on all the schools’ hot water lines that are used for both heating and domestic uses, particularly actuators.
For his upgrade campaign, Earlen chose TAC FORTA globe valve actuators.
ONE SIZE FITS ALLAccording to Earlen, the unit is particularly well-suited for the demands of his school buildings because of its versatility and ease of installation and operation. He needs, for example, to stock only a few models to accommodate any globe valve size from ½ to 6 in., so inventory costs can be kept to a minimum (of particular appeal to a frugal school district). And any FORTA can easily be set up to handle any common proportional input signal, whether it’s the 0-10 VDC typically output by the controllers used in Earlen’s schools, or 2-10 VDC or 4-20 mA, or even a floating or two position signal, simply by flipping a DIP switch. Mounting the actuator to the valve and configuring it to that valve’s stem travel is extremely easy as well, he said, and it can be done without any special tools or having to worry about disconnecting power already going to the actuator.
Additionally, the unit allows the user to establish, via a DIP switch setting, a desired valve position at control signal loss, anywhere from a completely closed (stem down) to completely open (stem up) valve position. Why is this important? “Say we temporarily lose our controller during the school day,” said Earlen. “We don’t want a valve to begin delivering a 140°F to 150° scalding hot flow of water to our buildings where a child might be washing their hands, but rather, a flow of colder temperature. This can be done with FORTA by establishing the desired ‘stem-up or stem-down’ position in advance. We’re ready even when our controllers aren’t.”