STAFF REPORT - CITY COUNCIL/SUCCESSOR AGENCY/PUBLIC FINANCE AUTHORITY

Limitorque MX is an actuator system that controls flow through a valve for the effluent filter water to the clear well for each filter bed at the water treatment plant. The actuator controls the rate of flow control (RFC) and the RFC  controls all the valves. This in turn tells the filter water valves how much to open or close for each filter bed by a percent. In auto the filter RFC (Rate of Flow Control) automatically controls flow through the filter based on a percent demand which itself is based on overall plant flow. In manual the filter RFC (Rate of Flow Control) is set to a manual percent flow, which will not adjust itself based on overall plant flow.

The RFC’s are malfunctioning in auto which cause many problems relating to plant flow. It is causing either too high or too low of a flow through the filter with each problem causing other problems. Too high of a flow will cause other filters to lose flow. Too low of a flow will cause other filters to gain flow. This teeter totter effect will cause more than just the one filter to have drastic high and low flows, head loss or differential pressure and turbidity reads. All of which make it very difficult to run the water plant and for water to flow through the plant as it was designed to.

The actuators that are currently at the plant were the original valves when the plant was built. They have a very long life expectancy. However, staff was advised by Telstar and other tech companies that they are worn out and they can’t be calibrated correctly nor find replacement parts for them. Therefore, they need to be replaced.

The replacement of these 5 actuators were identified in the 2020 bond projects. Funds from bond proceeds will be used to purchase these items. Water Plant will be installing the valves.