I am planning to replace a WhisperFlo WFE6 with an Ecotech EZ EVSS15-NS. I currently have a mechanical timer that includes a "fireman's switch." To prevent damage to the heater, the switch turns off the heater 20 minutes before the pump shuts off. I've read the Ecotech installation and maintenance manual and can't find a similar feature. Do I just have to remember to turn off the heater at least 20 minutes before the pump shuts off? Or is there another method that would accomplish this?