Is the too low light the only light on? Is it solid or flashing?
I am in Austin, so any turnaround on this will be fast. The too low red light can come on for 3 reasons- Pump ran 10 minutes and the controller has timed out, controller settings were erased and it has no timer (usually this is due to switching by another controller that is harsh or a power surge), if the too low blinks and too high is on solid, this indicates water damage and it only takes a drop, if the power supply tip landed in water and was plugged in wet, it will cause this, but minor damage can usually be repaired.