LawnMaster sprinkler timer isn”t keeping correct time

Q. The clock on the digital 12-station LawnMaster sprinkler timer I installed in 1996 loses time. If I set it to 1200 hours, it will lose several minutes, and up to a full hour, within three or four hours. It cycles correctly on manual; it’s just the time of day that lags. Do you have any ideas on how to fix it, short of replacing the unit? – Frank P., Spokane

A. In researching the answer to your question, I learned that your unit is a Lawn Genie LM-12. The manual for this timer is available electronically on the Lawn Genie Web site at www.lawngenie.com. You can also contact them at (800) 231-5117 for help in troubleshooting the timer.

It appears that a power interruption (power surge or electrical disturbances) caused the unit to malfunction. Depending on how the timer was wired, i.e., hard-wired or, as in your case, through a transformer, the power needs to be disconnected from the unit for at least 45 minutes to one hour. The factory calls this a “hard reset” and it returns the unit to its original factory settings.

The transformer should not be plugged into an outlet in a circuit that powers other high-powered devices such as a garage door opener, power tools, etc. These types of products and tools can cause electrical disturbances that can make the timer act abnormally.

Also check for loose wires at the controller and valves and at the transformer connection.

While the power is off, during a hard reset, would be a good time to replace the backup battery, which will help the unit maintain time and day up to 60 days during a power failure. However, the backup battery will not operate the valves during a power outage.

Even though this unit was designed to insure operation of the controller in the event of any unexpected electrical disturbances, power loss or valve failure, a hard reset in most cases will solve abnormal issues.

If you follow the troubleshooting tips described here and the timer still fails, then it’s time to retire the timer and install a new one. They are fairly inexpensive and this will give you an opportunity to get an updated unit.