The Armstrong 24-hour timers provide On/O pump control according to preset operating times in order to increase comfort and improve the overall e ciency of domestic hot water re-circulation systems. The 24-hour timers are designed for use with Armstrong circulators installed in indoor hot water re- circulation applications. Typical timer applications will cycle the pump at preset times, allowing the user to select operation of the circulating pump during high peak usage periods in order to decrease the delivery time to outlet fixtures and reduce wasted water. The timer control is programmable to 1⁄4 hour intervals within a 24-hour time frame utilizing a user friendly analog clock timer with hour and minute hands, two directional arrows, and am/ pm time setting.