Abstract: Devices and methods are provided for improving the operation of the on-board generator during use of air-conditioning in motor homes so the generator runs only when the thermostat demands the A/C unit(s) to run, as opposed to conventional motor-home A/C systems that require running of the generator even during intermittent shut-downs of the A/C unit(s). Such devices are formed of a plurality of time-delay relays connected with additional components in a unique arrangement with typical motor home electrical wiring, thermostat, A/C unit(s) and generator.