Operation MQ starts when it senses a minimum flow of 0.8 GPM flow or a pressure drop to 30 PSI (whichever occurs first). It then monitors the output to keep the pump running until a very low flow rate is reached (approximately 1/2 GPM). The MQ pump has a small built-in pressure tank to ensure that water is readily available from the tab. When water is required the pump automatically starts and no loss of pressure will be felt. It also features a built-in check valve. The pump is cooled by the pumped water which eliminates the need for a noisy fan. Because the pump is self-cooling you don't need to have free space around the pump for cooling purposes. Because the pump will keep running down to very low flows, this overcomes problems of cycling. Protective Features Built-in dry-run protection. If the pump runs dry it automatically stops. It will then attempt to restart for a maximum of 24 hours until water is available from the source. If more than 24 hours pass without water it must be restarted manually. The auto reset function can also be disabled. Built-in thermal protection. If the pump overheats ( dry running, overtemperature of liquid, overloaded motor, locked rotor condition) it immediately stops. After a 30 minute cooling-down period, the pump will automatically restart.