A non-invasive thermal dispersion flow meter with chronometric monitor for fluid leak detection includes a heater, an ambient temperature sensor and a flow rate sensor which are configured to sense the temperature of a fluid in a conduit, and then monitor the flow of that fluid through the conduit. Based upon the ambient temperature sensor readings, the flow rate sensor and heater may be adjusted to optimize the operation of the system to detect leaks. Based on the sensor readings, the flow may be adjusted to prevent damage and leaks by relieving the system of excess pressure. Geographic location, occupancy sensors and occupant identifiers are used to control the system to facilitate operation and minimize leak damage when occupants are away.