An EBS interface board is installed adjacent to the hot water heater. A U.L. listed pressure switch is installed at the hot water heater gas valve. Sensor wires are attached to the pressure switch to read “on” time for the gas valve. “On” time data is transmitted via the on board Transmitter, Repeaters, Receiver and to the Central Unit. The Receiver and Central unit, typically installed in the clubhouse, decodes transmissions from the Receiver and stores the meter readings for retrieval by Energy Billing Systems, Inc's billing computer.