摘要 |
A commercial hot water system includes a hot water source, and a hot water delivery line connected between the hot water source and at least one plumbing fixture. A pump, enables circulation of hot water to and from the fixtures. A controller provides for turning on the pump in conjunction with an external signal, and a detector, preferably a temperature sensor, in conjunction with the controller, is effective in stopping the pump to prevent heated water from being circulated. |