| 摘要 |
PURPOSE:To ensure a resetting even when the operation is suspended due to a misfire by inserting a non-lock switch, which, in a sequence control circuit of a heat exchanger, is interlocked with a power switch so as to be turned off only when the power switch is turned on or off, in series with afore-said switch and a low-temperature thermostat which are arranged parallelly. CONSTITUTION:A non-lock switch 5b, which is opened only at the moment when a lock switch 5a is turned on or off and maintains its ON condition thereater, is connected to a low-temperature thermostat 6 and a lock switch which are parallelly connected. By such a constitution, even if a sequence control circuit 9 suspends its operation due to a misfire for some reason while the low-temperature thermostat 6 stays on, the resetting operation can easily be done by operating the main switch 5 only to restart the sequence circuit 9. |
