YORK YK — Program Initiated Reset

The display shows PROGRAM INITIATED RESET. In the manual's printed example the message carries a time stamp in front of it: MON XX:XX AM - PROGRAM INITIATED RESET. The shutdown table lists the same message as Program Initiated Reset; these are the only spellings used for this message in the manuals.

This is a cycling shutdown: the watchdog timer circuit has reset the software program, and the chiller shuts down as a result. The manual explains the mechanism this way — the Micro Board did not receive a hardware-generated interrupt on schedule, the typical case being an Analog/Digital Converter interrupt. When the time needed to step through the program is longer than allowable, the watchdog timer circuit resets the microprocessor and the software program is initialized at its beginning. Because it is a cycling shutdown rather than a lockout, the unit comes back by itself, as described under Reset below.

• The watchdog timer circuit has reset the software program — the shutdown cause listed in the manual's Table 1.
• The Micro Board did not receive a hardware-generated interrupt on schedule; the typical interrupt is an Analog/Digital Converter interrupt.
• A Micro Board hardware failure — the manual says the message is indicative of this.
• Electrical noise on the Micro Board.

No reset action is required. The manual's action for this message is simply: The chiller will automatically restart. No key-press reset procedure is described for this message; the unit returns to operation on its own after the cycling shutdown.