American Dryer Corp MDG75PNH, MDG75MNV installation manual F.E. System Theory of Operation

Models: MDG75MNV MDG75PNH

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WARNING: If the water in the supply line or water solenoid valve freezes, the S.A.F.E. system will be INOPERATIVE!!

The manual ball cock shutoff valve must be located outside of the dryer at a distance from the dryer where it is easily accessible.

3.Electrical Requirements

No independent external power source or supply connection is necessary. The 24 volt power to operate the S.A.F.E. system is accomplished internally in the dryer (from the dryer controls).

WARNING: Electrical power must be provided to the dryer at ALL times. If the main electrical power supply to the dryer is disconnected, the S.A.F.E. system is INOPERATIVE!!

S.A.F.E. System Theory of Operation

While the dryer is in an idle state, or 20-seconds after the heat turns off, the Phase 7 control monitors the thermistor probe, located in the top of the basket (tumbler) chamber, and records the minimum temperature. If the minimum recorded thermistor probe temperature is greater than 120° F (48° C) and the control detects a 50° rise in temperature, this will be the trip point and the S.A.F.E. system routine will activate.

While a drying cycle is in process and the heat has turned on at least once, the Phase 7 control monitors the exhaust temperature transducer. If the drying cycle temperature set point is set greater than 160° F (71° C) and the control detects an exhaust temperature rise 25° F greater than set point, this will be the trip point and the S.A.F.E. system routine will activate. If set point is below 160° F (71° C), the trip point will be 185° F (85° C).

Once the S.A.F.E. system routine is activated, the control will display “S.A.F.E. SYSTEM ACTIVATED” and water will be injected into the basket (tumbler) chamber. Any time water is being injected into the basket (tumbler), the basket (tumbler) drive will turn the load for 1-second every 15-seconds. This process will continue for a minimum of 2 minutes. After the 2 minutes have elapsed, the control will check if the temperature remained above trip point; if so, the water will remain on. The control will continue to check if the temperature is above trip point every 30-seconds. If the water has been on for a constant 10 minutes, the water will be turned off, regardless of the temperature, and the control will display “S.A.F.E. SYSTEM WAS ACTIVATED”. If the temperature has dropped below trip point, the control will turn off the water prior to 10 minutes.

System Reset

After the microprocessor controller (computer) determines that the situation is under control and shuts the water being injected into the basket (tumbler) off, the microprocessor controller (computer) display will read “S.A.F.E. SYSTEM WAS ACTIVATED”, and the horn/tone will sound until reset manually.

To reset the microprocessor controller (computer) once the control displays “S.A.F.E. SYSTEM WAS ACTIVATED”, press the red “STOP/CLEAR” key on the keyboard (touch pad).

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Maytag Co.

113394 - 8

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American Dryer Corp MDG75PNH, MDG75MNV installation manual F.E. System Theory of Operation