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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 determines that the situation is under control and shuts the water being injected into the
basket (tumbler) off, the microprocessor display will read “S.A.F.E. SYSTEM WAS ACTIVATED,” and the
horn/tone will sound until reset manually.
To reset the microprocessor once the control displays “S.A.F.E. SYSTEM WAS ACTIVATED,” press the red
“STOP/CLEAR” key on the keyboard (touch pad).
S.A.F.E. SYSTEM WATER VALVE CHECK
The operation of the water solenoid valve can be tested to ensure that the water supply system and valve are
functional. Before attempting a system check, be sure that
ALL
water supply shutoff valves to the dryer are in
the OPEN position; the dryer
must be
in the “READY” mode with no cycle loaded or in progress.
1. Press and hold the red “STOP/CLEAR” key (while in “READY” mode and no cycle is in progress).
2. Press and hold the “A” key.
3. Water valve will open and water will be dispensed into basket (tumbler) area as long as both keys are held.
The Phase 7 non-coin microprocessor controller (computer) will prompt the user to perform a S.A.F.E. system
valve check at every 4000 hours to ensure proper functionality. At the 4000 hour mark, the control will wait for
end of the cycle and then will prompt the user to “PLEASE EMPTY TUMBLER, THEN PRESS THE
‘STOP/CLEAR’ AND ‘A’ KEYS TO TEST THE WATER VALVE.” When the ‘STOP/CLEAR’ and ‘A’ keys
are pressed, the control will activate the S.A.F.E. system water valve for 2-seconds, at which point the control
will prompt the user with the following message: “IF WATER DID NOT TURN ON, CALL FOR SERVICE.
THANK YOU.”
