Maytag Neptune MAH3000 Service Manual page 116

INPUT MODIFICATIONS DEFINED
PRESSURE SWITCH INPUT
The pressure switch is a two level pressure switch. (Figure 4-2) The low level contacts
provide a path for a 24 VDC sensing circuit, the high level contacts provide an electrical
path for 110 VAC to the water valve relays on the board. Another sensor on the board
monitors the high level circuit to determine when the high level is reached and the
circuit is opened. Thus, shutting off the water valve relays.
During wash fill, the low level of the pressure switch is sensed with 24 VDC and provides
an indication to the control board the water level has satisfied the low level. Once
satisfied, the 24 VDC circuit is opened. The board then opens the water valve relays and
shuts off the water valves.
During rinse fill, the high level provides an indication to the machine control as to
whether the high water level has been reached. When the water level switch is satisfied,
the pressure switch circuit is opened and power for the water valves is no longer passed
through the machine control.
TEMPERATURE SENSOR INPUT
A thermistor is located in the water valve
to monitor the blended incoming water
temperature. The machine control uses
this input signal to regulate the water
temperature with the warm or cold wash
and warm rinse temperature selections
(See Water Valve Outputs).
On the MAH7500 model, another
thermistor is located on the heater
assembly. The machine control board
uses this input signal to maintain the
water temperature in the sump area of
the outer tub, by cycling the heater on/
off.
16010486 (16008373-05)
Revised 02/01
Figure 2
DOOR LOCK SWITCH INPUT
When input is present, this is indication
the washer door is locked. The machine
controller will not command the spinner
to tumble or spin when the door lock
input is not present.
If the door is opened during a cycle,
the control will pause the cycle on the
MAH5500B.
Section 2. Washer Controls Overview
©2001 Maytag Appliances Sales Company
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