Blower Heat Off Delay Timings; Normal Sequence Of Operation; Power Up; Heating Mode - Maytag Amana MEC96 Series Installation Instructions Manual

1. Refer to the air flow table for your specific model
furnace
2. If a cooling or heat pump condensing unit is being
used in conjunction with this furnace, DIP switches
S1-1, S1-2, S1-3 are used to select the proper
cooling speeds to match the outdoor unit size.
Typical CFM requirements are 400 CFM / Ton.
3. Heating speeds are selected DIP switches
S1-4 & S2-1
1. Turn OFF power to the furnace.
2. Select the cooling blower speeds that match the instal-
lation requirements from the airflow table in this manual
or the Service Manual, If factory cooling speeds do not
match the installation requirements, the dip switch
settings must be changed from factory position
3. Turn ON power to furnace.
4. Verify proper temperature rise in heat mode and CFM
in cooling mode

Blower Heat Off Delay Timings

The integrated control module provides a selectable heat off
delay function. The heat off delay period may be set to 90,
120, 150, 180 seconds using the DIP switches provided on the
control module. The delay is factory shipped at 150 seconds
but may be changed to suit the installation requirements and/
or homeowner preference. Refer to the following figures for
switch positions and corresponding delay times.
PCBBF139 CONTROL BOARD
SWITCH
PURPOSE FUNCTION
GROUP
Heating Fan
S3
Off Delay
*Factory Setting

Normal Sequence of Operation

Power Up

• When power is supplied, the control will energize
the Red LED, microcomputer runs its self-check
routine.
• The control will check the status of the gas valve
circuitry.
• Line polarity is checked.
• The control then enters standby waiting for a call
for heat or cool.
• The Furnace status LED will display a slow green
flash signaling standby mode.
DIP SWITCH
1 2 3
90 OFF OFF
120 OFF
150 ON OFF
180 ON

Heating Mode

Call for 1st Stage Heat Only:
• On a call for first stage heat, the thermostat
contacts close signaling the control module.
• The microcomputer runs its self-check routine.
• The Amber LED will display a slow flash signaling
normal heat operation.
• The control module checks the high limit (and/
or auxiliary limit) switch(es) for normally closed
contacts.
• The control checks the low pressure switch for a
shorted condition
• The gas valve relay status is checked for proper
operation. Once the low pressure switch is detected
open, the inducer blower is energized at high speed
and the humidifier is enabled.
• The low pressure switch is checked for closure.
• Once the low pressure switch is closed, the pre-
purge period begins. The inducer will be energized
at high speed for the pre-purge period.
• Following the completion of pre-purge, the inducer
switches to low speed and the igniter warm up
period begins.
• After completion of the igniter warm up period:
a. Trial for ignition begins.
b. The first stage of the gas valve is energized.
• The igniter is de-energized when flame is sensed or
at the conclusion of the ignition activation period
(IAP), whichever comes first.
• When flame is sensed, the delay to heat on period
begins timing.
4
• After the delay to heat on period, the circulator
fan is energized at the low heat speed.
• The EAC contact is energized with the circulator.
ON
ON
Call for 2nd Stage After First Stage:
• The inducer motor goes to high speed.
• The pressure switches are checked for closure.
Closure of the second stage pressure switch will
energize the high fire stage of the gas valve.
• The high speed circulator output is energized.
NOTE: A call for 2
will be ignored, and a three amber flash code will
be displayed on the LED. This error code will only
be stored in memory once during a single power
cycle.
2nd Stage Satisfied, First Stage Still Calling:
• When the second stage of the thermostat is
satisfied, the inducer blower is reduced to low
speed which de-energizes the second stage of the
gas valve.
• After the high heat off delay expires, the circulator
is reduced to low heat speed.
• Note: A call for second stage without a call for first
stage will be ignored.
49
stage without a call for 1st stage
nd