Operating Instructions - Rheem H2AC Installation Instructions Manual

E. First Stage and Second Stage Called Simultaneously:
1. Zone thermostat contacts close, a call for first stage (low fire) and second stage
(high fire) heat is initiated.
2. Control runs self check.
3. Control checks the high-limit switch for normally closed contacts, each pressure
switch for normally open contacts, and all flame rollout switches for continuity.
4. Control energizes each low-fire inducer.
5. Control checks each pressure switch for closure.
6. If each low-fire pressure switch is closed, the control starts a 30 second prepurge.
If either switch is still open after 180 seconds, the high-fire inducers will be ener-
gized until closure.
7. After prepurge timeout, control initiates spark for 2 seconds minimum, 7 second
maximum ignition trial, and initiates 45 second second stage warm up timing.
8. Control detects flame, de-energizes spark and starts a 45 second indoor blower
delay on timing.
9. After a fixed 45 seconds indoor blower delay on, the control energizes the indoor
blower.
10. After the 45 seconds second stage warmup period control checks the thermostat
input. If W1 and W2 is present control enters normal operating loop where all
inputs are continuously checked.
F. First Stage and Second Stage Removed Simultaneously:
1. Upon a loss of W1 and W2 the gas valve is de-energized.
2. Upon a loss of flame, each inducer will complete a 5 second postpurge and the
indoor blower will complete a 90 second delay off.
3. Control in the stand by mode with solid red LED.
The integrated control is a four-ignition system.
After a total of four cycles without sensing main burner flame, the system goes into a
100% lockout mode. After one hour, the ignition control repeats the prepurge and igni-
tion cycles for 4 tries and then go into 100% lockout mode again. It continues this
sequence of cycles and lockout each hour until ignition is successful or power is inter-
rupted. During the lockout mode, neither the ignitor or gas valve will be energized until
the system is reset by turning the thermostat to the "OFF" position or interrupting the
electrical power to the unit for 3 seconds or longer. The induced draft blower and main
burner will shut off when the thermostat is satisfied.
The circulating air blower will start and run on the heating speed if the thermostat fan
switch is in the "ON" position.
The integrated furnace control is equipped with diagnostic LED. The LED is lit continu-
ously when there is power to the control, with or without a call for heat. If the LED is
not lit, there is either no power to the control or there is an internal component failure
within the control, and the control should be replaced.
If the control detects the following failures, the LED will flash on for approximately 1/4
second, then off for 3/4 second for designated failure detections.
1 Flash: Failed to detect flame within the four tries for ignition.
2 Flash: Pressure switch or induced draft blower problem detected.
WARNING
DO NOT ATTEMPT TO MANUALLY LIGHT THIS FURNACE WITH A MATCH OR
ANY OPEN FLAME. ATTEMPTING TO DO SO CAN CAUSE AN EXPLOSION OR
FIRE RESULTING IN PROPERTY DAMAGE, PERSONAL INJURY OR DEATH.
3 Flash: High limit or auxiliary limit open.
4 Flash: Flame sensed and gas valve not energized or flame sensed with no "W" sig-
nal.
5 Flash: Overtemperature switch open.

OPERATING INSTRUCTIONS

This appliance is equipped with integrated furnace control. This device lights the main
burners each time the room thermostat (closes) calls for heat. See operating instruc-
tions on the back of the furnace/controls access panel.
TO START THE FURNACE
1. Set the thermostat to its lowest setting.
2. Turn off all electric power to the appliance.
3. This appliance does not have a pilot. It is equipped with an ignition device which
automatically lights the burner. Do not try to light the burner by hand.
4. Remove control door.
5. Move control knob to the "OFF" position. Turn the knob by hand only, do
not use any kind of tool.
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