Rheem 96v series Installation Instructions Manual page 114

TABLE 20 (continued)
R96V FAULT CODES WITH DESCRIPTIONS AND SOLUTIONS
STATUS: This is a critical fault. The furnace will not operate in gas heat modes but all other modes (e.g. cooling) should
function if present simultaneously with a heating call (e.g. defrost call in dual-fuel mode).
DESCRIPTION: This fault indicates that the low pressure switch is open when the inducer is energized at high speed. The
switch must close after the inducer is energized and before the ignition sequence can begin. The switch is ignored except in
heating modes.
EXPECTED OPERATION: (1) DISPLAYED BEFORE HEAT IS ESTABLISHED: The IBM (Indoor Blower Motor) will not be
energized. The fault code will not be displayed until the IDM (Induced Draft Motor) has been energized for a minimum of ten
seconds. The IDM will remain energized at the high speed (high speed is default pre-purge speed) for a period of five minutes
after the beginning of the pre-purge attempt. After five minutes, the IDM is de-energized and second attempt at pre-purge is
made (as long as the heat call is still present). This cycle is repeated indefinately until either the pressure switch closes or the
heat call is lost. (2) DISPLAYED AFTER HEAT IS ESTABLISHED - If this fault is displayed after heat is established, the gas
valve will be de-energized, the IBM will be energized (if not already energized) at the correct heat speed (determined by the
firing rate required by the thermostat) and the IDM will remain energized at high speed. The IBM will complete a 90 second
blower off-delay and the IDM will complete a 20 second post-purge (at high speed). After these delays, a new attempt at ignition
will be made provided the call for heat is still present.
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CAUSE:
(1) Blockage or improper termination in either the inlet or exhaust vents.
(2) The flue vent length and/or number of elbows exceeds the maximum number specified.
(3) Faulty or disconnected inducer.
(4) Faulty control board (inducer relay).
(5) Loose or faulty wiring.
(6) Disconnected, blocked, split or cut pressure switch hoses.
(7) Wind gusts (sporadic).
(8) Faulty pressure switch.
SOLUTION:
(1) Check the vent system for blockage and proper termination and repair as necessary.
(2) Check the specification sheets and/or installation instructions. Remove excess venting.
(3) Repair or replace inducer and/or inducer wiring and/or electrical connections.
(4) Replace control board.
(5) Check wiring and connections. Replace and/or repair as necessary.
(6) Replace hoses as necessary.
(7) Insure proper termination and determine if high altitude kit may be necessary (see item 4)
(8) Replace the pressure switch.
STATUS: This is a critical fault. The furnace will not operate in gas heat modes but all other modes (e.g. cooling) should
function if present simultaneously with a heating call (e.g. defrost call in dual-fuel mode).
DESCRIPTION: This fault indicates that the low pressure switch is open when the inducer is energized at low speed. Since
the furnace only ignites at high fire, this condition should never be seen except after the blower on delay period of the ignition
cycle and only after the furnace attempt to switch to low stage heating. The switch is ignored except in heating modes.
EXPECTED OPERATION: This fault is displayed only after heat is established and switched to low fire with the IBM (Indoor
Blower Motor) energized at low speed. When this fault is displayed the gas valve will be de-energized, the IBM will remain
energized at the low heat speed and the IDM (Induced Draft Motor) will remain energized at the low speed. The IBM will
complete the user-selected blower off-delay (at low speed) and the IDM will complete a 20 second post-purge (at low speed).
After these delays, a new attempt at ignition will be made provided the call for heat is still present.
CAUSE:
(1) Blockage or improper termination in either the inlet or exhaust vents.
(2) The flue vent length and/or number of elbows exceeds the maximum number specified.
(3) Faulty or disconnected inducer.
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(4) Faulty control board (inducer relay).
(5) High altitude kit not installed in areas of high elevation.
(6) Loose or faulty wiring.
(7) Disconnected, blocked, split or cut pressure switch hoses.
(8) Wind gusts (sporadic).
(9) Faulty pressure switch.
SOLUTION:
(1) Check the vent system for blockage and proper termination and repair as necessary.
(2) Check the specification sheets and/or installation instructions. Remove excess venting.
(3) Repair or replace inducer and/or inducer wiring and/or electrical connections.
(4) Replace control board.
(5) Check elevation of the installation and consult the specifications for the furnace to determine if a high altitude kit is needed.
Install proper kit as necessary.
(6) Check wiring and connections. Replace and/or repair as necessary.
(7) Replace hoses as necessary.
(8) Insure proper termination and determine if high altitude kit may be necessary (see item 4)
(9) Replace the pressure switch.
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LOW PRESSURE SWITCH OPEN, INDUCER ON HIGH SPEED
LOW PRESSURE SWITCH OPEN, INDUCER ON LOW SPEED