Fault Code 22
SETUP ERROR—This fault indicates that setup switches SW-1 or SW-6 are ON when they should be OFF. The
following combinations will cause the fault:
• Thermostat call with SW-1 ON.
• Thermostat call with SW-6 ON.
• SW-1 and SW-6 both ON together.
STEP ACTION YES NO GO TO
1. Turn power off and remove blower access panel. — — 2
2.
Make sure thermostat is NOT calling for heating or cooling. Disconnect all thermostat terminal leads
to make sure.
—— 3
3. Is setup switch SW-1 in ON position? 4 6 —
4. Put setup switch SW-1 in OFF position. — — 5
5. Go to page number indicated in Index for CLEANUP AND START-UP INSTRUCTIONS. — — INDEX
6. Is setup switch SW-6 in ON position? 7 8 —
7. Put setup switch SW-6 in OFF position. — — 5
8. Replace furnace control board. —— 5
Fault Code 23
INVALID BLOWER AIRFLOW SELECTION—This fault indicates improper A/C or CF switch setting. The -14
units can deliver sufficient airflow for 1-1/2 to 3-1/2 tons A/C and 600 to 1400 CFM for continuous fan. The -20
unit can deliver sufficient airflow for 2 to 5 tons A/C and 800 to 2000 CFM for continuous fan. If fault code is
flashing, unit still operates, but it defaults to closest allowable airflow.
NOTE: Boards with date codes of 9506 or later will flash fault code and set continuous fan airflow to same airflow as A/C if continuous fan
is adjusted to a higher airflow than A/C setting.
STEP ACTION YES NO GO TO
1. Turn power off and remove blower access panel. — — 2
2. Are air conditioning select switches A/C set properly? (See Table 2.) 5 3 —
3. Set air conditioning select switches A/C for proper tonnage as required by condensing unit. — — 4
4. Go to page number indicated in Index for CLEANUP AND START-UP INSTRUCTIONS. — — INDEX
5. Are continuous fan select switches CF set properly? (See Table 3.) 7 6 —
6.
Set continuous fan select switches CF for desired airflow. This setting should normally be set to DE-
FAULT position unless a 2-speed AC/HP is part of system. Use Table 4 for reference on 2-speed
AC/HP airflow requirements.
—— 4
7.
Are continuous fan select switches CF set to a higher airflow than air conditioning select switches
A/C? (See Tables 2 and 3.)
68 —
8. Is furnace a 100 size? 11 9 —
9.
The problem is in the A/C or CF selection circuit. The maximum cooling or continuous fan airflow for
this unit will be delivered.
—— 10
10.
Jiggle A/C and CF switches back and forth. If fault code continues to flash, replace furnace control
board.
—— 4
11.
The problem is in the A/C or CF selection circuit. The minimum cooling or continuous fan airflow for
this unit will be delivered.
—— 12
12.
Jiggle A/C and CF switches back and forth. If fault code continues to flash, replace furnace control
board.
—— 4
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