Table 9 — Quick Test, Thermistor and Potentiometer Check
QUICK
TEST
STEP NO.
NORMAL
DISPLAY
DESCRIPTION
THERMISTOR OR
POTENTIOMETER*
1.4.
1
1 — Thermistor OK
0 — Thermistor Faulty
Leaving Air
Thermistor (T1)
1.5.
1
1 — Thermistor OK
0 — Thermistor Faulty
Entering Air
Thermistor (T2)
1.6.
1
024-030
1 — Resistor OK
0 — Resistor Faulty
034-074
1 — Thermistor OK
0 — Thermistor Faulty
Circuit 1 Condenser Thermistor
(T3) or Resistor
1.7.
1
024-030
1 — Resistor OK
0 — Resistor Faulty
034-074
1 — Thermistor OK
0 — Thermistor Faulty
Circuit 2 Condenser Thermistor
(T4) or Resistor
1.8.
1
1 — Thermistor or Potentiometer OK
0 — Thermistor or Potentiometer Faulty or
Option not used
Accessory Space Temperature Thermistor (T10)
or Accessory Reset Potentiometer (P7)
1.9.
1
1 — Potentiometer OK
0 — Potentiometer Faulty
Supply-Air Set Point
Potentiometer (P1)
2.0.
1
1 — Potentiometer OK
0 — Potentiometer Faulty or Option not used
Accessory Reset Limit
Potentiometer (P3)
2.1.
1
1 — Potentiometer OK
0 — Potentiometer Faulty or Option not used
Accessory Demand Limit
Potentiometer (P4)
2.2.
1
1 — Potentiometer OK
0 — Potentiometer Faulty or Option not used
Minimum Position
Economizer
Potentiometer (P5)
2.3.
1
1 — Potentiometer OK
0 — Potentiometer Faulty or Option not used
Warm-Up Set Point
Potentiometer (P6)
*Potentiometer P2 is not listed since it is not part of the quick test. If on unit start-up a Code 83 is displayed, check potentiometer P2.
Table 10 — Quick Test, Output Relay Check
QUICK
TEST
STEP NO.
NORMAL
DISPLAY
DESCRIPTION
RELAY NUMBER
2.4.
1
1 — Open Economizer or Open Relay if no Economizer
K7
2.5.
1
1 — Close Economizer or Close Relay if no Economizer
K8
2.6.
1
1 — Energize Fan Relay and Heat Relay
K9* and K10
2.7.
1
Energize Stage 1 Condenser Fan(s)
K11
2.8.
1
Energize Stage 2 Condenser Fan(s) — 034-074 Only
K12
2.9.
0 then 1 then 0
Energize Compressor 1†
K1
3.0.
0
Energize Unloader 2 (024-034, 054-074); Not Used (044)
K2
3.1.
0
Energize Unloader 1
K3
3.2.
0 then 1 then 0
Energize Compressor 2†
K5
3.3.
0
Not Used
K6
CR — Control Relay
*K9 (fan relay) will remain on for duration of quick test.
†Compressor will be energized for 10 seconds. Zero indicates open CR; 1 indicates closed CR.
20
