YORK INTERNATIONAL
41
FORM 150.40-NM25
SINGLE CIRCUIT UNITS
PROBLEM
CAUSE
SOLUTION
F11 Fault Code
1. Check LWT Cutout Point on Panel.
1. Adjust if necessary, and restart unit.
Low Water
2. Defective LWT or RWT sensor.
2. Check according to following table (use
Temperature Shutdown
(Assure the sensor is properly installed
digital volt meter)* Replace if necessary.
in the bottom of the well with a
generous amount of heat conductive
compound.)
LWT: J20-1 to J20-3 RWT: J21-1 to J21-3
Low Compressor Oil
1. Low Oil Charge
1. Oil level should be visible in either
Level (Particularly on
sight glass at all times. Add YORK
Start-Up.)
“C” oil if necessary.
2. Excessive Flood back of Liquid
2. Adjust Thermal Expansion Valve (TXV)
Refrigerant
or Replace Power Element. Check TXV
Bulb Location. Should be located on
suction line at least 8"-10" from nearest
elbow. Bulb should be at 4 o’clock or
8 o’clock position, have good contact
with suction line & be well insulated
from surrounding air.
Crankcase Heater won’t
1. Open in 115VAC wiring to heater
1. Check wiring
Energize (should energize
2. Defective Heater
2. Replace Heater
anytime unit is “OFF”)
3. Auxiliary contacts of Compressor
3. Replace Contactor
(Min. Current draw =
Motor Contactor defective.
2 amps)
Compressor won’t load
1. Suction Pressure 105 PSIG (723 kPaG)
1. Excessive load. Check OPERATING
(solenoid valve de-ener-
(System #1 or 95 PSIG (654.5 kPaG)
LIMITATIONS on page 3. Allow
gizes to load compres-
(System #2)
unit to operate until suction pressure
sor)
drops to 95 PSIG (654.5 kPaG)
2. Discharge Pressure 390 PSIG (2687
2. Check OPERATING LIMITATIONS
kPaG) (System #1) or 380 PSIG
on page 3. Will reload @ 330 PSIG
(2618 kPaG) (System #2)
(227.4 kPaG)
3. Demand not great enough
3. OK
4. Defective Loading Solenoid
4. Replace Compressor Loading Solenoid
5. Faulty Wiring to Loading Solenoid
5. Check Wiring
6. Defective Water Temp. Sensor
6. Replace appropriate Sensor (LWT or
RWT) (See chart under F11 Fault Code)
7. Defective Evaporator Transducer
7. Replace Transducer
8. Relay Output Board defective
8. Replace Relay Output Board (Contact
the local YORK service representative)
9. Defective Micro Board
9. Replace Micro Board (Contact the
local YORK service representative)
Lack of Cooling Effect
1. Fouled Evaporator Surface
1. Contact the local YORK service
representative.
2. Faulty Compr. Suction and/or
2. Contact the local YORK service
Discharge Valves
representative.
Temp. °F
Volt. -(DC)
Temp. °F
Volt. -(DC)
30.9 (-0.5°C)
1.67
50.8 (10.5°C)
2.64
33.6 (0.9°C)
1.79
53.0 (11.7°C)
2.76
36.3 (2.2°C)
1.91
55.1 (12.8°C)
2.89
38.9 (3.8°C)
2.03
57.2 (14.0°C)
3.01
41.4 (5.2°C)
2.15
59.3 (15.2°C)
3.13
43.9 (6.7°C)
2.28
61.3 (16.3°C)
3.25
46.3 (8.0°C)
2.40
63.2 (17.3°C)
3.37
48.6 (9.2°C)
2.52
*Check voltage on Combo Board
