Whirlpool W10301482B Tech Sheet page 6

Table of Contents

Advertisement

TECH SHEET - DO NOT DISCARD
TEST #4 Heater
This test is performed when one of the following
situations occur:
Dryer does not heat
Heat will not shut off
Display flashes L2
This test checks the components making up the heating
circuit. The following items are part of this system:
– Harness/connection
– Centrifugal switch
– Heater relay
– Exhaust thermistor
– Thermal cut-off
– Machine control
electronics. See ESD
– Inlet thermistor/
information, page 1.
high limit thermostat
– User interface
– Heat element
assembly
assembly
Dryer does not heat or display flashes L2:
Locate the components using figure 2, page 4; and
figure 9, below.
Thermal Cut-Off
Inlet Thermistor/
High Limit
Thermostat
Heater
Element
Thermal Fuse
Figure 9. Thermal components, viewed from
front.
1. Unplug dryer or disconnect power.
2. Remove the front panel and drum assembly to
access the thermal components. See Removing
the Front Panel/Drum Assembly, page 9.
3. Using an ohmmeter and referring to the
appropriate wiring diagram (see pages 11 and
12), measure the resistance across the high limit
thermostat.
➔ If an open circuit is not detected, go to step 5.
➔ If an open circuit is detected, go to step 4.
4. Visually check the wire connections to the
thermal cut-off and the high limit thermostat.
If connections look good, check for continuity
across each of these components. Replace both
the thermal cut-off and the inlet thermistor/high
limit thermostat assembly if either the thermal
cut-off or the high limit thermostat is electrically
open.
F
O
R
S
E
R
V
I
C
E
T
E
C
H
N
I
C
5. Measure the resistance between the red wires
at the heater.
➔ If an open circuit is not detected, go to
step 7.
➔ If an open circuit is detected, go to step 6.
6. Visually check the wire connections to the heater.
If the connections look good, replace the heater
assembly.
7. Visually check connections at the machine control
electronics. If the connections look good, and an
open circuit was not previously detected at the
heater, remove the P4 connector, then measure
the resistance between P4-3 (red wire) and P4-6
(red wire) at the connector. See figure 16, page 9
for connector location; and Accessing &
Removing the Electronic Assemblies, page 9.
➔ If 5–15 kΩ are measured, replace the machine
control electronics.
➔ If the resistance is less than 1 kΩ, replace the
exhaust thermistor.
Heat will not shut off:
1. Unplug dryer or disconnect power.
2. Access the machine control electronics.
See Accessing & Removing the Electronic
Assemblies, page 9. Remove the P4 connector.
See figure 16, page 9 for connector location; then
measure the resistance between P4-3 (red wire)
Exhaust
Thermistor
and P4-6 (red wire) at the connector.
➔ If 5–15 kΩ are measured, replace the machine
control electronics.
➔ If the resistance is greater than 20 kΩ, replace
the exhaust thermistor.
TEST #4a Thermistors
EXHAUST THERMISTOR
The machine control electronics monitors the
exhaust temperature using the exhaust thermistor,
and cycles the heater relay on and off to maintain
the desired temperature.
Begin with an empty dryer and a clean lint screen.
1. Plug in dryer or reconnect power.
2. Start the Timed Dry cycle.
3. If after 60 seconds,
display and the dryer shuts off, the thermistor or
wire harness is either open or shorted.
➔ Unplug dryer or disconnect power.
➔ Check wire connections at the machine control
electronics and thermistor. See Accessing &
Removing the Electronic Assemblies, page 9;
and for thermistor location, figure 9.
I
A
N
S '
U
S
E
O
N
L
Y
4. If
TEMPERATURE
*
5. If the exhaust temperature is not within specified
F :22
or
F :23
flashes in the
INLET THERMISTOR
The machine control electronics monitors the inlet
temperature using an inlet thermistor that is part of
the inlet thermistor/high limit thermostat assembly.
1. Activate the diagnostic test mode. See procedure
2. If
➔ If wire connections are OK, check the exhaust
thermistor resistance per step 5.
F :22
or
F :23
does not flash in the display,
the connections to the thermistor are good.
Therefore, check the exhaust temperature value
at any or all of the temperature levels in question,
using the Timed Dry cycle, and the following
process:
Hold a glass bulb thermometer capable of reading
from 90° to 180°F (32° to 82°C) in the center of
the exhaust outlet. The correct exhaust
temperatures are as follows:
EXHAUST TEMPERATURES
HEAT TURNS OFF*
SETTING
°F (°C)
High
155°±5° (68°±3°)
Medium
140°±5° (60°±3°)
Low
125°±5° (52°±3°)
Extra Low
105°±5° (41°±3°)
The measured overshoot using the glass bulb
thermometer in the exhaust outlet can be 30°F
(17°C) higher.
limits, or you have come here from step 3, unplug
dryer or disconnect power. Remove the P4
connector, then measure the resistance between
P4-3 (red wire) and P4-6 (red wire) at the
connector. See figure 16, page 9 for connector
location; and Accessing & Removing the Electronic
Assemblies, page 9.
➔ If the resistance is OK, check P4-3 and P4-6
to machine ground.
➔ If resistance is greater than 0 (zero), replace
wiring harness.
NOTE: All thermistor resistance measurements
must be made while dryer is disconnected from
power.
The following table gives temperatures and ranges
for the associated thermistor resistance values.
EXHAUST THERMISTOR RESISTANCE
TEMP.
RES.
TEMP.
°F (°C)
°F (°C)
50° (10°)
19.0–22.0
80° (27°)
60° (16°)
14.8–16.8
90° (32°)
70° (21°)
11.5–13.5 100° (38°)
➔ If the thermistor resistance does not agree
with table, replace the exhaust thermistor.
➔ If the thermistor resistance checks agree
with the measurements in the table, replace
the machine control electronics.
on page 1.
F :24 F :25
or
is a displayed error in the
diagnostic test mode, the thermistor or wire
harness is either open or shorted.
P
A
R
T
N
O
.
W10301482B
PAGE 6
HEAT TURNS ON
°F (°C)
10°–15° (6°–8°)
below the
heat turn off
temperature
RES.
8.5–10.5
6.8–8.8
5.0–7.0

Hide quick links:

Advertisement

Table of Contents
loading

Table of Contents