Rheem 871018, Service Instructions Manual, Page: 29 / 77

TM031 Integrity 18, 20, 24, 26L Service Instructions REV: B
D.O.I: February 2008
This document is stored and maintained electronically by
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29
Diagnostic Test Points
Refer to wiring diagram, page 5, for connector and wiring positions.
Test
Point
Measuring Point
Normal Condition Items Under Test
Connector
Wire Nº
& colour
1 A R1
– R2
AC 85V
– 120V
Main Power
2 B W8
– W12
50 kilo-ohms
– 500 kilo-ohms
Overheat Limiter
3 B
BR9
– BL10
DC 2V
– 5V(Pulse)
*1
Water Flow Sensor pulse signal
More than 1310 pulse/min
R11
– BL10
DC 7V
– 15V
Water Flow Sensor
4 K
B4
– W6
DC 120V
– 170V
Fan Motor
R3
– B4
DC 11V
– 19V
Y1
– B4
DC 4V
– 10V(Pulse)
*1
Fan Motor is pulse signal
More than 4800 pulse/min
5 B Y6
– BL7
@ 20ºC
– 10.3 kilo-ohms
Water Inlet Thermistor
@ 40ºC
– 4.9 kilo-ohms
6 B W5
– BL7
@ 20ºC
– 10.3 kilo-ohms
Heat Exchanger Thermistor
@ 40ºC
– 4.9 kilo-ohms
7 B R4
– BL7
@ 20ºC
– 10.3 kilo-ohms
Hot Water Outlet Thermistor
@ 40ºC
– 4.9 kilo-ohms
8 B B3
– BL7
@ 25ºC
– 5.0 kilo-ohms
Ambient Air Thermistor
@ 5ºC
– 12.7 kilo-ohms
9 J
R1
– Earth
AC 2V
– 20V
*2
Flame Sensor detecting flame W3
– Earth
AC 2V
– 20V
*2
B2 - Earth AC 2V
– 20V
*2
10 B R1
– BL2
DC 1.5V
– 8.0V
Proportional Gas Flow Regulating
42 ohms
– 97 ohms
11 L Y9
– BL10
DC 70V
– 110V
Gas Inlet Solenoid Valve
0.8 kilo-ohms
– 2.2 kilo-ohms
12 L R2
– R8
AC 85V
– 120V
Igniter
13 L R3
– BL10
DC 70V
– 110V
Solenoid Valve 1
0.8 kilo-ohms
– 2.2 kilo-ohms
14 L W4
– BL10
DC 70V
– 110V
Solenoid Valve 2
0.8 kilo-ohms
– 2.2 kilo-ohms
15 L B5
– BL10
DC 70V
– 110V
Solenoid Valve 3
0.8 kilo-ohms
– 2.2 kilo-ohms
16 J
R1
– Earth
AC 2V
– 20V
*2
Flame Sensor not detecting flame. W3 - Earth AC 2V
– 20V
*2
17 J B2 - Earth AC 2V
– 20V
*2
18 H
W2
– BL8
DC 8V
– 16V
Water Volume Control Motor
position switch
R7
– BL8
DC 8V
– 16V
GR6
– BL8
Less than DC 1V (Limiter off)
DC 4V
– 6V (Limiter on)
19 L O6
– O12
DC 70
– 110V
0.6 kilo-ohms
– 2.8 kilo-ohms
Water Bypass Solenoid (models
with -B or -C suffix in model number
only e.g. 871024-B)
NOTES:
*1:
Approximate reading measured by digital multimeter on DC range.
*2: Approximate reading measured by digital multimeter on AC range.