Sensor Strip And Sensor Strip Replacement Kit - Rheem 310 Series Service Instructions Manual

Component Test 4

Sensor Strip and Sensor Strip Replacement Kit

Unplug the sensor strip plug from the controller and using a multimeter set on the
resistance (kilo-ohms) scale, measure between the pins of the sensor strip plug.
Alternatively, use the Sensor Strip Tester described on page 39, Rheem part
number 891012.
Note: The sensor strip plug sockets are quite small. Fine Probe Adapters (available from
Rheem Spare Parts, part number WH0020082) can be utilised as probe extensions.
Alternatively small pins may be used, however ensure good contact is made when testing.
There are six individual sensors contained along the length of the sensor strip (sensors S0
– S5) therefore there are six individual tests to be performed. As the resistance of each
sensor will change according to its temperature, the resistance measurements for each
sensor will need to be checked against the Sensor Strip Temperature / Resistance Table
below. For this reason it is best to empty the tank of hot water and then measure the cold
water temperature at the T&PR, so a known temperature datum can be used to assess all
sensors which should then in turn all have a similar resistance value when tested.
Sensor Test Points
S0: Between Pins 5 and 1
S1: Between Pins 3 and 2
S2: Between Pins 5 and 4
S3: Between Pins 5 and 6
S4: Between Pins 7 and 8
S5: Between Pins 9 and 10
Sensor Strip Temperature / Resistance Table
The table below sets out the resistance of the sensors for a given water or air temperature.
R (kΩ)
T (°C) T (°C)
-10 44.70 10
-9 42.65 11
-8 40.72 12
-7 38.88 13
-6 37.14 14
-5 35.38 15
-4 33.80 16
-3 32.30 17
-2 30.87 18
-1 29.51 19
0 28.22 20
1 26.98 21
2 25.81 22
3 24.69 23
4 23.63 24
5 22.65 25
6 21.70 26
7 20.80 27
8 19.94 28
9 19.12 29
TM025: 310 Series Heat Pump Service Instructions
Rev AF: Issued March 2016
This document is stored and maintained electronically by
SENSOR STRIP PLUG PIN
CONFIGURATION
R (kΩ) R (kΩ)
T (°C)
18.30 30 8.267
17.55 31 7.960
16.83 32 7.666
16.15 33 7.385
15.50 34 7.115
14.87 35 6.870
14.27 36 6.628
13.71 37 6.396
13.17 38 6.173
12.65 39 5.960
12.11 40 5.740
11.64 41 5.543
11.19 42 5.354
10.76 43 5.173
10.35 44 4.999
10.00 45 4.818
9.618 46 4.652
9.254 47 4.494
8.906 48 4.342
8.573 49 4.195
Technical Support. All printed copies are deemed uncontrolled.
TESTING THE SENSOR STRIP
R (kΩ)
T (°C) T (°C)
50 4.063 70
51 3.928 71
52 3.798 72
53 3.673 73
54 3.552 74
55 3.442 75
56 3.331 76
57 3.224 77
58 3.120 78
59 3.021 79
60 2.929 80
61 2.837 81
62 2.749 82
63 2.663 83
64 2.581 84
65 2.503 85
66 2.427 86
67 2.353 87
68 2.283 88
69 2.214 89
8.49
TEST 4
R (kΩ)
2.147
2.084
2.023
1.964
1.907
1.850
1.797
1.746
1.697
1.649
1.599
1.553
1.509
1.467
1.426
1.388
1.349
1.312
1.277
1.242
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