Testing the sensor wiring, Testing the control wiring – tekmar 400 House Control Installation User Manual
Page 9
© 2013
400_D - 09/13
9 of 32
A good quality test meter capable of measuring up to 5,000
kΩ (1 kΩ = 1000 Ω) is required to measure the sensor
resistance. In addition to this, the actual temperature must
be measured with either a good quality digital thermometer,
or if a thermometer is not available, a second sensor can
be placed alongside the one to be tested and the readings
compared.
First measure the temperature using the thermometer and
then measure the resistance of the sensor at the control.
The wires from the sensor must not be connected to the
control while the test is performed. Using the chart below,
estimate the temperature measured by the sensor. The
sensor and thermometer readings should be close. If the
test meter reads a very high resistance, there may be a
broken wire, a poor wiring connection or a defective sensor.
If the resistance is very low, the wiring may be shorted,
there may be moisture in the sensor or the sensor may
be defective. To test for a defective sensor, measure the
resistance directly at the sensor location.
Do not apply voltage to a sensor at any time as damage
to the sensor may result.
Testing the Sensor Wiring
Temperature
Resistance
Temperature
Resistance
Temperature
Resistance
Temperature
Resistance
°F
°C
°F
°C
°F
°C
°F
°C
-50
-46
490,813
20
-7
46,218
90
32
7,334
160
71
1,689
-45
-43
405,710
25
-4
39,913
95
35
6,532
165
74
1,538
-40
-40
336,606
30
-1
34,558
100
38
5,828
170
77
1,403
-35
-37
280,279
35
2
29,996
105
41
5,210
175
79
1,281
-30
-34
234,196
40
4
26,099
110
43
4,665
180
82
1,172
-25
-32
196,358
45
7
22,763
115
46
4,184
185
85
1,073
-20
-29
165,180
50
10
19,900
120
49
3,760
190
88
983
-15
-26
139,400
55
13
17,436
125
52
3,383
195
91
903
-10
-23
118,018
60
16
15,311
130
54
3,050
200
93
829
-5
-21
100,221
65
18
13,474
135
57
2,754
205
96
763
0
-18
85,362
70
21
11,883
140
60
2,490
210
99
703
5
-15
72,918
75
24
10,501
145
63
2,255
215
102
648
10
-12
62,465
80
27
9,299
150
66
2,045
220
104
598
15
-9
53,658
85
29
8,250
155
68
1,857
225
107
553
Testing the Control Wiring
Testing the Power
-----------------------------
-----------------------------
If the control display does not turn on, check the Input
Power wiring terminals using an electrical multimeter. The
voltage should measure between 21.6 to 26.4 V (ac). If the
voltage is below this range, measure the line voltage side
of the transformer. The voltage should measure between
103.5 to 126.5 V (ac).
Testing the Thermostats ----------------------
----------------------
If the thermostat display turns on, this indicates that the
thermostat is operating correctly and there are no electrical
issues. In the event that the display is off, or the display is
cycling on and off, follow this procedure.
1. Remove the tN2 wires from the thermostat.
2. Use an electrical meter to measure DC voltage between
the tN2 terminals.
If the DC voltage is 0 V (dc) for 20 seconds, then there is
an open or short circuit in the tN2 wires. If the DC voltage
is 0 V (dc) for 10 seconds and then is 23 to 24 V (dc) for 5
seconds, this indicates the wiring is correct.
3. Connect the thermostat to the tN2 wires from a zone
on a House Control, Wiring Center, or Zone Manager.
4. If the thermostat display is off, or is cycling on and off,
move the thermostat to the next available zone on the
House Control, Wiring Center, or Zone Manager.
If the thermostat display remains permanently on, there
may be a fault with the previously tried zone on the House
Control, Wiring Center, or Zone Manager.
If the thermostat display continues to be off, or is cycling
on and off, there may be a fault on the thermostat.
If a fault is suspected, contact your tekmar sales
representative for assistance.
User Test --------------------------------------
--------------------------------------
The User Test is found in the Toolbox menu of the control.
Press the Menu button to access the Toolbox Menu. Press
the Item button to locate the User Test.
Start the test sequence by going to the User Test item and
pressing the ‘Up’ arrow button.
Pause the test sequence by pressing the Item button. To
advance to the next step, press the Item button again.
If the test sequence is paused for more than five minutes,
the control exits the entire test routine and returns to normal
operation.
To advance to a particular step, repeatedly press and
release the Item button to display the appropriate device.
User Test Sequence
Step 1 Zone 1 turns on for 10 seconds.
Step 2 Zone 2 turns on for 10 seconds.
Step 3 Zone 3 turns on for 10 seconds.
Step 4 Zone 4 turns on for 10 seconds.
Step 5 The DHW pump turns on for 10 seconds.
Step 6 The boiler system pump turns on for 10
seconds.
Step 7 During the boiler test step, zone relays 1 through
4 turn on, and the boil system pump turns on.