Checking Temperature Sensors - Freestyle FS-80 NG Instruction Manual

W
FreeStyle
ALL
32 Troubleshooting
Check flame signal
1. Navigate to Diagnostics/Inputs on the FreeStyle ™
control display (see pages 56 to 60
structions.
2.
a FreeStyle ™ 80 or 120, and 255 on high fire, reading at
signal drops below this level, the FreeStyle ™ control
will attempt to correct by increasing the blower speed
to increase flame signal.
3.
aged ignitor cable insulation.
a. See "Inspect ignition electrode," page 99 to remove
and inspect the ignitor.
b.
structed, see page 99.
c.
wiring is in good condition, and ground continuity
4.
a. Inspect the vent and air piping.
b. Check combustion values.
c.
boiler components (starting on page 99).
d. Clean the heat exchanger as described in this manual
page 102.
Check control fuse
control or any major components (blower,
FreeStyle ™ control or other components
1. Turn OFF power to boiler at external line switch. Then
remove the jacket door.
2. Figure 103 and Figure 104.
3.
b, Figure 104).
4.
a.
b.
except as specified. Failure to comply could
result in severe personal injury, death or sub-
stantial property damage.

Checking temperature sensors

1. The boiler temperature sensors (flue, outdoor, return
water and supply water) are all resistance-type devices.
Figure 105
various temperatures. For dual sensors, the temperature
10 °F. (Supply outlet 200 sensor).
2. Use the resistance values at 32°F, 60°F, 70°F and 212°F
to measure the sensor resistance at known tempera-
tures (ice point, room temperature and sea level boil-
ing point). For ice point and boiling point, insert the
sensor in water at that temperature. Use an ohmmeter
to read resistance value.
Part number 550-142-850/0115
M -
OUNT GAS FIRED WATER BOILER
(continued)
Figure 103 or Item
—
Boiler Manual
Figure 103
-
Fuse located on rear of circuit board
-
-
Figure 104
Installer/homeowner note,
DHW mode but NOT in
Central Heating mode.
3. To check whether the FreeStyle™ control is correctly sensing
temperature, you can use a resistance decade box. Connect the
responding temperature on the FreeStyle™ control display. The
temperature should be close to the value corresponding to the
input resistance.
Figure 105
Temp
Sensor ohms
(°F)
Min Max
32 34265 37871
40 27834 30764
50 21630 23907
60 16944 18727
70 13372 14780
80 10629 11747
90 8504 9399
b
Temp Temp
Sensor ohms
(°F) (°F)
Min Max
100 6847 7568 170
110 5545 6129 180
120 4517 4992 190
130 3698 4088 200
140 3043 3364 212
150 2517 2782 -
160 2091 2311 -
a
-
Sensor ohms
Min Max
1744 1928
1461 1615
1229 1359
1038 1147
1038 1147
- -
- -
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