Checking Temperature Sensors - Freestyle 80 Manual

®
W
FreeStyle
ALL
32 Troubleshooting
Check flame signal
1. Navigate to Diagnostics/Inputs on the FreeStyle ® control
display (see pages 60 to 64
2.
FreeStyle ® 80, 120 or 155. The flame signal value must be
at least 255 on high fire FreeStyle ® 80, 120 or 155. , reading
signal drops below this level, the FreeStyle ® control will at-
tempt to correct by increasing the blower speed to increase
flame signal.
3.
ignitor cable insulation.
a. See "Inspect ignition electrode," page 103 to remove and
inspect the ignitor.
b.
see page 103.
c.
tory, replace the ignitor.
4.
a. Inspect the vent and air piping.
b. Check combustion values.
c.
ponents (starting on page 103).
d.
necessary, see page 106.
Check control fuse
control or any major components (blower, etc.).
1. Turn OFF power to boiler at external line switch. Then
remove the jacket door.
2. Figure 106 and Figure 107.
3.
b, Figure 107).
4.
a.
b.
as specified. Failure to comply could result in se-
vere personal injury, death or substantial property
damage.

Checking temperature sensors

1. The boiler temperature sensors (flue, outdoor, return water
and supply water) are all resistance-type devices. Figure 108
the sensors must be no more than 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 temperatures (ice
point, room temperature and sea level boiling point). For
ice point and boiling point, insert the sensor in water at that
temperature. Use an ohmmeter to read resistance value.
Part number 550-142-850/0716
M -
OUNT GAS FIRED WATER BOILER
(continued)
FreeStyle ®
Figure 106 or Item
—
Boiler Manual
Figure 106
Fuse located on rear of circuit board
-
-
-
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
corresponding temperature on the FreeStyle® control display.
The temperature should be close to the value corresponding
to the input resistance.
Figure 108
Temp Temp
Sensor ohms
(°F)
Min Max
32 31530 33480
40 25792 27388
-
50 19258 20450
60 15218 16160
70 11577 12293
80 8891 9441
90 7185 7629
b
Temp
Sensor ohms
(°F) (°F)
Min Max
100 5608 5954 170
110 4590 4874 180
120 3636 3860 190
130 3011 3197 200
140 2417 2567 212
150 1954 2074 -
160 1644 1746 -
a
Sensor ohms
Min Max
1344 1428
1143 1213
945 1003
810 860
657 697
- -
- -
83