Weil-McLain SVF 1500 Manual page 101

SVF
™
Series 1
Commercial Condensing Gas-Fired Water Boiler — Boiler Manual
Troubleshooting
Make sure to determine the causes of outages. Do not leave the boiler operating without a complete diagnosis.
Figure 100
Sensor resistance value
Sensor resistances for Flue temperature,
Outdoor, Boiler in & out, Return, and System sensors
Sensor ohms
Temp
(°F)
Min Max
32 34265 37871
40 27834 30764
50 21630 23907
60 16944 18727
13372 14780
70
80 10629 11747
8504 9399
90
100 6847 7568
5545 6129
110
Figure 101
Control display toggles when in lockout, with screen flashing red to gray
Part number 550-100-250/0819
(continued)
Sensor ohms
Temp
(°F)
Min Max
120 4517 4992
130 3698 4088
140 3043 3364
150 2517 2782
2091 2311
160
170 1744 1928
1461 1615
180
190 1229 1359
1038 1147
200
boiling point, insert the sensor in water at that temperature. Use
an ohmmeter to read resistance value.
4. To check whether the control module is correctly sensing tem-
perature, you can use a resistance decade box. Connect the decade
box temporarily in place of a sensor and read the corresponding
temperature on the Control display. The temperature should be
close to the value corresponding to the input resistance.
Control fault indications
1. The Control provides diagnostic information for both automatic
reset conditions and manual reset conditions. See Figure 63,
page 72 for information available on the Control display.
2. Figure 101 shows the screen behavior during an automatic or
manual reset condition. The table below the display illustration
lists manual reset conditions and how to reset from them.
3. Figure 102, page 102 lists conditions that will cause the control to
display a constant red screen. The boiler will automatically restart
if the condition self-corrects or the technician uses the Control's
manual reset screens to reset.
101