Applies to:

Replacing the High Limit Thermocouple

Replacing

To avoid electrical shock or property damage, move the power switch to OFF and disconnect power.

  1. Remove electrical power supplied to the unit.

  2. Lower the control board.

  3. Mark and disconnect the wires from the high limit control located behind the control board mounted to the frame.

  4. Using a 1/2 inch wrench, loosen the compression fitting on the probe.

  5. Slide the fitting nut and the ferrule back to loosen the probe.

  6. Remove the vat bushing from the vat. Replace with the new bushing included with new part. Apply thread sealant and tighten into vat.

  7. Apply thread sealant to the compression fitting. Thread into the vat bushing.

  8. Insert the probe into the compression nut and the ferrule.

  9. Insert the new probe into the compression fitting. Be sure to insert the probe end into the sleeve welded to the burner tube inside of the vat.

  10. Tighten the compression fitting nut.

For additional troubleshooting refer to the JWF Light Code Chart.

Thermoelectric voltage as a function of temperature (°F); reference junctions at 32 °F.

Thermoelectric Voltage in Millivolts
F 0 1 2 3 4 5 6 7 8 9 10
50 0.507 0.535 0.563 0.592 0.620 0.649 0.677 0.705 0.734 0.762 0.791
60 0.791 0.819 0.848 0.876 0.905 0.933 0.962 0.991 1.019 1.048 1.076
70 1.076 1.105 1.134 1.162 1.191 1.220 1.249 1.277 1.306 1.335 1.364
80 1.364 1.364 1.392 1.421 1.450 1.479 1.508 1.566 1.594 1.623 1.652
90 1.652 1.681 1.710 1.739 1.768 1.797 1.826 1.855 1.884 1.913 1.942
100 1.942 1.972 2.001 2.030 2.059 2.088 2.117 2.146 2.175 2.205 2.234
110 2.234 2.263 2.292 2.322 2.351 2.380 2.409 2.439 2.468 2.497 2.527
120 2.527 2.556 2.585 2.615

2.644

 2.673 2.703 2.732 2.762 2.791 2.821
130 2.821 2.850 2.880 2.909 2.938 2.968 2.997 3.027 3.057 3.086 3.116
140 3.116 3.145 3.175 3.204 3.234 3.264 3.293 3.323 3.353 3.382 3.412
150 3.412 3.442 3.471 3.501 3.531 3.560 3.590 3.620 3.650 3.679 3.709
160 3.709 3.739 3.769 3.798 3.828 3.858 3.888 3.918 3.948 3.977 4.007
170 4.007 4.037 4.067 4.097 4.127 4.157 4.187 4.217 4.246 4.276 4.306
180 4.306 4.336 4.366 4.396 4.426 4.456 4.486 4.516 4.546 4.576 4.606
190 4.606 4.636 4.666 4.696 4.726 4.757 4.787 4.817 4.847 4.877 4.907
200 4.907 4.937 4.967 4.997 5.028 5.058 5.088 5.118 5.148 5.178 5.209
210 5.209 5.239 5.269 5.299 5.329 5.360 5.390 5.420 5.450 5.480 5.511
220 5.511 5.571 5.571 5.602 5.632 5.662 5.692 5.723 5.753 5.783 5.814
230 5.814 5.874 5.874 5.905 5.935 5.965 5.996 6.026 6.056 6.087 6.117
240 6.117 6.178 6.178 6.208 6.239 6.269 6.299 6.330 6.360 6.391 6.421
250 6.421 6.452 6.482 6.512 6.543 6.573 6.604 6.634 6.665 6.695 6.726
260 6.726 6.756 6.787 6.817 6.848 6.878 6.909 6.939 6.970 7.000 7.031
270 7.031 7.061 7.092 7.122 7.153 7.184 7.214 7.245 7.275 7.306 7.336
280 7.336 7.367 7.398 7.428 7.459 7.489 7.520 7.550 7.581 7.612 7.642
290 7.642 7.673 7.704 7.734 7.765 7.795 7.826 7.857 7.887 7.918 7.949
300 7.949 7.979 8.010 8.041 8.071 8.102 8.133 8.163 8.194 8.225 8.255
310 8.255 8.286 8.317 8.347 8.378 8.409 8.439 8.470 8.501 8.532 8.562
320 8.562 8.593 8.624 8.654 8.685 8.716 8.747 8.777 8.808 8.839 8.869
330 8.869 8.900 8.931 8.962 8.992 9.023 9.054 9.085 9.115 9.146 9.177
340 9.177 9.208 9.238 9.269 9.300 9.331 9.362 9.392 9.423 9.454 9.485
350 9.485 9.515 9.546 9.577 9.608 9.639 9.669 9.700 9.731 9.762 9.793
360 9.793 9.823 9.854 9.885 9.916 9.947 9.977 10.008 10.039 10.070 10.101
370 10.101 10.131 10.162 10.193 10.224 10.255 10.285 10.316 10.647 10.378 10.409
380 10.409 10.440 10.470 10.501 10.532 10.563 10.594 10.625 10.655 10.686 10.717
390 10.717 10.748 10.779 10.810 10.840 10.871 10.902 10.933 10.964 10.995 11.025
400 11.025 11.056 11.087 11.118 11.149 11.180 11.211 11.241 11.272 11.303 11.334
410 11.334 11.365 11.396 11.426 11.457 11.488 11.519 11.550 11.581 11.612 11.642
420 11.642 11.673 11.704 11.735 11.766 11.797 11.828 11.858 11.889 11.920 11.951
430 11.951 11.982 12.013 12.044 12.074 12.105 12.136 12.167 12.198 12.229 12.260
440 12.260 12.290 12.321 12.352 12.383 12.414 12.445 12.476 12.506 12.537 12.568
450 12.568 12.599 12.630 12.661 12.691 12.722 12.753 12.784 12.815 12.846 12.877
460 12.877 12.907 12.938 12.969 13.000 13.031 13.062 13.093 13.123 13.154 13.185
470 13.185 13.216 13.247 13.278 13.308 13.339 13.370 13.401 13.432 13.463 13.494
480 13.494 13.524 13.555 13.586 13.617 13.648 13.679 13.709 13.740 13.771 13.802
490 13.802 13.833 13.864 13.894 13.925 13.956 13.987 14.018 14.049 14.079 14.110
500 14.110 14.141 14.172 14.203 14.233 14.264 14.295 14.326 14.357 14.388 14.418
510 14.418 14.449 14.480 14.511 14.542 14.573 14.603 14.634 14.665 14.696 14.727
520 14.727 14.757 14.788 14.819 14.850 14.881 14.911 14.942 14.973 15.004 15.035
530 15.035 15.065 15.096 15.127 15.158 15.189 15.219 15.250 15.281 15.312 15.343
540 15.343 15.373 15.404 15.435 15.466 15.496 15.527 15.558 15.589 15.620 15.650
550 15.650 15.681 15.712 15.743 15.773 15.804 15.835 15.866 15.897 15.927 15.958
560 15.958 15.989 16.020 16.050 16.081 16.112 16.143 16.173 16.204 16.235 16.266
570 16.266 16.296 16.327 16.358 16.389 16.419 16.450 16.481 16.512 16.542 16.573
580 16.573 16.604 16.635 16.665 16.696 16.727 16.758 16.788 16.819 16.850 16.881
590 16.881 16.911 16.942 16.973 17.003 17.034 17.065 17.096 17.126 17.157 17.188

Thermoelectric voltage as a function of temperature (°C); reference junctions at 0 °C.

Thermoelectric Voltage in Millivolts
C 0 1 2 3 4 5 6 7 8 9 10
50 2.585 2.638 2.691 2.744 2.797 2.850 2.903 2.956 3.009 3.062 3.116
60 3.116 3.169 3.222 3.275 3.329 3.382 3.436 3.489 3.543 3.596 3.650
70 3.650 3.703 3.757 3.810 3.864 3.918 3.971 4.025 4.079 4.133 4.187
80 4.187 4.240 4.294 4.348 4.402 4.456 4.510 4.564 4.618 4.672 4.726
90 4.726 4.781 4.835 4.889 4.943 4.997 5.052 5.106 5.160 5.215 5.269
100 5.269 5.323 5.378 5.432 5.487 5.541 5.595 5.650 5.705 5.759 5.814
110 5.814 5.868 5.923 5.977 6.032 6.087 6.141 6.196 6.251 6.306 6.360
120 6.360 6.415 6.470 6.525 6.579 6.634 6.689 6.744 6.799 6.854 6.909
130 6.909 6.964 7.019 7.074 7.129 7.184 7.239 7.294 7.349 7.404 7.459
140 7.459 7.514 7.569 7.624 7.679 7.734 7.789 7.844 7.900 7.955 8.010
150 8.010 8.065 8.120 8.175 8.231 8.286 8.341 8.396 8.452 8.507 8.562
160 8.562 8.618 8.673 8.728 8.783 8.839 8.894 8.949 9.005 9.060 9.115
170 9.115 9.171 9.226 9.282 9.337 9.392 9.448 9.503 9.559 9.614 9.669
180 9.669 9.725 9.780 9.836 9.891 9.947 10.002 10.057 10.113 10.168 10.224
190 10.224 10.279 10.335 10.390 10.446 10.501 10.557 10.612 10.668 10.723 10.779
200 10.779 10.834 10.890 10.945 11.001 11.056 11.112 11.167 11.223 11.278 11.334
210 11.334 11.389 11.445 11.501 11.556 11.612 11.667 11.723 11.778 11.834 11.889
220 11.889 11.945 12.000 12.056 12.111 12.167 12.222 12.278 12.334 12.389 12.445
230 12.445 12.500 12.556 12.611 12.667 12.722 12.778 12.833 12.889 12.944 13.000
240 13.000 13.056 13.111 13.167 13.222 13.278 13.333 13.389 13.444 13.500 13.555
250 13.555 13.611 13.666 13.722 13.777 13.833 13.888 13.944 13.999 14.055 14.110
260 14.110 14.166 14.221 14.277 14.332 14.388 14.443 14.499 14.554 14.609 14.665
270 14.665 14.720 14.776 14.831 14.887 14.942 14.998 15.053 15.109 15.164 15.219
280 15.219 15.275 15.330 15.386 15.441 15.496 15.552 15.607 15.663 15.718 15.773
290 15.773 15.829 15.884 15.940 15.995 16.050 16.106 16.161 16.216 16.272 16.327
300 16.327 16.383 16.438 16.493 16.549 16.604 16.659 16.715 16.770 16.825 16.881
310 16.881 16.936 16.991 17.046 17.102 17.157 17.212 17.268 17.323 17.378 17.434
320 17.434 17.489 17.544 17.599 17.655 17.710 17.765 17.820 17.876 17.931 17.986
330 17.986 18.041 18.097 18.152 18.207 18.262 18.318 18.373 18.428 18.483 18.538
340 18.538 18.594 18.649 18.704 18.759 18.814 18.870 18.925 18.980 19.035 19.090
350 19.090 19.146 19.201 19.256 19.311 19.366 19.422 19.477 19.532 19.587 19.642
360 19.642 19.697 19.753 19.808 19.863 19.918 19.973 20.028 20.083 20.139 20.194
370 20.194 20.249 20.304 20.359 20.414 20.469 20.525 20.580 20.635 20.690 20.745
380 20.745 20.800 20.855 20.911 20.966 21.021 21.076 21.131 21.186 21.241 21.297
390 21.297 21.352 21.407 21.462 21.517 21.572 21.627 21.683 21.738 21.793 21.848
400 21.848 21.903 21.958 22.014 22.069 22.124 22.179 22.234 22.289 22.345 22.400
410 22.400 22.455 22.510 22.565 22.620 22.676 22.731 22.786 22.841 22.896 22.952
420 22.952 23.007 23.062 23.117 23.172 23.228 23.283 23.338 23.393 23.449 23.504
430 23.504 23.559 23.614 23.670 23.725 23.780 23.835 23.891 23.946 24.001 24.057
440 24.057 24.112 24.167 24.223 24.278 24.333 24.389 24.444 24.499 24.555 24.610
450 24.610 24.665 24.721 24.776 24.832 24.887 24.943 24.998 25.053 25.109 25.164
460 25.164 25.220 25.275 25.331 25.386 25.442 25.497 25.553 25.608 25.664 25.720
470 25.720 25.775 25.831 25.886 25.942 25.998 26.053 26.109 26.165 26.220 26.276
480 26.276 26.332 26.387 26.443 26.499 26.555 26.610 26.666 26.722 26.778 26.834
490 26.834 26.889 26.945 27.001 27.057 27.113 27.169 27.225 27.281 27.337 27.393
500 27.393 27.449 27.505 27.561 27.617 27.673 27.729 27.785 27.841 27.897 27.953
510 27.953 28.010 28.066 28.122 28.178 28.234 28.291 28.347 28.403 28.460 28.516
520 28.516 28.572 28.629 28.685 28.741 28.798 28.854 28.911 28.967 29.024 29.080
530 29.080 29.137 29.194 29.250 29.307 29.363 29.420 29.477 29.534 29.590 29.647
540 29.647 29.704 29.761 29.818 29.874 29.931 29.988 30.045 30.102 30.159 30.216

Related Content

Replacing the High Limit Control

Replacing the Temperature Probe

Replacing the Gas Valves

Replacing the Gas Valve Solenoid Coil

Replacing the Burner Tubes

Replacing the Blower

Replacing the Vacuum Switch

Replacing the Pilot

Replacing the Pressure Switch

Reference

Error Codes

Specifications

LVG 200 Wiring Diagrams

LVG 200 Plumbing Diagrams