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Scout
 
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Default Hey Seahag...little help in the galley please

"Joe" wrote in message
ups.com...
Have you ever had any problems with a thermocoupler on your force 10?

My broiler keeps shutting down. Maybe just a stuck electromagnet???
Do you know what voltage they are suppose to make so I can check it out
with a meter?


Joe,
If memory serves me correctly, a thermocouple with no load should read about
25 millivolts. If you have the screw-in adapter that allows you to check
voltage while under a load, it should be between 10 and 15 mV. Many years
ago I worked on thermocouple systems, and did a test we called "listening
for thud" Place an inline voltage access adapter in the circuit and test
thermocouple output voltage under a load. While the pilot is operating
normally, blow out the flame. Place a screw driver or other "listening"
device against the gas valve and the other end against your ear. When the
pilot valve closes, you'll hear a "thud", which is the solenoid losing its
ability to hold back the force of the spring (i.e., the pilot gas valve
closes). Thud shouldn't happen above 15-17 millivolts. If it does, and you
have clean and tight electrical connection, replace the valve. If the
voltage is low or below 10 while under a load, replace the thermocouple.
This assumes that the pilot flame is adjusted properly and hitting the tip
(about 1/3 of) the thermocouple.

If you don't have the adapter, but you do have a good millivolt meter, then
see what the voltage output is with the electrical end of the thermocouple
disconnected. It's not as conclusive as testing under a load, but it will
probably tell you what you need to know.

If you don't have a good meter, thermocouples are fairly inexpensive and it
won't hurt to replace it as your test.

Scout