Part 3 - Replacing The Thermocouple - Norcold N300.3 Manual

not use a pin or wire to poke into the orifice tube. You can fill up a small drinking glass with
alcohol and allow the burner orifice to soak for several hours if there is any build-up of soot or
carbon. To make sure the orifice is not plugged, try holding your fingers over the three air inlet
holes and blowing into the brass fitting while holding the extended portion of the orifice tube in
the alcohol. You should see bubbles coming out of the gas outlet slits. If not, things are still
plugged up. Photo #10 below shows the cleaned burner orifice tube ready to re-install in the
burner box.
Photo #10
Once the burner orifice assembly is attached, then reattach the gas line fittings using two
wrenches. These are flare nuts and compression fittings and no pipe dope or Teflon tape is
needed.
There are no positional adjustments to the burner orifice and there are no provisions for adjusting
the size of the orifice or air mixture. Once you go through the troubleshooting steps again,
everything should work just perfectly. If a yellow flame continues to appear after cleaning the
burner orifice, then the air mixture is still not correct which means something is wrong with the
mechanical set-up of the burner orifice and the only remedy is to purchase a replacement burner
orifice.
If everything checks out and the propane lights on first try and stays lit, then pat yourself on the
back for doing a good job. You just saved about $100 to $200 in charges and you have the peace
of mind knowing that you did a complete and thorough job.
If you are still have problems keeping the flame lit and you know for sure that the burner orifice
is clean along with the burner box , then the thermocouple may need replacement.

Part 3 - Replacing the Thermocouple

If all burner parts have been cleaned and properly re-assembled, and the burner lights but still
will not stay lit, then it is likely that you have a bad thermocouple. This unit cannot be repaired,
and must be replaced.
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