Answer Neal, This is often referred to as a "mili amp" circuit, so you'll need a multimeter than can read mili amps "MA" on your meter dial. You'll need to have the pilot lit and the thermocoupler disconnected from the safety valve, then check the mili amps from the solder cap in the center of the coupling to the capillary tube casing. No reading( infinite resistance) would indicate a faulty coupler, Thanks and Good Luck Read More... Answered by AppliancePartsPros.com | Friday, January 6, 2012