replying to Tony Hwang , BobinDurham wrote:
dragon40 wrote:

Hi,
Main valve is controlled by 24V control voltage, not by thermocouple.
thermocouple's job is to keep the pilot on.


Maybe a thermocouple's....but a thermopile generates the energy to open
the gas valve. Once you turn the valve to pilot and ignite it, the pilot
is on. If the pilot blows out for some reason, the thermopile senses the
loss of heat and shuts the pilot valve down. Which is why if you turn the
pilot on, push the knob in and ignite it....and you don't let the
thermopile heat up enough? The pilot goes out.


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