>> >> Basically, the thermostat controls the burner and the limit switches
>> >> control the blower based on the internal temperature. You want about
>> >> 90dF low and 110 high. It lets the burner pre-heat so you don't get
>> >> a cold blast, and runs the fan after the burner has shut off so you
>> >> don't waste heat up the chimney.
>> >
> Ummmm, yes you are missing something - read the first sentence. They're
> talking about the limit switches in the furnace itself.
I guess I'm still asking "why should they matter"?
The jobs they were describing the limit switches as doing are done on
mine by the thermostat... as in "delaying fan start until a settable
period after ignition" and "continuing fan use until a period after
flame off".
Now, the digital one does it by time and not temperature but....
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