ridgeback wrote:

Help. I started up my good old furnace after a) checking for water b)
blowing out the fuel lines c) cleaning the strainer d) breaking down
and cleaning the pump e) cleaning out the blower blades f) lubricating
the motor and g) replacing the burner nozzle with the right size, with
the electrodes adjusted for the right angle. What I get is a silky
smooth start that runs the timer limit and shuts off. Big pretty
flame, steady oil stream. What tells it to stop? The blower never
comes on but when I run it manually it makes no difference. Same cut
off, same time.


If the burner operates too long without the blower coming on, it could
be shutting down due to the high temperature triggering the limit switch.
It could be a dirty or malfunctioning cad cell.
Turn on the blower manually & see if it still shuts down.
Check the heat anticipator on the thermostat & set it between .2 & .4 amps.
There is no way to troubleshoot from here!
http://www.udarrell.com/oil_furnace_heating.html
- udarrell

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