On Tue, 10 Dec 2013 23:02:10 -0700, Tony Hwang wrote:

Don't worry about lock up timer it only starts when safety issue arises
like over heating triggering over heat limit sensor. This is
kind of thermostat for fixed temp sensing. There are few in there for
different functions/purposes. If you want to reset the lock out timer
just power cycle the furnace,(resetting control board)

Just as an aside, the $279 lockout timer appears to be a normally open
switch, based on these two descriptions:
http://www.furnacepartsource.com/dls015.html
https://acpartsdistributors.com/inde...ducts_id=59920

It is called a "Combustion Safety Control Lockout Timer" (whatever that
is supposed to mean) over here, also sold for $279:
http://www.bestbuyheatingandaircondi...Code=r-lockout

So, it seems to be an expensive normally opened timed switch.

It seems to have a timer of about five minutes.
After five minutes, presumably it closes the SPST switch.
I'm still trying to figure out what it's supposed to do.

It's hooked up *before* the pilot, so, being normally open is
odd.
http://technicalhotandcoldparts.com/...r-control.html