>One thing about our heater--and it's been this way from the start--is that
>when the heater turns off (either because the thermostat tells it the
>interior is warm enough, or the heater is manually turned off) *both* the
>"flame" and the blower fan turn off immediately.  This strikes me as wrong,
>as I would have thought that the fan should run for a bit (with "flame"
>off) to cool the heater down.  As it is, if the fan is turned on manually
>(at the heater control panel), hot air blasts out for a good 30 seconds to
>a minute before blowing only cool air.

This is exactly how mine works as well though sometimes the fan comes back on
and blows for a while after being off for a minute or two. It's certainly
not as
efficient as it could be, but I think this is how it's supposed to work.
The newer
models have a more intelligent fan control that varies the fan speed according
to how much heat is being produced.

>Recently, it has been turning itself off with increasing frequency.  The
>panel will still indicate that the system is on, but no fan, no heat.  If
>one turns the fan on (i.e., "fan" not "heat") manually, hot air will come
>out if the system turned itself off only a short time before.   If I try
>this immediately after a spontaneous shut down *very* hot air comes out.

Is your thermostat working? When the heater spontaneously shuts down
can you get it to come back on by adjusting the thermostat? You say that
the panel will still indicate that the system is on--are you talking about
the red light that indicates the rocker switch is in the "on" position or
the green light that indicates that the burner is on?

>But I'm just guessing, since I don't have a wiring diagram.  And even if I
>were right, I'm not about to get in there messing with it without a...
>well... wiring diagram.

The only wiring diagram that came with my unit was a simple diagram
indicating how to connect the thermostat and power supply. I can get you
a copy if you want but I doubt it will be of much help. There is no
information included on how things are wired internally.

-Mark McCulley