One of the GE Weathertron Model 3AAT80B1A1 thermostats in our home is
doing its thing and if the temperature setting is increased a few
degrees above ambient the auxillary heaters come on OK to supplement the
heat pump's output.

But the blue indicator lamp has stopped lighting in that condition.

I suspect it's just a "burned out bulb". The thermostat is old enough so
I'd doubt that the indicators are LEDs.

Before I attack it, can someone tell me if replacement lamps are
available and easily screwed or snapped in or will I have to figure out
what bulb to get and use my electronic repair skills to solder it in.

Thanks guys,

Jeff
--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
The speed of light is 1.8*10^12 furlongs per fortnight.