Trying to learn something about the state of the art in gas, forced hot air
furnaces before calling
contractors in for quotes. Present furnace in house is about 25 yrs. old.
Two questions for now:
Do these new units use a pilot light that is always on ?
The variable speed blowers I've heard about: are the models that
incorporate them (usually) truly variable speed, or just a discrete two, or
perhaps three, speeds ?