Well, as part of the electrical "check-up" I have been doing I took amp readings at various times on various circuits and have been balancing them out between phases to offer a more balanced load to the electrical... You could tell it was originally done based on the original design, but with the rec-room changes and other things being changed throughout the years it wasn't kept up and re-balanced until I did it...

Well, part of that discovery was finding out the furnace blower (which we run 24/7/365 for air quality) was sucking down 11amps continuously. In looking at things I noticed the motor was original from 1989 and was rated at 9.6 amps. It is also a shaded-pole design that is amazingly inefficient (best source I could find said the most efficient shaded-pole designs could achieve 32% efficiency, with most falling into a 28-30% range). They are so inefficient that today nothing bigger than 1/6hp is ever made shaded-pole. This is a 1/3hp, 1050rpm, 4 speed 48-frame blower motor. In looking up a replacement, AOSmith (now Century motor) makes a drop-in PSC motor with an internal capacitor. It is rated at 5.7amps with a 6.0amp max draw, 4-speeds, etc, with a 60-65% efficiency (found conflicting sources for that one). So I had one shipped, pulled out the old blower and after a short time modifying gear puller arms and coming up with a set of shims to use as grab arms, I pulled the blower wheel off the original motor, got it all apart, cleaned it all up, and got it all back together.

The result is much stronger air coming out of the registers, and it is only drawing 5.0-5.1 amps while running (that reading was taken at the panel 15 minutes after it was running, I will have to recheck it tomorrow). So I am saving about $70-80/mo already with the new motor compared to the old one.

I also considered a ECM motor replacement for ultimate efficiency, especially considering they make a really nice one (the Evergreen IM) that would be a drop-in, but alas I already had the direct-model replacement on the way by the time I saw it. Since that uses a control-signal from the thermostat controls to control the motor speed, it sparked an idea. The way my current setup is done is that when you let the blower auto-control by the furnace it runs at high-speed for cooling, medium-hi for heating and if you set the fan manually on it runs at high all the time (regardless of other settings). Well, I don't think for air circulation off of heat or cooling mode I need to run the blower at max speed, so I am building a circuit to manage the speeds. I will set it with a rotary switch to select what speed I want for air circulation (probably will be low or medium-low), and it will provide overrides based on the heating or cooling mode being activated. If cooling mode is active it will override the rotary switch and run it at high all the time for maximum air circulation. If heating is active it will use the rotary selection for circulation, but once heating is commanded it will shut off the blower all together and allow the furnace to control the blower for proper startup and running. That way I alleviate the problem I had in the past in regards to backdrafting down the flue (since with the blower off it won't be creating a suction in the area), and it will allow the plenum to come up to full temp and then turn on the blower the way the furnace was meant to operate (which will optimize perfomance and longevity). All around it takes care of all the issues I have, as well as save me the most in regards to running the blower at the proper speeds that are needed all the time.

Oh, I am handling the cooling season/heating season changes by a "state" that is set when either the cooling mode or heating mode is commanded. Even in the event of a power failure, upon restart whichever mode is commanded first will set the current state. In spring/fall when you can have a flip-flop of states I don't think it is a big deal for the blower to run at varied speeds until it settles in, one way or the other.