"Steve" fired this volley in
:

I do approximately 5 semester hours a year in
continuing education just to keep up with the new technologies. The
newest super high efficiency systems are serial controlled, with
variable frequency inverter drives and can vary their output capacity
from 40 - 115%. Even the compressors are driven by electronically
commutated, variable speed motors. This technology has only been on
the streets for a year or so in residential split systems. If you
don't have the proper training, you can cause some very expen$ive
problems by something as simple as getting 2 control wires crossed.
BTW... all these classes, and training isn't free, and the customer
pays for *EVERYTHING*.


Yeahbut... that's electronics, not refrigeration technology. Any new
industrial machine you can name has the same new features.

F'instance, the new indoor fan motors pretty much come as 3-phase VFD
units, with the VFD built into the motor case. It's a fine technology,
but it ups the life-cost to the consumer, because many of the motors do
NOT have replacement VFD boards available (especially the low-end GE
motors) -- where if a start/run cap failed on an older technology motor,
it would cost (the tech) pennies to fix.

But that's (again) all electronics. Show me any _substantial_ changes in
refrigeration technology.

LLoyd