hype, bunk, or for real?

Dave Yates (GrandPAH)

<a href="http://fmsiusa.com/pages/Airco.html">http://fmsiusa.com/pages/Airco.html</a>



Tough for me to believe the stated 20% to 30% energy reduction. Given that induction motors draw high amps on start-ups, wouldn't cycling the compressor tend to cancel out the energy reductions?

Techman

All three

It is really a bunch of bunk and don't beleave the hype. Even Scroll's draw more at start-up,and recips even more.I am happy to finally realize that the freon is pushed into the evap coil and stored there for future use. It's all making much more sense now!!!!!!!!!!!!!! But ,I will eat my word's if shown that it works! Two calendar year pay-back? Or two YEARS of running time?

Ironman

Doesn't Make Sense to Me

In addition to the reasons already stated, I see at least two more:



1. Over 90% of the wear on a compressor takes place at start up. So I've always been told. Correct me if I'm wrong.



2. The compressor is not operating efficiently for up to the first five minutes after starting because  it has to get the refrigerant to the right places, temps, etc. This is especially true with a heat pump or any unit that has an accumulator; it's just not doing what it should until the refrigeration process settles out.



So yes, I'm very skeptical too.

meplumber

Bunk

I get the same feeling with this that I got with the Acadia Heat Pump.



That turned out to be crap too.

Dave Yates (GrandPAH)

Acadia

Off the thread topic, but yours is the first negative Acadia comment I've read. What was the experience?

Eugene_Silberstein

I'm not convinced either

Constant starting and stopping definitely takes its toll on the compressor and uses a lot more energy than adjusting compressor speed (and refrigerant mass flow rate) according to the load on the system.



I guess that using some type of "smart" control is better than no control, but it seems that the jury (at least mine) is still out.

Tom Blackwell_2

Bunk also

This is a simple "duty cycler" device that turns the compressor on and off during the unit's normal on cycle. These devices were popular among shysters during the Jimmy Carter years. Destroyed a lot of equipment. Even saw the aftermath of having one applied to a 500 ton centrifugal chiller-broke the slot insulators in the motor rotor. Of course, the individual responsible for destroying a $150,000 piece of equipment had arranged to have no liability. Unfortunately we will see more of this as energy costs rise. To put it in simple terms, energy efficiency is the practice of moving BTU's from point a to point b using the least amount of energy. Nothing magic about this.

don_9

on and off

Yea and we all know what one get from a simple duty cycler,not enough cool calls.lol.Almost like the little energy box they are installing to start taking out equipment when the wattage use goes up,.the bad thing is it take the system off line when you need it most.