Armstrong (by Lennox) Enhanced 95v furnace with variable speed fan motor

[ebarry]

I am looking at buying this furnace but the installer is giving me bad vibes about getting one with a variable speed fan motor. He says I may be getting into problems with a new untested technology. His concern is the number of wires coming off the motor. Does anyone have any info on this motor? It is a GE ECM. Also the furnace unit is priced at $2214., does that sound right?

Thanks for any help available.

[hvacdrd]

The ECM is not exactly new, Carrier & Bryant have been using it at least 15-20 years. The newer version ECM2 is awsome and you will love it. The motor ramps up slowly at start up instead of banging on. I suspect the installer doesn't like it because he doesn't understand it. 

As far as cost, it is a $450-500 upgrade at dealer cost. Customers that have one will not go back to the old PSC style.

Take a look at the GE ECM website for more info than I can provide.

[ebarry]

Thanks for the vote of confidence re the motor. The $2214. is for the Armstrong Enhanced 95V furnace WITH the variable speed motor. This furnace has an AFUE efficiency rating of 94.5% which should show us a lot of savings over the 75% efficient furnace we have now. Installed cost is about $3400 and we'll get $1,000 rebate from our government as part of the GHG reduction effort.

[applianceman18007260692]

The only thing I would be concerned about is if the motor is variable speed ,what is it that varys trhe speed? must be some fancy smancy lighting prone computerized board that changes the voltage? If so How much is the replacement board? Stuff like that crosses my mind when I look at buying newer equipment for myself.

[dkpd1581]

I am glad that you are getting such a high efficiency furnace.  It is rather amusing that your installer is worried about the number of wires to the motor.  To say that the motors are untested technology reinforces the fact that he is not comfortable with these motors.  Currently these motors go to version 2.5 (5 generations getting better and more reliable as we go).

Closer to the truth may be that he is not familiar with them and troubleshooting them.  Furthermore, he is probably worried about installing the item and having to stand behind a year's worth of warranty. 

I have to admit as a service tech, it is sometimes hard to get decent tech support on some of these motors from the local reps/suppliers.  I spent 3 days trying to find a "smart guy" at the local Carrier dealer; however, I perservered and got my answer.

These motors are sensitive to voltage spikes, typically the inverter module bolted to the bottom of the motor gets damaged.  The motor itself rarely goes bad and boards are pretty rugged.  A good tech may be able to look and see that the $10 Radio Shack thryector is blown on the module and know to replace it.  He may also just be a parts changer and order the module for $300+.

New mandates for higher efficiency and more eco friendly refrigerants are forcing the market to adapt.  Some of the growing pain is the technician having to keep up with newer technologies.  This involves taking the time to keep current and purchasing newer diagnostic tools.  Translated - the techs may try to avoid the new stuff and give you advice similar to what you recieved. 

No worries though.  Get your cool unit, enjoy the efficiency and comfort, and the business will catch up - albeit kicking and screaming.  Remember, pain is the patient's problem and the industry will get over it and you will be able to get service.