58MEB, 58HDV, and the 58MTB

58MEB Performance Boost 90

58HDV Performance 95

58MTB Performance 93

all three of these gas furnaces are Carrier's Performance series. Carrier has good description of the various features of these mdls on their website and I suggest you do some research. see link below.

IMO

Here is a link that might be useful: Carrier Gas Furnaces

I have reviewed the Carrier website extensively.

My question was "what are the differences between these types of blowers and what are the pros and cons of each". This information is not provided on the Carrier website that I can see.

Any opinions?

chamberry

var speed motors have been around many years., even in the HVAC industry. however about 10 yrs ago, they began to make their impact especially in residential furnaces and air handlers. GE has been the primary supplier of these motors to the industry.

depending on the set-up required by the specific HVAC mfg, these VS motors have a slow rampup of about 50% speed lasting about three minutes, then 80% lasting about five minutes, and full rampup until stat is satisfied with a short rampdown period.

the benefits of var speed as marketed by the various HVAC brands are as follows:

1.much cheaper to operate than a standard conventional blower motor

2. improved dehumidification when air handler or furnace is operating in AC mode

3. much quieter than a conventional motor.

4.more even temperature constancy in one's home especially when running fan "on" setting.

5. better filtration of air which improves air quality in one's home

6.while there are exceptions, you need the VS motors to reach the effiency numbers on the high end AC and HP condensers.

these motors have proven to be very reliable;however they are expensive to replace if not under warranty.these blower motors are used in the two/three stage gas furnaces as well as air handlers.

there are other energy efficient motors that are not var speed. and then you have the conventional non VS blower motors that have been the workhorse in the industry for many years.

now to these furnaces- 58MEB, 58HDV, and the 58MTB

58MEB Performance Boost 90
does not qualify for the tax credit, has an energy efficient motor but not VS, sgl stg heat

58HDV Performance 95
selected mdls qualify for the tax credit, VS blower motor, two stg heat

58MTB Performance 93
does not qualify for the tax credit, conventional blower motor, two stg heat

I suggest you look at each of these models on Carrier's website and read the key features section,the product specs section, and the consumer brochure found under the support documents section. also look at Carrier's furnace comparison page.

see link below.
IMO

Here is a link that might be useful: Carrier Furnace Comparison

Thanks

Good outline of info above by tiger. However, one thing I recently discovered is that the 58HDV is not 95% efficient if its in the standard upflow position (which most are). If it's installed horizontally or converted to a downflow setup, only then is it 95% AFUE. Not sure how that would affect the tax credit rating however, since the furnace is purchased as a convertible model (meaning it can be installed in any configuration). Just wanted to point that out, however I do not think it would affect your tax credit eligibility.

Variable speed does have advantages when set up properly to do what it can do. If you have very poor ductwork, however, won't see its true benefits, and could cause more noise. In most cases they do provide some improvement in comfort and energy savings.

Thanks RyanHughes,

My installation is horizontal.

I still question the difference between a VS blower and an ECM blower. Contractors are telling me they are virtually the same. Virtually doe not mean exactly, so there must be some difference.

tigerdunes,

The MEB does qualify for the tax credit in any Carrier AC or HP configuration except the Infinity series, see AHRI cert # 3382191 for example. I am herewith dropping the MTB from consideration.

Which raises the rhetorical question, "Does the government have any idea what they are doing? The most efficient AC and HP units in the industry, (i.e., the Infinity Series from Carrier combined with any gas furnace) do not qualify for the "Energy Efficiency Improvements Tax Credit", while less efficient units do.