DIYbanter - View Single Post - Has anyone ever replaced their conventional furnace fan motor with anECM motor?

Some Guy[_2_]

wrote:

My definition of planned obsolescence is a product deliberately
built to only last X years and then require replacement,
when it could have been built for the same cost to last longer.

I would agree with the above definition.

In the case of, say, a furnace, there is a complicating factor that
the owner is not usually the one that makes the decision that the item
needs replacing. He is being coerced into that decision on the advice
of someone who has an interest in selling you a replacement.

In other situations, the complete failure of a product is more clearly
visible to the owner, and he or she can go remove and replace it
without relying on a third party.

But getting back to furnaces,

If 30 years ago you had one part in a furnace who's mtbf was 20 years,
and when that part failed then the most practical recourse was to
replace the furnace, well in some cases you will get 15 years before
failure and in others you will get 25, even 30 years before failure.

Today, if you have 3 or 4 critical parts, each with an MTBF of 20
years, then the odds are higher that the furnace will fail at 10 years
because you have 3 or 4 critical parts and the failure of ANY ONE of
them means the failure of the furnace.

A 20-year warranty on the heat exchanger is meaningless if you will
still have to pay $1000 for labor to replace it, and the contractor or
repair guy is telling you he'll sell you a new furnace for $2000. Is
that a situation that a homeowner wants to face? Will he feel good
about making the decision?

Wouldn't it just be easier to add a few more oz. of stainless steel to
the heat exchanger design and have an exchanger with an mtbf of 50
years?

And besides, with houses better insulated today, you don't need a
million BTU output furnace. With constant (or near constant) run
times, furnaces can put out lower BTU's constantly and are avoiding
hot/cold cycling. Our knowledge of metalurgy and alloys is better
today, the demands on a furnace are less today than they were 30+
years ago. So it's practically criminal that a heat exchanger is only
warranted for 20 years these days.

So, I'd say the fact that today's HVAC systems don't last as long
is a reaction to market expectations and consumer preferences,
not a focus on planned obsolescence.

The furnace that does in the typical new house is not chosen by the
first owner - it's chosen by the builder.

The first owner of a new home, if given the opportunity, is more
likely to pay attention to ANYTHING going into the house's
construction vs any future owner of the house.

It would be nice if there was, or could be, some sort of
communications channel directly between a new home owner and a furnace
manufacturer, such that the home owner knew that he had the option of
paying $500 more for a furnace that would last 35 years vs maybe 20
years, and if the home owner could convey that decision to the home
builder, and if the builder didn't gouge the owner and charge him
$1500 extra for that furnace.

a reaction to market expectations and consumer preferences

In the case of a furnace, the market has no expectations because the
market has such little exposure to or life-experience with the
product. It's hidden down in some dark corner of the house, mostly
unseen.

Look at cars. People become intimately familliar with their cars.
Cars are vastly more complicated, and put to more demanding use than
furnaces. Cars today easily last 15 years - most of that time the car
is no longer under any warranty so repair costs must always make
economic sense vs buying a new car.

What we have in cars is a setup whereby we have a repair
infrastructure (parts stores, independent mechanics, etc) who have an
interest in you keeping and repairing your old car. They have no
interest in you buying a new car every time one of your tires goes
flat. When it comes to furnaces, we don't have that situation. Any
third party who repairs furnaces is also most likely to benefit MORE
by selling you a new furnace. Most likely you won't complain or
question their recommendation because you have a general awareness
that furnaces are important and 10 or 15 years is a long time for
anything mechanical to keep working and furnaces are generally a
mysterious black box to you so you'd better leave it to the "experts"
to tell you what to do.