I recently had some A/C service done, and the tech recommended that I leave
the furnace blower running constantly, letting the heat and cooling come on
as needed. The theory is that is would "even out" the air temperatures
throughout the house (I have a 2-story house with basement, dual zone
system). Makes sense to me, but wanted to know what the smart folks in this
Last year my tech told me the same thing in the winter I do not have a
heating problem but in the
summer its harder to cool evenly. My down stairs was comfortable and
upstairs too warm. I have vents
on the wall floor level. I purchased angled plastic to shoot the cold air
up and re adjusted all the vents
to have less cold air down and keep the vents upstairs open all the way.
The ac runs a little longer but
its more comfortable all over. PLUS I KEEP THE FAN RUNNING 24/7 it helps a
lot try and
see what you think.
It will keep you more even and clean your air better , but figure the
cost. I pay 0.12 KWH my fan pulls apx 400 watts or 9600 a day , at
0.12 thats 1.152 a day or 34.56 a month. Well my entire electric bill
last month was 15. I think I like the savings of 350 a year, but you
may enjoy the comfort Also fan motors only last just so long.
That's 9600 watt-hours or 9.6 kWh per day.
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I've been here 13 years and just last month replaced a fan motor that had
been running 24/7.
Of course the motor was the original from the '60's, so the life expectancy
of a 24/7 motor is somewhere between 13 and 40 years.
Sure run it 24x7 to save the motor , and heat - cool more evenly or
just do what is smart . get a better thermostat or adjust your
anticipator for less swing , or get the proper equipment with a DC
motor . Or get a better tech.
My last motor was original, 40 yrs old and consumed apx 550 watts.
The furnace never runs more than 8 hrs a day in winter at -10f and avg
over the whole summer 1 hr a day. So say in winter for 6 months I
would be adding 16 hrs and in summer for 6 months 23 hrs running. So
in winter I would add 8.8 kwh daily, 264 kwh mo. 1584 kwh - 6 mo x
0.12 kwh for an increase $ 190.00 . In summer 12.65 kwh daily
379.5 mo. 2277 - 6 mo x .012 kwh = $273.24 or $463.24 a year or
9264.80 over 20 yrs or an axp 40000.00 -50000.00 with compounded
interest . Sure everybodys run time is different but many of you have
much bigger unefficient motors pulling Double this amount or more.
So how many motors and doughnuts can you buy for $ 40 - 50000.00
thousand thousand thousand. And for what , better air flow?
Go buy a new furnace with a DC motor that consumes 50% less and a
Running constant fan is not going to hurt your equipment, but if the ducting is
leaking to the exterior; it will amplify any losses you may already have. As air
leaves the building through leaks in the ducting, it is replaced by air
infiltrating through crawl space, attic etc.
Also run it at lower speed if wanted. My electric power costs 8
cents/KWh fixed for next 4 years. Monthly average usage is 1200KWh.
High efficieency blower motors are DC driven which has higher efficiency.
On Wednesday, February 5, 2014 8:44:01 PM UTC-5, Batjo wrote:
I'd add to that, it's very dependent on how the system is
actually installed. If all the ducting runs only in heated parts
of the building, then the potential for heat loss is little.
If the furnace is in an unheated basement or even worse, an attic,
some ducts run through outside walls, etc, then it's going to be
a losing proposition for sure. Plus, I don't see the need. All
the houses I've lived in with furnaces it was comfortable
with the fan just running when the furnace was on.
In my previous house, I ran mine all the time during the summer to de-ice
the a/c coils between cooling cycles. Compared to the power used by the
compressor, the cost of running the fan was nothing.
It was a new Clayton trailer home. Clayton used ducts that were too small
and airflow was inadequate as far as I was concerned. Clayton said it was
adequate. Trailer homes are built to minimum specs. I agree it shouldn't
have been like that, but it was. A local heating contractor told me the only
solution would have been to put in larger ductwork to get adequate airflow.
Clayton, by the way, is bottom of the line. I learned a lot when I bought
that home. Now I live in a site built home. No more trailer homes for me.
I also would like to hear what others have to say about this.I have
been keeping my AC in the fan position but keep it on auto during the
heating season. I did some un-scientific testing after having my
Central AC installed a few years ago.I found that the AC compressor
ran only a little more than half as often if the FAN was allowed to
run all of the time. Also the house comfort level seems better with
the air constantly moving.
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