In line...

"kevins_news" wrote in message
news
My house (and furnace) is now 1.5 years old. Brand new construction
1.5 years ago. Since it is our first house we didn't think about
things like putting in a different furnace. We picked the colors,
cabinets, hardwood, countertops, and just let the builder put in all
their default models for things like doors, windows, furnace, etc.

I assume i have what people call a Natural Gas Mid Efficiency furnace.
Since all the high efficiency ones advertize multiple fan speeds
(which mine doesn't have) i would assume mine isn't one of those.


It probably a multi speed blower, even if it is a builder's grade furnace.
US Energy code says the lowest efficiency furncae out there is 78%. I
haven't seen a 78 in a few years as most are 80%.


First some questions:

Are the energy savings from HE furnaces in the electircy needed to run
the fan? Or the efficiency of burning the gas (ie uses less gas to
make same amount of heat)?

Some is in the blower efficiency, but not all. Mostly it has to do with the
efficiency of the burning gas.

And what is the purpose of multiple fan speeds? Is this so you can leave
the fan on a
low setting constantly to keep air circulation happening? Other than
allowing the air filter to be constantly working, what is the purpose
of this?

Furnaces are set up for a specific temprature rise. The multiple speeds are
for setting this 'Delta T.' Some of the equiptment has a setting for
continous circulation for better air filtration, but probably not yours.

Would it be worthwhile to replace mine with high efficiency even
though it (and the building) is so new. two story, 1700 square feet
townhouse. On the main floor only two walls are exposed to the
outside. The other two walls are shared with neighbouring townhouses.
Our entire 2nd story is exposed though since neither neighbour has a
2nd floor.

If you asked me this question while I was at your house, I'd stifle a grin
and say a resounding "NO!" You'll never make the return on your investment,
in my opinion.


We are pretty energy conscious so i bet the furnace is already
running less than the average household. I'd hate to spend $3000
(Canadian) on a furnace and find out i save only $100 a year in
gas/electiricty.


Good for you.

Are there any theoretical numbers? A TV commercial says "It will save
the average household X dollars a month" but with no indication of
what "average" is. Maybe someone has a study where a mid efficiency
furnace runs for X hours a day to heat the house, and a HE furnace
would only run for Y hours. I could use that ratio to estimate
something.

Don't beleive everything you hear. I'd like to think those commercials are
for the people that have furnaces a lot older than yours.

Any thoughs appreciated.

You're welcome.