trader_4 wrote:
On Saturday, November 8, 2014 3:54:41 PM UTC-5, wrote:
On Sat, 08 Nov 2014 14:28:14 -0500, "(PeteCresswell)"
wrote:

Per Steve Kraus:
Looking for recommendations for a brand or general type that would be
quieter since this is located right in the middle of living space.

Our NG furnace/AC says "Trane XV80" on the name plate.

It's predecessor was a fifties-era furnace/AC which was quite loud to my
ears... and to the wife's.

The Trane has a variable-speed blower and is located about 20 feet from
where I do most of my computer work. I would call it "quiet" and I'm
kind of neurotic about noise... so it's probably *really* quiet.

Also, the variable-speed blower seems to take less electric. During an
outage, with a little 2KW gennie supplying electric through a
smart/auto-load-shedding cutover panel, there's no problem running
refrigerators, freezers, TV, computers, lights.... and the furnace.
We swirched from a 35+ yr old standard gas furnace to a mid
efficiency furnace with DC variable speed blower. Our gas bill didn't
change a measurable amount, but our electric bill went down. The DC
motor is so much more efficient that the gas furnace had to replace
the heat not made by the motor - increasing the amount of heat needed
by about the same percentage as the efficiency of the burner had
improved...


It would be one hell of a fractional HP motor that generated anywhere
that much heat. It's typically only 1/3 hp, maybe 1/2. I replaced a
27 year old furnace and the gas bill decreased dramatically. Didn't
notice any difference in the electric bill and that's with a variable
speed ECM blower.


Hi,
DC motor is always more efficient. Even my GDO has 140V DC motor, small
in size but pretty powerful.