I've had a Heil updraft furnace installed in my little brick
bungalow since 03-06. Standard-looking rig.

Sequence of ops looks like:

Tstat calls for heat
inducer motor runs for a bit
igniter heats up
gas valve opens, burners fire
igniter turns off
blower kicks in

What can y'all tell me about the inducer motor? When is it
supposed to run? Not run? What does it really do?

Furnaces didn't used to have inducer motors. When and why did
we get inducer motors? Was it because of redesign of the
heat exchangers?

In the context of design, are inducer motors really needed in modern furnaces?
Or are they another bell-and-whistle that mostly just generates service
/parts revenue?

Thx,
Puddin'

"Blues starts to rolling ... stops at my front do'.
I'm gonna change my way of living ... won't have to worry no mo'."
- from "Blues Before Sunrise", Leroy Carr, maybe 1934

Puddin' Man wrote:
I've had a Heil updraft furnace installed in my little brick
bungalow since 03-06. Standard-looking rig.

Sequence of ops looks like:

Tstat calls for heat
inducer motor runs for a bit
igniter heats up
gas valve opens, burners fire
igniter turns off
blower kicks in

What can y'all tell me about the inducer motor? When is it
supposed to run? Not run? What does it really do?

Furnaces didn't used to have inducer motors. When and why did
we get inducer motors? Was it because of redesign of the
heat exchangers?

In the context of design, are inducer motors really needed in modern furnaces?
Or are they another bell-and-whistle that mostly just generates service
/parts revenue?

Thx,
Puddin'

"Blues starts to rolling ... stops at my front do'.
I'm gonna change my way of living ... won't have to worry no mo'."
- from "Blues Before Sunrise", Leroy Carr, maybe 1934


From what I've read the inducer motor really is necessary. The heat
exchanger for the modern furnace is so convoluted and has so much drag
that depending on mere hot air to start and continue the draft is not
possible. Old furnaces could and did depend on the "hot air rises"
principle to establish their draft but that only goes so far and not
much air is going to wind up going through those little soda straw-sized
passages in a modern heat exchanger unless it gets a bit of a goose.

--
John McGaw
[Knoxville, TN, USA]
http://johnmcgaw.com

"Puddin' Man" wrote in message
...

I've had a Heil updraft furnace installed in my little brick
bungalow since 03-06. Standard-looking rig.

Sequence of ops looks like:

Tstat calls for heat
inducer motor runs for a bit
igniter heats up
gas valve opens, burners fire
igniter turns off
blower kicks in

What can y'all tell me about the inducer motor? When is it
supposed to run? Not run? What does it really do?

Furnaces didn't used to have inducer motors. When and why did
we get inducer motors? Was it because of redesign of the
heat exchangers?

In the context of design, are inducer motors really needed in modern
furnaces?
Or are they another bell-and-whistle that mostly just generates service
/parts revenue?

Thx,
Puddin'

"Blues starts to rolling ... stops at my front do'.
I'm gonna change my way of living ... won't have to worry no mo'."
- from "Blues Before Sunrise", Leroy Carr, maybe 1934

The inducer motor is what provides the draft for the burners. It reduces the
heat loss out the vent which would otherwise be necessary for the draft. It
is a good efficieny and safety improver, though it does add initial and
service cost. It runs at the beginning of the heat cycle to purge any stray
gas from the combustion area, continues to run while the burners are on, and
runs for a short time after the burners go off in order to clear the fumes
from the furnace.

Don Young

try removing it and see if it runs , ;-=)

Puddin' Man wrote:
I've had a Heil updraft furnace installed in my little brick