On Feb 10, 7:27*am, wrote:
On Feb 10, 2:30*am, wrote:





On Feb 9, 10:35*pm, wrote:

Hi

I know nothing about furnaces but something about the way myfurnace
works doesnt makes sense to me and I was wondering if someone could
give me an explanation...

I have a Carrier Weathermaker 8000 58WAVfurnace. It blows air
continuously. From visual inspection it looks like it draws air from
the basement. It cycles between warm and cool air. The problem is
where I live in the winter it gets extremely cold(can get as cold as
minus 40 degrees). The house is very old and the basement is very
cold. *So thefurnacecycles between very warm and very cold air which
is very uncomfortable and I can't imagine it being very efficient. Is
this a normal setup for afurnace? This is my 1st home and Ive only
lived here for 1 winter so I know very little about this stuff. I
remember my parentsfurnacedidnt blow air continously. It only blew
air on the warm cycle. That seems to make much more sense to me than
cycling between very cold and warm air.

Thanks in advance for any insight

Dennis

After doing some digging around it would seem that some furnaces have
two modes...Fan "On" and "Auto". Theres no mention of it in the
furnacemanual but Im starting to suspect myfurnacehas this option
that can be set from the thermostat. The problem is my thermostat is
one of those old kind with the mercury tube in it. No fan settings.
Maybe the previous owner upgraded thefurnacebut not the thermostat.
There's only two wires travelling from thefurnaceto the thermostat
so even if I had a newer thermostat with a fan setting, there arent an
fan wires to connect it too. Is it possible myfurnaceis stuck in
"ON" mode?- Hide quoted text -

- Show quoted text -

That' what it sounds like. * Normally, there is a switch setting on
the thermostat to set the blower to either auto or on. *Since your
thermostat only has two wires and no such switch, it sounds like thefurnaceitself is wired for the blower to be on all the time.
Personally, I would not want it set up that way. * Most are set for
the blower to come on only when heat is being delivered. *With an
olderfurnaceand conventional blower, this is going to consume a lot
of electricity. *Newer high efficiency blowers it would use a lot
less, but still will add up run 24/7.

Regarding sucking air from the basement, what makes you think it's set
up that way? * There should be return ducts going to the living space
that bring that air to the suction side of the blower.- Hide quoted text -

- Show quoted text -

So it turns out I was on the right track. There's terminals in the
furnace for fan operation that weren't being used(my thermostat is
only 2 wire) I learned of these terminals from an online post about a
different brand of furnace but figured it was a standard setup. I
wired up the fan terminals to a manual switch and now my fan only
comes on during the warm cycle!! So Im pretty happy about that.

As for air being sucked in from the basement. Theres a return duct in
the basement that eventually leads to the filter and then blower
chamber. This makes great sense for house cooling in the summer but
makes no sense in the winter. To me it would make more sense if there
was a 2nd return duct upstairs where the air is warmer. With that
setup one could close the downstairs duct in the winter and open the
upstairs one. In the summer you reverse the scenario....oh well Im
just learning and at least I dont have a "cold cycle" anymore!

Thanks everyone for your help!
Dennis