Hi

I have the Keeprite 075 condensing gas furnace. Only about 10 years old.
Honeywell pro 8000 thermostat. NUGM100EHB1 is the furnace.

My question is what happened all of a sudden yesterday when I think I had a
bit too much humidity in the air, why did the furnace fail?

Now when there is a call for heat on the thermostat, what happens is both
blowers run only. The exhaust blower venting out runs immediately on start
up, the main house blower starts immediately on start up. But no clicking
from the honeywell smart valve, no sparking or ignighting beginning or
trying. Nothing else is happenening. No gas is going through the valve, no
obstructions in either intake or exhaust piping. I just vacuumed everything
out, I changed thermostates to the old one, same thing happens. I suspect
either the motherboard which has no lights to blink to show alarms, or the
gas valve which I had to replace couple years ago, But back then at least
the igniters would light up and shut off immediately, told me it was a gas
valve issue so replaced that and worked. All else looks clean and I smacked
as many relays as I could see, checked all the tubes to see if connections
are ok and seems ok. Even when thermostat is turned off, disconnected, when
I turn the furnace on it only immediately starts up the both blowers and
nothing else, no clicking, no safeties going on and off, no nothing. Anyone
here have a suggestion other than hiring an HVAC contracting firm to come in
and give me estimates? I know a board is about 50 bucks, easy to replace,
gas valve is about 150 easy to replace, what ever sensor should be cheap and
easy to replace. Any suggestions as to what to try next?

Thanks Hams, I know this is off topic, but I have gotten good advice from
this group before and there are no furnace newsgroups of any kind on my
server.
Thanks for any advice or tips or links
73

Tuuk wrote:
Hi

I have the Keeprite 075 condensing gas furnace. Only about 10 years old.
Honeywell pro 8000 thermostat. NUGM100EHB1 is the furnace.
Any suggestions as to what to try next?


Learn to use Google!

On Fri, 16 Dec 2011 18:20:26 -0500, Tuuk wrote:

I have the Keeprite 075 condensing gas furnace. Only about 10 years old.
Honeywell pro 8000 thermostat. NUGM100EHB1 is the furnace.
My question is what happened all of a sudden yesterday when I think I had a
bit too much humidity in the air, why did the furnace fail?

Probably due to your bad karma from posting OT material in usenet ngs.

Hi

Ya, I googled it a lot, found some information but nothing explaining why
the furnace's both fans run immediately with nothing else happening.

Suppose I will try replacing components one by one, I'll go by most replaced
components. I can google that.

I tried jumping the high low switches, the vacuum switch, cleaned out the
chamber, cant really see the ignighter but that is an easy replacement and
might as well after 10 years. I heard they rarely last that long.

Got some excellent advice from this group before, will do it again.






"Allodoxaphobia" wrote in message
g.com...
On Fri, 16 Dec 2011 18:20:26 -0500, Tuuk wrote:

I have the Keeprite 075 condensing gas furnace. Only about 10 years old.
Honeywell pro 8000 thermostat. NUGM100EHB1 is the furnace.
My question is what happened all of a sudden yesterday when I think I had
a
bit too much humidity in the air, why did the furnace fail?

Probably due to your bad karma from posting OT material in usenet ngs.

" Tuuk" wrote in message
...
Hi

I have the Keeprite 075 condensing gas furnace. Only about 10 years old.
Honeywell pro 8000 thermostat. NUGM100EHB1 is the furnace.

My question is what happened all of a sudden yesterday when I think I had
a bit too much humidity in the air, why did the furnace fail?

Now when there is a call for heat on the thermostat, what happens is both
blowers run only. The exhaust blower venting out runs immediately on start
up, the main house blower starts immediately on start up. But no clicking
from the honeywell smart valve, no sparking or ignighting beginning or
trying. Nothing else is happenening. No gas is going through the valve, no
obstructions in either intake or exhaust piping. I just vacuumed
everything out, I changed thermostates to the old one, same thing happens.
I suspect either the motherboard which has no lights to blink to show
alarms, or the gas valve which I had to replace couple years ago, But back
then at least the igniters would light up and shut off immediately, told
me it was a gas valve issue so replaced that and worked. All else looks
clean and I smacked as many relays as I could see, checked all the tubes
to see if connections are ok and seems ok. Even when thermostat is turned
off, disconnected, when I turn the furnace on it only immediately starts
up the both blowers and nothing else, no clicking, no safeties going on
and off, no nothing. Anyone here have a suggestion other than hiring an
HVAC contracting firm to come in and give me estimates? I know a board is
about 50 bucks, easy to replace, gas valve is about 150 easy to replace,
what ever sensor should be cheap and easy to replace. Any suggestions as
to what to try next?

Thanks Hams, I know this is off topic, but I have gotten good advice from
this group before and there are no furnace newsgroups of any kind on my
server.
Thanks for any advice or tips or links
73



When you say no lights to blink - do you mean it has no lights on the board
to do that
or do you mean there are lights on the board but they do not light up.
If the latter, it would certainly seem to be the board, if the former then,
darn, no help there.
Having had a similar problem my first replacement item would be the
motherboard.
Normally the vent blower comes on to purge the system for a few seconds,
followed of
course by the igniter, then the gas valve and after a short warm up the main
blower fan.
As both fans and start at the same time and nothing else is happening I am
thinking
the mother board is at fault.
Like you say, easy to replace and not to expensive and from the sound of the
problem
I would guess that is a good starting place.
I have a spare board and whenever I have a problem I use it for trouble
shooting.
If I replace it and get the same problem, then, I am off in search of what
is really
causing the problem.
As a side note, the earlier problem with the gas valve could have also been
a motherboard.
If the vent blower starts, then the igniter lights and then shuts down
either the motherboard
did not sense igniter heat or it did and then did not send the signal to
open the gas valve.
In your case it worked like it should but the valve did not open. It could
have been a bad
igniter sensing circuit or a bad valve opening relay however. Just something
to keep in mind.
Good luck with your problem.
Not a licensed furnace guy or anything, just have to do it all myself living
as far out in the
boonies of northeast Montana as I do. You learn to do this stuff or freeze
during the winter.


K7SAM

On Fri, 16 Dec 2011 18:20:26 -0500, " Tuuk"
wrote:

Hi

I have the Keeprite 075 condensing gas furnace. Only about 10 years old.
Honeywell pro 8000 thermostat. NUGM100EHB1 is the furnace.

My question is what happened all of a sudden yesterday when I think I had a
bit too much humidity in the air, why did the furnace fail?

Now when there is a call for heat on the thermostat, what happens is both
blowers run only. The exhaust blower venting out runs immediately on start
up, the main house blower starts immediately on start up. But no clicking
from the honeywell smart valve, no sparking or ignighting beginning or
trying. Nothing else is happenening. No gas is going through the valve, no
obstructions in either intake or exhaust piping. I just vacuumed everything
out, I changed thermostates to the old one, same thing happens. I suspect
either the motherboard which has no lights to blink to show alarms, or the
gas valve which I had to replace couple years ago, But back then at least
the igniters would light up and shut off immediately, told me it was a gas
valve issue so replaced that and worked. All else looks clean and I smacked
as many relays as I could see, checked all the tubes to see if connections
are ok and seems ok. Even when thermostat is turned off, disconnected, when
I turn the furnace on it only immediately starts up the both blowers and
nothing else, no clicking, no safeties going on and off, no nothing. Anyone
here have a suggestion other than hiring an HVAC contracting firm to come in
and give me estimates? I know a board is about 50 bucks, easy to replace,
gas valve is about 150 easy to replace, what ever sensor should be cheap and
easy to replace. Any suggestions as to what to try next?

Thanks Hams, I know this is off topic, but I have gotten good advice from
this group before and there are no furnace newsgroups of any kind on my
server.
Thanks for any advice or tips or links
73



Check the air intake and exhaust output on the furnace.

If either is clogged, the furnace will start up then shut down.

Also -- how does your system dispose of condensate? Is there a
condensate pump? If it's not working, the system will start up then
shut down when it sense the condensate pump is not working.

When working projects without prior knowledge or experience I try to
use the following approach:
Log observations and my actions on paper
Do what is easy
Do what is cheap
Clean it
Take pictures before disassembly
Determine how it is supposed to work... this is where it gets serious!

On Fri, 16 Dec 2011 18:20:26 -0500, " Tuuk"
wrote:

Hi

I have the Keeprite 075 condensing gas furnace. Only about 10 years old.
Honeywell pro 8000 thermostat. NUGM100EHB1 is the furnace.

My question is what happened all of a sudden yesterday when I think I had a
bit too much humidity in the air, why did the furnace fail?

Now when there is a call for heat on the thermostat, what happens is both
blowers run only. The exhaust blower venting out runs immediately on start
up, the main house blower starts immediately on start up. But no clicking
from the honeywell smart valve, no sparking or ignighting beginning or
trying. Nothing else is happenening. No gas is going through the valve, no
obstructions in either intake or exhaust piping. I just vacuumed everything
out, I changed thermostates to the old one, same thing happens. I suspect
either the motherboard which has no lights to blink to show alarms, or the
gas valve which I had to replace couple years ago, But back then at least
the igniters would light up and shut off immediately, told me it was a gas
valve issue so replaced that and worked. All else looks clean and I smacked
as many relays as I could see, checked all the tubes to see if connections
are ok and seems ok. Even when thermostat is turned off, disconnected, when
I turn the furnace on it only immediately starts up the both blowers and
nothing else, no clicking, no safeties going on and off, no nothing. Anyone
here have a suggestion other than hiring an HVAC contracting firm to come in
and give me estimates? I know a board is about 50 bucks, easy to replace,
gas valve is about 150 easy to replace, what ever sensor should be cheap and
easy to replace. Any suggestions as to what to try next?

Thanks Hams, I know this is off topic, but I have gotten good advice from
this group before and there are no furnace newsgroups of any kind on my
server.
Thanks for any advice or tips or links
73

John Ferrell W8CCW

On Sat, 17 Dec 2011 10:00:22 -0500, Kickin' Ass and Takin' Names wrote:

On Fri, 16 Dec 2011 18:20:26 -0500, " Tuuk"
wrote:



Also -- how does your system dispose of condensate? Is there a
condensate pump? If it's not working, the system will start up then
shut down when it sense the condensate pump is not working.

This has been the prob with my Mom's gas furnace... the condensate
reservoir fills up and trips the float switch because the condensate pump
isn't working (or the drain line is frozen in my case). the fans run but
no gas, etc

On Fri, 16 Dec 2011 18:20:26 -0500, Tuuk wrote:

Hi

I have the Keeprite 075 condensing gas furnace. Only about 10 years old.
Honeywell pro 8000 thermostat. NUGM100EHB1 is the furnace.

My question is what happened all of a sudden yesterday when I think I
had a bit too much humidity in the air, why did the furnace fail?

Now when there is a call for heat on the thermostat, what happens is
both blowers run only. The exhaust blower venting out runs immediately
on start up, the main house blower starts immediately on start up. But
no clicking from the honeywell smart valve, no sparking or ignighting
beginning or trying. Nothing else is happenening. No gas is going
through the valve, no obstructions in either intake or exhaust piping. I
just vacuumed everything out, I changed thermostates to the old one,
same thing happens. I suspect either the motherboard which has no lights
to blink to show alarms, or the gas valve which I had to replace couple
years ago, But back then at least the igniters would light up and shut
off immediately, told me it was a gas valve issue so replaced that and
worked. All else looks clean and I smacked as many relays as I could
see, checked all the tubes to see if connections are ok and seems ok.
Even when thermostat is turned off, disconnected, when I turn the
furnace on it only immediately starts up the both blowers and nothing
else, no clicking, no safeties going on and off, no nothing. Anyone here
have a suggestion other than hiring an HVAC contracting firm to come in
and give me estimates? I know a board is about 50 bucks, easy to
replace, gas valve is about 150 easy to replace, what ever sensor should
be cheap and easy to replace. Any suggestions as to what to try next?

Thanks Hams, I know this is off topic, but I have gotten good advice
from this group before and there are no furnace newsgroups of any kind
on my server.
Thanks for any advice or tips or links 73

Is there a thermostatic switch on the hot air manifold?

On 12/17/2011 10:38 PM, jerry4 wrote:
On Sat, 17 Dec 2011 10:00:22 -0500, Kickin' Ass and Takin' Names wrote:

On Fri, 16 Dec 2011 18:20:26 -0500, "
wrote:



Also -- how does your system dispose of condensate? Is there a
condensate pump? If it's not working, the system will start up then
shut down when it sense the condensate pump is not working.

This has been the prob with my Mom's gas furnace... the condensate
reservoir fills up and trips the float switch because the condensate pump
isn't working (or the drain line is frozen in my case). the fans run but
no gas, etc

That would be the first thing to check. If not that, then I
would check the induced fan blower system that exhausts the
hot gasses.
You would want to make sure the flue pipe is clear, and
also the little tiny hole that is in the blower housing,
which is inside the nipple where the little usually rubber
hose connects. Many times that little hole will become
plugged and the pressure switch will fail to operate.
You can jump the float switch for a quick test.
You can also jump the pressure switch for a quick test,
but you have to start the furnace cycle first, let the exhaust
fan start running, and then jump the switch.
If you jump the pressure switch first, and then try to cycle the
furnace, it will see it as a bad pressure switch, and it will not
operate.
But in this case, the condensate reservoir is the more likely
culprit. That's a fairly common problem with those.