He definitely needs to slow down a bit and wait for a few more
TSR tips to show up.
Trouble shooting starts with the basics, not what one suspects
unless the symptoms are a known, recurring event. By setting
up the system for a normal start sequence, and waiting the
appropriate amount of time, all of the issues with the T-stat
would not have been.
If the system was reset and things were started over again I
would wager that the unit would work again. This time, do
the test with the cover in place. Check for normal operation,
first, then find out why things are not working. Find the path
of electricity (hence, the logic of the circuit), and follow
it until the path stops. Just bumping the interlock would not
cause any of the other safeties to engage, and would restart
the start up sequence.
Just as with physics, observation with repeatable results is
necessary to figure out what is going wrong. As for his AC, I
wonder if there is a blown fuse out in the fusible disconnect
On Wed, 11 Dec 2013 11:49:18 -0600, Irreverent Maximus wrote:
This morning, I pulled the plug, and then, one by one,
disconnected *every* wire I could, and cleaned the contact
surfaces, and reconnected them.
I also blew compressed air over the boards, and tapped on
each solenoid of the gas valve and relays in the fan-control
This took about an hour. When I powered it back up, I heard
a click click click, and then a small whoosh, and then after
a while, a bigger whoosh, and finally the blower.
The house is toasty right now - but it has only been working
for a couple of hours. Thanks for all the help & advice!
I'll report back, to let you know how it progresses along
over the next day or three ...
On 12/11/2013 12:33 PM, email@example.com wrote:
In one of the Scott Adams "Dilbert" books, he tells
of a company that called a copier repairman. The
engineers had dissembled (dismembered) the machine,
and written notebooks of theories on why it wasn't
working. The problem was someone put toner in the
imager container. Normally a half hour diagnosis and
fix. To reassemble the copier and reset all the timing
gears took several days.
On Wed, 11 Dec 2013 13:12:37 -0500, Stormin Mormon wrote:
A *lot* of things get fixed, simply by throwing parts at
the problem. Nothing wrong with that. Sometimes the person
throwing the parts actually knows what they're doing; sometimes
Take the oft-cited case of vibration when braking? Must be "warp",
right? The rotors must be warped like a potato chip. Solution?
Replace (or turn) the rotors. Right? Everyone knows this, right?
When *I* had vibration while braking, I tried to measure this
so-called "warp". You can't measure it on the car (that would
be runout), so, I measured it off the car. Hmmmm.... there was
no warp. Huh?
Turns out, for normal people (not racing braking systems), warp
just doesn't really happen. While a ton of suspension components
can cause vibration at various speeds, the classic brake-related
vibration at speed is caused, usually, by disk thickness variation
caused, most often, by braking deposits, building up over time.
The solution, once you *understand* that, is to change your
braking habits (so as not to build up those deposits).
Yet, if you don't bother to understand what causes the vibration,
and you simply replace the rotors, you'll solve the problem
quickly, but it will eventually return. And, most importantly,
you'll be solving the problem without understanding the cause,
which means you'll think your entire life that your rotors
are warping. You might even vainly try to buy beefier rotors
in the hope that they won't "warp" as much. Which means you'll
be solving the problem with the right solution but for the wrong
Anyway, same thing with just jumping the red wire to the white
wire. If I didn't understand first what the red wire was supposed
to do, and what voltage it was supposed to have, and what effect
it was supposed to have on the furnace, etc., then I would be
Of course, had I just disassembled everything and reassembled
it, in this case, I would have solved the problem sooner, as
now it's all working after I disconnected *every* wire, and
reconnected them after cleaning them. I also tapped ever solenoid
and relay I could find and blew the whole thing out with
At the moment, it's working! Thanks to everyone! I very
much appreciate the help.
On Tuesday, December 10, 2013 5:36:20 PM UTC-5, Danny D'Amico wrote:
Turn furnace switch off. Connect the red wire to the white wire.
Turn the furnace switch back on. If the furnace doesn't fire
up, it's not the thermostat. It's unlikely it's the thermostat
to begin with, so why waste time on all kinds of tests when there
is a simple and very direct method?
On Tue, 10 Dec 2013 15:08:26 -0800, firstname.lastname@example.org wrote:
There is no furnace switch, that I know of.
The wires come directly into the furnace from the outside.
Of course, I can shut off a breaker ...
OK. I have the breakers off. I'll wait a few minutes now.
From another post, before I ruin something, is this correct?
a. Connecting red to white should fire the furnace
b. Connecting red to green should turn the blower on
Is this where I should make those jumper connections?
BTW, normally I *measure* stuff (voltages usually) before jumping
from one point to another; but I would need to know what *two*
points to measure. Based on Stormin' Mormon's prior post, I'll read:
A. Red to White (AC voltage) ... is this what I should read?
B. Red to Green (AC voltage) ... is this what I should read?
NOTE: I haven't finished reading everything, so, if I'm repeating,
I've buttoned up the thermostat. It just took me a while to report
back because I was trying to figure out how the darn furnace works
and what the parts were...
On Tuesday, December 10, 2013 7:26:39 PM UTC-5, Danny D'Amico wrote:
May be different in your part of the world and I'm not
sure what that code actually says. But every furnace I've
ever seen there has been at least one emergency switch with
a red plate. Sometimes it's in the basement stairwell,
with the furnace in the basement.
Yes, you can jumper from the red to the white on the
right side, the R and WH terminals.
If you hadn't put it back together, you could have just connected
the red and white together there.
Some units will use a cord plugged into a receptacle. Usually
this is only for control voltage, but in his case the control
power supply also powers the blower. He might have a disconnect
that he has not noticed. Usually this is required, but if in
eyesight of the panel I don't think it is in this case.
On Tue, 10 Dec 2013 18:00:40 -0800, email@example.com wrote:
The California-specific PDF that I was sent says what you say,
in that a switch must be within sight of the furnace; but it
also allows for the door switch serving double duty as that shutoff.
Literally, that PDF says: "a disconnecting means must be located
within sight of, and readily accessible to, the furnace. The blower
door switch may be acceptable in some areas as a disconnecting means".
So, from that, I must assume the blower door switch is *my*
disconnecting means. I'll snap a photo of the electrical wires
tomorrow (in the daylight) to show you what mine looks like.
On Tue, 10 Dec 2013 18:00:40 -0800, firstname.lastname@example.org wrote:
I see now that the red (which is 24 volt power), is "connected" to
the white (which is the indication of the call for heat).
1. Red wire is 24VAC hot.
2. Thermostat "calls for heat" by connecting Red to White.
3. Thermostat "calls for fan" by connecting Red to Green.
So, if I manually made those connections, it would bypass the thermostat.
(I didn't know this at all, earlier today ... so I'm just repeating what
I learned today).
On Tue, 10 Dec 2013 20:54:12 -0600, Irreverent Maximus wrote:
I'll look again tomorrow, by following the power wires, to see
where they go - and if there is a shutoff switch that I didn't
It's dark and cold downstairs now, so I'll wait for daylight where
I can snap better pictures for you.
The electrical code in the US demands that the furnace have
a permanent connection to the power source...no plugs allowed.
But when I asked the electrical inspector if I could put a plug
on it so I could run it from a generator, he said, "no problem".
The electrical code is very strict...except when it isn't.
He might have a disconnect
On Tue, 10 Dec 2013 23:56:54 -0600, Irreverent Maximus wrote:
I must apologize for having never even looked before this
morning to see how to turn off the furnace (I just hit the
breakers up until now).
Following the power cord with a flashlight in the dark mouse-infested
recesses, I see it terminates on an inaccessible back wall, in a
normal 120V three-pronged power cord:
I pulled the plug this morning, and wished that I had not,
since it's a bear to get back on the wall, because of the
ductwork in the crawl space.
So, next time, unless it's an emergency, I'm gonna flip
If I ever get a round to it, I'll see if I can hook up
a switch on the outside of the furnace, where that wire
enters at the door switch.
On Wed, 11 Dec 2013 03:54:03 +0000, Danny D'Amico wrote:
No shutoff switch.
And the breaker is on another floor.
So, most of the time, I leave it powered up.
I made the mistake of unplugging, this morning, and wished that
I hadn't (since it's really not easy to put the plug back):
So, when I have the inclination, I'll see if I can put
a normal 120V switch mounted on the side of the furnace.
I hate it when installers save a buck ... (their buck) ... as
I agree; it should have a switch mounted on the side of the furnace.
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