# TRANE XE90 getting no power, no red light



## reap70

I would like to start off by saying I'm not a complete dumbass, but I might have done a dumbass thing to my furnace.

Well, we just kicked on the heat for the first time this year and the furnace was blowing out cool air, probably more like room temperature air.  I went down and looked at it this morning half asleep and cold without my contact lenses in yet and moved my high limit switch to where it threw a spark then my furnace quit blowing air.  I went back to look at it a couple hours later, this time with my brain functioning.  I checked the "blinking red light" so I could look up the code and the blinking red light is not blinking or coming on at all.  I looked it up and the code is CHECK POWER.  I flipped the circuit breaker off/on, it was fine, and went back to the furnace where I flipped the power switch off/on a few times.  I noticed a very low humming noise like something is getting power.  Just to be thorough, I turned off the thermostat and checked again.  This time, as expected, there was no humming noise and still no blinking red light.

Right now, I have the thermostat off and will leave off for a few hours before checking again (is there a certain amount of time I should wait?  I read to leave off a few hours so I'm trying it).  If this doesn't do anything, any ideas?  Thanks in advance!  I will do some more searching in the meantime to see if I can find any ideas myself.


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## reap70

Update : Getting slow blinking red light!  Going to check with thermostat.  Will update in a few.


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## reap70

UPDATE #2 : OK, back to where I was in the first place.  Finally get to see the code I am getting and I am getting 4 flashes, which means OPEN HIGH LIMIT DEVICE.  I'll look around for this, but if anyone wants to chime in, you are welcome to!  Thanks again for the great help!  LOL


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## nealtw

Welcome to the site.
I found this video. The hum might br the fan motor, but I am no expert on this stuff.
[ame]https://www.youtube.com/watch?v=VJgMaoa9Cyw[/ame]


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## reap70

FINAL UPDATE : It was limit switch.  Just needed to bang it on the concrete floor a few times to get it to work.  It's an annual thing, so once I got power back, I figured I could figure it out.  

THANKS FOR ALL OF THE GREAT HELP EVERYONE!!!  HAHA!!!


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## reap70

Sorry Nealtw, didn't see your post.  I thought I was the only one who replied.  Thank you for your reply!


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## reap70

FINAL FINAL UPDATE (I HOPE :rofl : OK, it's NOW officially blowing out HOT AIR!!!  For some reason, the gas valve switch was in the OFF position!  :rofl:  I guess I should have checked the obvious possible solution instead of "Pavlov doggin'" it!  :agree:

NOW I DO BELIEVE IT'S TIME FOR :beer:!


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## slownsteady

Welcome Reap70. Sorry we couldn't help you more on your first thread. Glad you worked it out.


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## reap70

Well, I'm back to getting no power to the furnace.  Since the last time I chimed in, here is what has been going on.

1.  About 2 months ago, I was getting 3 blinking lights, which is a pressure switch error.  The furnace would try to start and quit.  It would repeat this like 5 times before giving up for a while, then after a few minutes, it would go through this cycle again.  I noticed the (intake fan?) was rattling and getting worse.  If I would bang on it a few times, it would eventually quiet and the furnace would run.  I did this until I replaced it.

2.  Things were working fine until about 10 days ago when it would give me the 3 blinking light code again, but I could get it going again.  It did this a few times until 5 days ago, the furnace died.  It's getting NO POWER AT ALL!  No blinking codes, no trying to start, nothing!  Since then, I replaced the circuit board (no improvement), bypassed the door switch (took the wires off the door switch and connected them together with a piece of metal), checked the filters (they were cleaned a couple months back), checked circuit breakers which are fine, checked the power at the on/off switch on the side of the furnace and it IS GETTING POWER (it runs to a power outlet and I plugged in a lamp. flipping the switch turns the lamp on/off).

So it looks like the power problem is between the power outlet where the lamp is plugged in (last place I can verify power) and the door switch? (I'm guessing that would be the place power would run before the circuit board?)  Like I said, I'm not an expert, but I am mechanically inclined and I don't want to go messing with stuff I don't know about without advice.  So my question is, where can it be between the power outlet and the door switch, if that is correct?  Also, would your solution target the pressure switch error?

THANKS IN ADVANCE!!!


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## nealtw

Your outlet goes out when you turn the furnace off, Does the furnace plug in there too, If yes, move the lamp plug to the other side of the outlet, if it is wired in to that box, open it up and check the connections????
I would think the power would stay on the outlet, so you could have a split outlet with a problem.


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## buffalo

First you say you have no power. Did you check with a volt meter or glow light ? When You open the bottom door there is a junction box , check there. Are wire nuts or connections tight?

Next , your trouble code . You have a high effiency furnace  , it has a draft inducer motor. That could be bad , the pressure switch could be bad , the intake or exhaust vents could be obstructed.  
http://homerepair.about.com/od/heatingcoolingrepair/ss/Furnace-Pressure-Switch.htm


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## reap70

@Neal, No the furnace doesn't plug into this outlet.  The on/off switch runs to the outlet and nothing is normally plugged into it, but the top plug in works, but the bottom one doesn't.  Hasn't since I can remember.  There is also some kind of attachment on the bottom of the outlet that runs to the humidifier too.


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## reap70

@buffalo, can you post a picture of the junction box?  Not sure what it is.  And I bet the pressure switch is bad.  I had some kind of problem with it in the past and hitting the switch is what got my furnace to kick on recently.


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## buffalo

It's just an electrical box. Power from your electric panel goes into the furnace . Inside there is a box that ties your Rome wire in with your furnace wires.


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## reap70

I took some pics if this helps.  Can you tell me what I need to look into?

#1  This is the outlet on the side of the furnace.  The part attached to the bottom has wires leading to a condensation control.






#2  Is this the junction box on the inside where the outlet is?





#3  The pressure switch which I took down when I put the fan in.





#4  I got a new fan about a month ago.  The old one was very noisy so I thought it was the problem.


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## reap70

Here are some more.

#5  Upper area.





#6  Center area.





#7  Bottom area.  I just replaced the control box.





#8  What is this small box?  It's in the bottom area.


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## nealtw

So when you turn the breaker off for the furnace you lose power to that outlet too?
So turn off the furnace breaker and remove the cover pull the screws on the outlet and just pull it out so you can see how it is wired and wire colors, then open the box on the inside and see how those wire are attached in there.
The second set of pictures are not showing up??


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## reap70

I have an on/off switch that goes to the outlet.






I will try what you said and try to take good pictures or else let you know in writing.  What do I need to do with this information?  Or are you walking me through some steps to diagnose?  The furnace has been running for years without any major problems and I didn't do anything other than change the intake fan and control box (3 times in the past 10 years, but this time, it probably didn't need changed).

Also, are the second set of pics showing up yet?  In #8, is that the junction box?  Well off to do what you suggested.  I'll let you know the results soon!  Thanks a million for the help!


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## nealtw

You getting power to the switch and the outlet, and don't appear to have power at the furnace, so the simple would be to think with vibration some wire may have come loose.
Buffalo was thinking I think that you were not getting power in there and if the power goes thru the outlet box then you check both???


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## reap70

@Neal, I checked the ones I could get to and tightened everything up, but nothing was really loose.  Below is what I did with pictures.



> So turn off the furnace breaker and remove the cover pull the screws on the outlet and just pull it out so you can see how it is wired and wire colors



















Here is what I have.  

1.  Coming into the outlet from the on/off switch are 3 wires, white, black, and green.  
     a. The white wire runs to the upper left side screw, 
     b. The black wire runs to the upper right screw, 
     c. The green wire runs into a screw cap, which runs into the hole in the back of the outlet into the furnace (junction box?).  Inside the box, it is grounded with a small screw.
2.  There are 2 wires, a white one running from the lower left side screw to the box at the bottom of the outlet, and a black one which runs from the hole in the back of the outlet from the junction box into box at the bottom of the outlet.
3.  Finally, there are 5 wires running into the hole in the back of the outlet (that runs into the box inside the furnace).  They are...
     a. the green wire explained above in 1c.
     b. a white wire which runs from the lower left side screw to the control box plug in "LINE-N" aka "E7"
     c. black #1 runs from the upper right side screw to the door switch
     d. black #2 runs from the lower right side screw to the control box plug in "EAC-H" aka "E18"
     e. black #3 runs from box under the outlet to the control box plug in "HUM-H" aka "E28"


So now what?  LOL


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## nealtw

Between the 2 screws with white wires, there is a little tab that connects the 2 screws.
Between the 2 screws with the black wires, that tab is missing, That would explain why you have no power to one side of the outlet.
So now the question is was that cut out for a reason or was that something that just happened.
Can you tell if it has been cut or melted or?
I would not fix it until you have more info!


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## nealtw

Yes I get the photos now figuring out the wiring is above my pay grade.


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## nealtw

Do you have a label that shows wiring diagram, the manual say it should be on the unit.


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## kok328

I see line power coming in to power half an outlet (bridge on hot side is removed), a transformer on the bottom of the J-box to run a condensate pump or humidifier solenoid and finally an outlet for an EAC (electronic air cleaner).
So with all this plugged in and switch turned on, you say you are not getting power to the door panel safety switch?


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## nealtw

kok328 said:


> I see line power coming in to power half an outlet (bridge on hot side is removed), a transformer on the bottom of the J-box to run a condensate pump or humidifier solenoid and finally an outlet for an EAC (electronic air cleaner).
> So with all this plugged in and switch turned on, you say you are not getting power to the door panel safety switch?



Not sure he tested for power.


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## kok328

reap70 said:


> @Neal, I checked the ones I could get to and tightened everything up, but nothing was really loose.  Below is what I did with pictures.
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Here is what I have.
> 
> 1.  Coming into the outlet from the on/off switch are 3 wires, white, black, and green.
> a. The white wire runs to the upper left side screw,
> b. The black wire runs to the upper right screw,
> c. The green wire runs into a screw cap, which runs into the hole in the back of the outlet into the furnace (junction box?).  Inside the box, it is grounded with a small screw.
> 2.  There are 2 wires, a white one running from the lower left side screw to the box at the bottom of the outlet, and a black one which runs from the hole in the back of the outlet from the junction box into box at the bottom of the outlet.
> 3.  Finally, there are 5 wires running into the hole in the back of the outlet (that runs into the box inside the furnace).  They are...
> a. the green wire explained above in 1c.
> b. a white wire which runs from the lower left side screw to the control box plug in "LINE-N" aka "E7"
> c. black #1 runs from the upper right side screw to the door switch
> d. black #2 runs from the lower right side screw to the control box plug in "EAC-H" aka "E18"
> e. black #3 runs from box under the outlet to the control box plug in "HUM-H" aka "E28"
> 
> 
> So now what?  LOL



What they have done here is brought in LINE power to the top of the convenience outlet.
This power is shared and also feeds the furnace.  The other two black wires are "outputs" from the control board to control the humidifier "HUM-H"/"E28" and electronic air cleaner "EAC-H"/"E7".  The air cleaner plugs into the bottom of the outlet and the transformer under the J-box runs the water solenoid for the humidifier.  Pic #8 is yet another transformer for low voltage control power (i.e.- the thermostat, etc).
With the switch turned on, you should have power to the top of the outlet and the door switch and then onto the control board.
If no power, then back up and see if you have power coming to the switch.
Test these areas for power and lets see where it leads us next.


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## nealtw

kok328 said:


> What they have done here is brought in LINE power to the top of the convenience outlet.
> This power is shared and also feeds the furnace.  The other two black wires are "outputs" from the control board to control the humidifier "HUM-H"/"E28" and electronic air cleaner "EAC-H"/"E7".  The air cleaner plugs into the bottom of the outlet and the transformer under the J-box runs the water solenoid for the humidifier.  Pic #8 is yet another transformer for low voltage control power (i.e.- the thermostat, etc).
> With the switch turned on, you should have power to the top of the outlet and the door switch and then onto the control board.
> If no power, then back up and see if you have power coming to the switch.
> Test these areas for power and lets see where it leads us next.



When the switch is turned on he has power to the top of that outlet.


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## kok328

Ok, then he should have power into the door switch and out of the switch to the control board.
Trane has a yellow 5 amp blade style fuse on the control board.  If this is blown the entire unit will shut down.
check for power up to the control board and also see if the fuse is good.


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## reap70

I went to test for power and the tester slipped out of my hands and the black tester wire broke (yes I bought a cheap one, it was the only one our local hardware store had).  I have to get a new tester and will let you all know.  The hardware store has a tester with a light on it, so I will at least know if power is going there.  I can't drive, so it's a pain in the *** getting to the next town over with better hardware stores.  Thanks for all of the great help!


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## slownsteady

A couple of thoughts: the hot side of the outlet isn't bridged (small metal tab) because the lower outlet should only be hot when the furnace is running; (probably a plug-in EAC? or extra humidifier or something) The black wire on the top outlet brings power to the furnace and the furnace sends power back to the lower outlet when appropriate.
@reap70; while you have the box open, ground your outlet.


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## nealtw

did you find the fuse.
[ame]https://www.youtube.com/watch?v=UnsaZa-5Duc[/ame]


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## reap70

Sorry for the delay in responding.  We got space heaters and I needed a break from this.  So I got a tester and also drew out an awesome diagram!  
	

	
	
		
		

		
		
	


	




At the top, it shows 3 wires coming into the outlet that come from the on/off switch.  The black one goes to the top screw on the right.  The white one goes into the top screw on the left.  The Dark Green one goes into a screw cap, then through the hole in the middle of the plug and into a ground screw.

I tested all 4 screws for power with the tester and the tester lights up for all screws except the bottom right one, as you all pointed out earlier doesn't have the small clip connecting it to the one above it.

As far as the 4 screws, the top left one has the white wire from the top going into it.  The bottom left one has 2 wires, one leads to the box under the plug, the other leads to the control box Line-N, E7.  The top right one has 2 wires (blk & blk1), the one going out the top and the other goes to the door switch. (I also tested the door switch wires and it is showing no power.  The other door switch wire goes to the control box LINE-H, E15?)  The lower right one, with no power going to it, has 1 wire (blk2) which leads to the control box EAC-H, E18.  There is also a wire coming from the bottom box (blk3) which leads to the control box HUM-H, E28.  

After I typed this, I see I already explained it.  LOL.

Should I just go ahead and put a new outlet in?


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## reap70

nealtw said:


> did you find the fuse.
> https://www.youtube.com/watch?v=UnsaZa-5Duc



Yes the fuse is good.  I put a larger amp fuse in, 30 I think, because the 5A blew.


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## reap70

kok328 said:


> I see line power coming in to power half an outlet (bridge on hot side is removed), a transformer on the bottom of the J-box to run a condensate pump or humidifier solenoid and finally an outlet for an EAC (electronic air cleaner).
> So with all this plugged in and switch turned on, you say you are not getting power to the door panel safety switch?




That is correct.  I got a line tester and it is not lighting up when I connect the two wires to the switch.


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## reap70

kok328 said:


> What they have done here is brought in LINE power to the top of the convenience outlet.
> This power is shared and also feeds the furnace.  The other two black wires are "outputs" from the control board to control the humidifier "HUM-H"/"E28" and electronic air cleaner "EAC-H"/"E7".  The air cleaner plugs into the bottom of the outlet and the transformer under the J-box runs the water solenoid for the humidifier.  Pic #8 is yet another transformer for low voltage control power (i.e.- the thermostat, etc).
> With the switch turned on, you should have power to the top of the outlet and the door switch and then onto the control board.
> If no power, then back up and see if you have power coming to the switch.
> Test these areas for power and lets see where it leads us next.



No power to the switch.  What should I try next?


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## reap70

slownsteady said:


> A couple of thoughts: the hot side of the outlet isn't bridged (small metal tab) because the lower outlet should only be hot when the furnace is running; (probably a plug-in EAC? or extra humidifier or something) The black wire on the top outlet brings power to the furnace and the furnace sends power back to the lower outlet when appropriate.
> @reap70; while you have the box open, ground your outlet.



YES!  Now that you mention this, I do believe that when I had something plugged into the bottom outlet, it only worked when the furnace was running.  That is why the tab it removed!  (Like you said, you learn something every day!  LOL)


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## reap70

Just a thought.  I'm starting to understand this more.  Should I run a new wire from the door safety switch to the top screw on the outlet?  It's starting to look like maybe that wire is bad since it runs directly from point A to point B.


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## kok328

If you have power to blk1 and blk2 but not at the door switch then yes it would seem that you have a bad connection/wire.


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## kok328

> I tested all 4 screws for power with the tester and the tester lights up for all screws except the bottom right one, as you all pointed out earlier doesn't have the small clip connecting it to the one above it.


This isn't good.  You should only be seeing power at the top right (blk1 & blk2).
Also, remove the 30 amp fuse ASAP !!!!!
If the 5 amp blew then you have a short somewhere in the control circuits 24VAC as explained earlier.


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## reap70

kok328 said:


> If you have power to blk1 and blk2 but not at the door switch then yes it would seem that you have a bad connection/wire.



I have power to blk1 (top right), but not blk2 (bottom right).  I have no power at the door safety switch either, which is where blk1 runs directly to.


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## reap70

kok328 said:


> This isn't good.  You should only be seeing power at the top right (blk1 & blk2).
> Also, remove the 30 amp fuse ASAP !!!!!
> If the 5 amp blew then you have a short somewhere in the control circuits 24VAC as explained earlier.



The fuse blew a couple years ago, but I'll change it back.  When I tested, I put one end of the tester on the left side and the other on the right side.  I guess I should touch one end of the tester to a screw and the other to a ground, eh?  My bad.  I'll try that tomorrow.  

I'll also try to find a new wire to run from the top right screw to the door switch.


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## slownsteady

The 30 amp fuse may have brought on these additional problems. It is providing no protection for the circuits on your unit.


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## buffalo

Do you understand how to use a volt meter? If you touch both leads to a hot connection you will read 0 . The meter measures differantial . One lead to hot , one lead to common . There is a junction box in that furnace where primary voltage enters. You need to put the meter to that black wire in that box , and a white or ground wire with the other lead. 

The very first step here is knowing if the furnace itself is getting power.


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## reap70

I'm bringing this post back to life because I never did get it working.  I got a very nice volt meter tester and I am getting 122 V to the door switch, which I bypassed and goes directly into the control board.  So yes, the control board is getting power and also the 5A fuse is good.


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## kok328

What's your voltage off the secondary of the transformer?


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## frodo

if you have an owners manual,  it should tell you what the slow blink red light means



[ame="https://www.youtube.com/watch?v=iab6PL_B9fY"]https://www.youtube.com/watch?v=iab6PL_B9fY[/ame]


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## reap70

Slow blinking light is "no call for heat" I think.  I wish I had any blinking light.  LOL

"What's your voltage off the secondary of the transformer?"

Not sure which one I was supposed to read, but

TOP LEFT = .000
BOTTOM LEFT = 122.4
TOP RIGHT = 0.1XX
BOTTOM RIGHT = 0.480

From what I have read, the one on the left is correct at 120V, but should the right side read 24V?  OMG, I hope this is it!


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## kok328

Your transformer converts from 120v to 24v. 
120v is primary
24v is secondary
Don't know exactly what you checked but this could be a problem.


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## reap70

Mine looks like the one in the picture.  I'm guessing one side is the 115 V input and the other is the 24 V output.  When I touched each post with one end and grounded the other end, I got the results above.  So it looks like there is 115 (122 V in my case) going in, but nothing coming out.  Is this right?  I'm going to buy the part and switch it out anyway.  I'll post back with my results.  In the meantime, if anyone wants to confirm my diagnosis, feel free to!  Thanks!


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## nealtw

sounds right.
[ame]https://www.youtube.com/watch?v=IIGhKLdCk7U[/ame]


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## reap70

Yeah, it's me again.  Seems like forever that I have been at this.  I just end up finding a work around, like window AC units, portable heaters, etc.

Anyway, right now, I'm getting the "no call for heat" code, slow blinking red light.  The problem is, the W connection on the circuit board is throwing sparks and blows the fuse whenever a "call for heat" is initiated.  I read elsewhere to try a jumper wire on the control board from the "R" to the "W" and it's throwing sparks until the fuse blows still when I do that.  Then, I hooked up another control board that I have (not sure if it works or not), but it does the same thing.  

Another test I did (on accident) was touch the "W" (call for heat) wire to the "Y" spot on the control board (this spot calls for the AC to run) and the furnace runs like when you turn the thermostat to the "ON" position (from AUTO).  It just blows air out, neither hot nor cold.  Neither the AC not the flame kick on.

So something is causing the "W" to spark.  Wondering if a wire was plugged into the wrong spot on the control board?  One of the last things I did was change the transformer.  Could plugging wires to it wrong cause this?  Thanks to all who have helped me out up to here and in the future.  Kind of fun trying to figure this out anyway, eh?  LOL


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## nealtw

Sparks are never good, did you measure the voltage you are getting.


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## nealtw

http://www.justanswer.com/hvac/7roty-taking-off-thermostat-noticed-spark.html

This is an interesting read, sounds like you may have short like the thermostat is wired wrong.


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## reap70

I read that to test to see if it's the thermostat causing the problem, remove the "R" & "W" wires on the control board and run a jumper from the "R" to the "W" on the control board.  This is supposed to make the furnace run, or have a constant "call for heat".  I tried this and I got sparks again.  When I ran the jumper from the "R" to the "Y", the furnace ran.  So the same thing happens when it runs through the thermostat as it does when it does not run through the thermostat.  And the wire that was running from the thermostat to "W" was indeed the correct "call for heat" wire because it only became active when I turned on the heat and turned the desired temp up higher than the actual temp.  When I did that, that is when the sparks happened.  AND I did this with 2 different control boards.  They both may be bad, but before I buy yet another control board, I want to make sure I need another.

Next time I work on it, I will check the voltage.  What are you wanting me to check the voltage on?  In other words, where do I put the red and black wire from the volt meter?  LOL


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## nealtw

I am just wondering if you are getting more than 24 volts. after that it is above my pay grade? We need someone with more knowledge than me.


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## nealtw

[ame]https://www.youtube.com/watch?v=eBYunyrImf0[/ame]
[ame]https://www.youtube.com/watch?v=0HiMJznAKKY[/ame]


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## buffalo

The tstat is just a switch , no different than a light switch. When you jump out the red and white terminails your just bypassing the switch and turning the heat mode on . I know that dosn't help you , but just so you understand what your doing .


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## nealtw

I take it with out that gauge you can run these tests with a hand full of fuses.


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## reap70

Sorry for the delay.  I measured the V on the control board, and when I touch the "R" to the "W" or "Y", the meter read 28.74 on both.  Is that what you are wanting?  

Now remember what I said earlier.  When I jump the "R" to the "W"(heat), it throws sparks.  When I jump the "R" to the "Y" (cool), the blower kicks on.

I'm wondering if I connected a wire to the board in the wrong spot elsewhere?  Maybe there is a diagram or post showing the correct wiring setup with the other wires on the control board?  Or are both of these boards just shot?

I hope this helps.  If you need any more info, let me know.


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## nealtw

If you are blowing fuses you have a short somewhere, either wiring wrong or  wire touching ground somewhere.
I don't know enough to say anything about the board. but if the short is on the board I guess that would be the problem.


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## nealtw

The test in post 56 can be done with a hand full of fuses and then you would now witch wire or circuit that  is the problem.


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## kok328

Something is wired wrong.  Jumerping W & Y should not do anything, especially not turn on the blower fan.
Also, you should not be getting voltage when checking R to W & Y.
There should be a wiring diagram on the back of the removable door panels.


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## nealtw

kok328 said:


> Something is wired wrong.  Jumerping W & Y should not do anything, especially not turn on the blower fan.
> Also, you should not be getting voltage when checking R to W & Y.
> There should be a wiring diagram on the back of the removable door panels.



Thanks for dropping by again , we need all the help we can find.


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## nealtw

So to recap
furnace blowing cold air, no blinking light, 
adjust high limit switch, stopped the fan
Humming noise detected
Later got a slow blinking light

Later, same day, 4 flashes, which means OPEN HIGH LIMIT DEVICE

later same day, banged limit switch on floor and got it to work

And found gas was turned off, all was well.

Why was the fan running in the first place, limit switch out of adjustment, you have played with this before?


2 month later. blinking three lights  pressure switch error , replaced intake fan.

1 1/2 month later no power, no lights , no run replaced board no run.

Now we have found power at the unit.

But now we know that the fuse had been replaced with over sized when a short was detected years earlier.

So for years it drew to many amps thru any number of component. Any wires to the thermostat could be damaged anywhere between the furnace and the thermostat. Any component or controller that uses low voltage could be damaged.

I would inspect the boards old and new for burn marks and or melted solder.

I would also bring the thermostat to the furnace and hook it up with a short cable, that will prove the thermostat wires are not the problem.

Near as I can figure that fuse is all about the thermostat and the wire going to an outside unit, there must be a short in one of them.


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## kok328

If the thermostat wires were disconnected from the control board when he jumered it out for heat, then we have eliminated (for now) the thermostat and thermostat wires.
Was this the case when R to W was sparking?
Although I'm thinking more along the lines that the control board is wired in wrong.
Can we see pics of the back side of the cover panels and wires to control board?


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## nealtw

kok328 said:


> If the thermostat wires were disconnected from the control board when he jumered it out for heat, then we have eliminated (for now) the thermostat and thermostat wires.
> Was this the case when R to W was sparking?
> Although I'm thinking more along the lines that the control board is wired in wrong.
> Can we see pics of the back side of the cover panels and wires to control board?



I am way over my head here but there must be short that caused the fuse to go years ago. so what gets damaged when forced to work with a bigger fuse.
If the new board was put in without solving the short, the new board could be damaged too..

I would think checking anything low voltage for shorts would be where to start.
Now for some reason most of his photos are not coming up for me.


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## nealtw

This lil popper would be handy.
https://arnoldservice.com/product/lil-popper-control-circuit-breaker-tool-5-amp/
[ame]https://www.youtube.com/watch?v=0A1nV3-Dt0M[/ame]


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## reap70

kok328 said:


> Something is wired wrong.  Jumerping W & Y should not do anything, especially not turn on the blower fan.
> Also, you should not be getting voltage when checking R to W & Y.
> There should be a wiring diagram on the back of the removable door panels.



Here is what I am dealing with.  Maybe you can figure it out a little better than I?


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## reap70

MORE PICS!!!

Here are some real time images.

Thermostat.  
	

	
	
		
		

		
		
	


	




Connections to thermostat.  
	

	
	
		
		

		
		
	


	




2 of these go to the 24V converter.  Other goes to Fan Motor.  
	

	
	
		
		

		
		
	


	




Not sure what these are for except the door switch.


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## reap70

A COUPLE MORE.  CAN ONLY POST 4 PER.


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## reap70

Trying to get the video I took on here.  LOL.  Hope this is it.  Let me know if you can see it or not.  And also, thanks again to you guys for the help, especially you neal!

https://www.facebook.com/reap70/videos/vb.100000492048868/1625058497520536/?type=2&theater&notif_t=video_processed&notif_id=1483909447249952






https://www.facebook.com/reap70/vid...f_t=video_processed&notif_id=1483909447249952


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## nealtw

I am not getting a video, and I will let someone that knows help with the wiring.


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## reap70

yeah, i set the video to where only i can see it.  i'll change my settings to public so you can click on the link and it should show up.  let me know if you can see it or not.  and neal, you have been great through all of this!


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## nealtw

reap70 said:


> yeah, i set the video to where only i can see it.  i'll change my settings to public so you can click on the link and it should show up.  let me know if you can see it or not.  and neal, you have been great through all of this!



Did you say you had changed the control board and which two wires are giving you that spark, and that spark does not blow the 3 amp fuse?


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## nealtw

I found this at 
https://quizlet.com/77564403/unit-61-troubleshooting-electric-heat-flash-cards/
An electric furnace that runs continuously, regardless of the thermostat setting probably has?	
A stuck sequencer.
&#57410;&#57494;
An electric furnace that does not operate, regardless of the thermostat may have?	
A bad sequencer coil.
&#57410;&#57494;


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## nealtw

[ame]https://www.youtube.com/watch?v=lliFA8TwCgM[/ame]


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## reap70

I finally got around to getting a brand new control board and hooked it up and still getting a spark when jumping the R (hot wire) & W (call for heat) spots on the thermostat connections on the control board.  And the R & Y (Call for cold) still works ok; ie, blower motor starts.

And to answer an above question, yes it does blow the fuse.

I'm ready to throw in the white towel on this and call an expert.  Better start saving some money before summer hits!  LOL


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## slownsteady

Just a random thought, but are the other ends of those wires hooked up to the right terminals? If the other end is cross wired, you would see sparks when you make contact at this end.


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## reap70

I have pondered the same thing.  But I have horrible news.  Last week, we lost our house to a fire.  We were not home, but our dog Hogan passed away.  We may never figure out the solution.  I want to thank you all again for your patience and time you took to help me.


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## nealtw

Sorry for the loss of the home and especially the dog we know they are family members.

Will you covered by insurance?


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## reap70

Yes, we have insurance thank goodness.  I have considered tearing down the house and trying to get a cheaper better for closure or auction sale house.  We still have time to decide.


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## nealtw

It's great to make lemonade out of lemons but it's an emotional time to make decisions, good luck which ever way you go.


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