Bad Thermostat?

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  #41  
Old 12-06-16, 09:21 AM
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Thanks!
Here's setup I went with...I placed the meter down inside the chassis on bottom, where it could lay flat. I put the black probe through a hole on bottom left of chassis, where I unscrewed the door. Pulled purple fuse partially out, just enough so that I can get my multi meter probe to make contact with the "blade" on the fuse.

READINGS:
Touched the red probe to one side of the fuse and got no reading 0.
Touched the red probe to the other side of the fuse and got no reading 0.

FWIW, I was also able to make contact with the blade without pulling the purple fuse at all but got the same readings.

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  #42  
Old 12-06-16, 09:34 AM
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Check the transformer for power.

Black and orange for 240vac.
Red and brown for 24vac.
 
  #43  
Old 12-06-16, 11:11 AM
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Originally Posted by PJmax

Check the transformer for power.

Black and orange for 240vac.
Red and brown for 24vac.
Originally Posted by Bob14525
You only need to check for 240VAC at the transformer if there is no 24VAC at the output (top terminals) of the transformer. If 24VAC is not present at the top terminals of the transformer, then check for 240VAC across the bottom terminals. Just be very careful that your probes don't touch anything but the terminals.
Please confirm: 24vac (Red and brown) should be checked 1st as per Bob "...If 24VAC is not present at the top terminals of the transformer, then check for 240VAC".

That said, and keeping the meter and black probe setup...How/where exactly do I touch the red probe to the Red and brown, to determine if 24vac is present?

Then, if there is no 24VAC at the output (top terminals) of the transformer, how/where exactly do I touch the red probe to the Black and orange, to determine if 240vac is present?

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Last edited by PJmax; 12-06-16 at 12:22 PM. Reason: labeled pic
  #44  
Old 12-06-16, 12:23 PM
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Both the 24V and 240V terminals are AC voltage, so there is no polarity. It doesn't matter which meter probe (red or black) you connect to each terminal. If there isn't enough of the terminal exposed to get the probes on it, turn the power off and pull the wire terminals up a little bit so that there is enough of the terminal exposed. Measure the voltage across the top terminals (24VAC) first. It likely will read 0 volts based on your previous measurement. Assuming it's 0 volts, then put your probes on the bottom two terminals and see if you measure 240VAC.
 
  #45  
Old 12-06-16, 12:24 PM
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The probes should be able to fit in the orange and black terminals.

You can slide the red and brown terminals up slightly to expose the metal blades of the transformer.

I also labeled your picture.
 
  #46  
Old 12-06-16, 02:20 PM
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A bit confused...
Do I still have to put the black probe on the metal chassis and use the red probe to test?
When I test for 240vac, do I still keep my multi meter set to AC 200 Volts or raise it to 750?
 
  #47  
Old 12-06-16, 03:21 PM
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For checking the 24vac.... you put one probe on red and one on brown terminal.
For checking 240vac.... you put the meter to 750vac .... one probe on orange and the other on black.
 
  #48  
Old 12-06-16, 03:22 PM
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Put the probes directly on the terminals (one probe on each terminal), not one on the chassis. When measuring the 240VAC, set the meter to the 750V scale.
 
  #49  
Old 12-14-16, 01:54 PM
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Originally Posted by PJmax

Good to see you back. You'll be needing A/C soon.
Sooner then I thought....DAMN La Nina! 85 with a heat index of 90 today...Merry Christmas!
 
  #50  
Old 12-14-16, 02:19 PM
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Checked for 24vac, as follows....
Power on...Meter to 200vac...
The probes fit in bottom of top terminals (red and brown), where arrows were added to pic...
No reading.

Checked for 240vac, as follows....
Power off...Slid the bottom terminals (orange and black) down slightly to expose the metal blades of the transformer. Power on...Meter to 750vac...Placed one probe on orange and the other on black...
Reading as high as 4 (four).

FWIW, I found this video but my connectors appear to be individual wires plugged into a non-removable panel on the motor, rather than a high voltage plug and low voltage plug, which he disconnects, beginning @4:54.
https://www.youtube.com/watch?v=kFyxOigkh9c My connectors on motor:
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Last edited by c1351996; 12-14-16 at 02:43 PM.
  #51  
Old 12-14-16, 02:53 PM
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From what you've written, it appears that you don't have 240VAC present at the air handler. Either you have a circuit breaker that has tripped, or there is a switch that is turned off (many furnaces/air handlers are wired with a switch located near the unit to shut off power to the unit). Perhaps you need to hire an electrician to determine why you don't have power at the unit.
 
  #52  
Old 12-15-16, 11:46 AM
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No circuit breaker has tripped, as we determined early on. FWIW, that's how I turned the power on & off, when I'm testing it.

A switch that is turned off? Such an important switch is not on the wiring diagram??
 
  #53  
Old 12-15-16, 01:35 PM
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The switch I'm referring to is usually added by the installer, so it won't show up on the wiring diagram. Since it appears that you don't have power going to the unit, someone will have to inspect possibly trace the wiring to determine why there is no power present.
 
  #54  
Old 12-19-16, 01:03 PM
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Are you referring to the safety switch, which turns off the unit, if flooded?
 
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  #55  
Old 12-19-16, 01:59 PM
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No, that safety switch shuts down the A/C system if the condensate tray overflows because of a plugged condensate drain line. You (or an electrician) need to inspect the AC wiring to see how the 240VAC gets to the air handler.
 
  #56  
Old 03-03-17, 01:37 AM
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Which coupon would you use?

Time to call a pro...
So, Since we know I need a repair but it's also time to have my yearly "tune up", during which the tech will obviously find the issue...Which coupon would you use?

1) FREE a/c service call *with repair* ($89 without repair)
Coupon must be presented at time of service. Cannot be combined with other offers or discounts. Some restrictions apply.

2) $89.00 Heating and Cooling Tune-up!
19-Point Heating or Cooling Tune-Up
Breakdown & Utility Bill Savings Guarantee!
(Reg. $136, Save $47)
Coupon must be presented at time of service. Cannot be combined with other offers or discounts. Some restrictions apply.
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  #57  
Old 03-03-17, 07:17 AM
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Normally when you use the same company they don't use a coupon.
If both those coupons are from the same company then it really doesn't make much of a difference which one you use.

At the current time.... repair is more of a pressing matter over routine service.
 
  #58  
Old 03-03-17, 10:08 AM
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Those special offers are just ways to get their foot in the door, they don't usually cover much.
I'd not bother with those, and just put a service call in to your preferred company.
 
  #59  
Old 03-03-17, 02:36 PM
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Thanks!
The offers are both from one company that is at the top of my short list, after doing a bit of research, to find my preferred company. Sounds, like the winner is coupon #1) FREE a/c service call *with repair* ($89 without repair).
 
  #60  
Old 03-07-17, 08:16 PM
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OK, I bit the bullet and called in a tech for a service call...
He came out and first checked the thermostat and then went right for the breaker inside the unit, at top...Power coming in...No power going out. Then he went outside to the condenser and found a wire burnt out, at the top. $89 for diagnostics OR $350 for repair (replace breaker & repair top of wire).
What would you do?

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  #61  
Old 03-08-17, 11:39 AM
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System broke 6 months ago. Pay the $350 and get on with your life.
 
  #62  
Old 03-08-17, 02:58 PM
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I replaced the breaker ($59 at local electric supply store) and repaired the wire, in the condenser, as recommended...I now have a/c! Total out of pocket $123 ($64 diagnostics + $59 breaker) vs. quote of $350 = SAVINGS of $227! Thanks to all, who helped along the way!
 
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