Question about Heating & Cooling

Open Question

How i get an electrical diagram of the main board of the Console and the external unit?

My air conditioner blow a fuse on the main board. I found on the external unit the the transformer that supply 24vac to the relay that operate the blower and the compressor was dead. The primary of the trx was open. I install a new trx and replace the fuse. After about 5 minutes the fuse burn again and the primary of the trx was burn. So i decided to change the relay that is activated by the trx that receivew the power from the main board and also change the capacitor at the exxternal unit. During the replacement of the relay one of the wires got loose on the old relay and when i connected everything to the new relay i didnt know were that white wire goes so i connected to one of the ac inputs to the relay. I install a new fuuse to the main board and tried to turn on the console with the remote but the console wont turn on. I check the fuse and the fuse is fine. I think that the white wire is wrong installed because is an ac input to the main board. So i ask for a diagram of the board. Also the model and seria of the outside unit is Model: SCU10A24A-4A sn:8498F21102 Help me, thanks

Posted by on


6 Suggested Answers

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

A 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
The service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
Good luck!

Posted on Jan 02, 2017

  • 75 Answers

SOURCE: Air Conditioner malfunction

Hi, Sounds like you have a short in the control circuit to me. Turn off all power going to the unit. Write down or otherwise mark the wires leaving the control board going to the thermostat. Remove them from the control board. Replace the fuse. Turn power back on and see if the fan still runs. If it does, check and or replace the heat limit switch that brings the fan on during the heat cycle. It may just need adjusted. If the fuse blows, I would think that the control board is probably bad. If it doesn't blow, Remove the thermostat. Leaving all thermostat wires open check them with an Ohm meter. There should be no continuity between them. Twist all the wires together at one end and ohm them again at the other end. You should have complete continuity on all wires. If the wiring checks out, down power the unit. Double check your wire colors and rewire the control board. With all wires open at the thermostat, turn the power back on. Touch the RED wire to the YELLOW wire. The Condensing unit should come on. Touch the RED wire to the GREEN wire. The fan should come on. Touch the RED wire to the WHITE wire. The heat should come on. Down power the unit. Replace the thermostat. Test unit. If the fuse has lasted ok but blows now it is either wired wrong at the Thermostat or the thermostat is bad. I hope I have helped. NOTE: If you can not understand these instructions. Call a licensed Heating / Air conditioning company. kstfas

Posted on Sep 23, 2007

  • 143 Answers

SOURCE: Wiring compressor

The two terminal cap is only for the new fan motor. Connect the compressor wire back where you found it, on the 3 terminal cap. It's the terminal marked, "herm". The "common" terminal on the 3 terminal cap must still be connected to one side of the 220 power at the contactor. One side of the 220 goes to the common on the compressor. The other side of the 220 goes to the run winding on the compressor AND the common terminal on the 3 terminal capacitor.

Posted on Jul 22, 2008

  • 540 Answers

SOURCE: ac unit central

Sorry, we don't have water cois in our area.

Posted on Aug 21, 2008

  • 3361 Answers

SOURCE: Air Conditioner compressor fan stops, Capacitor wired wrong?

Purple should be on "C".
The fan motor may be destroyed now. Switch the wire and see if it keeps running or not.

Posted on Apr 28, 2009

  • 306 Answers

SOURCE: model#SRCF30U01D. Serial#920-629-3049.

Are the wires going to capacitor correct. You have two sides to the capacitor one side is compressor or herm as stated on top the fan. should have one wire only on fan side then two wires to the common side and one wire to herm side. trace out the wires I'm sure it's electrical and make sure you can see that it does in fact have a dual capacitor. Turn off all electrical supply before even touching this as you are around some big voltage. I do this everyday and I won't even get close unless I pull the safety disconnect on the side of the house. Get back to me and can help further. Ken

Posted on Aug 22, 2009

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

When I switch thermostat to ac position fuse on circuit board blows

There're three main reasons: 1 -you have not enough power in your outlet to run this unit; 2 - the fuse itself is not of enough amperage; 3 - you have a shortcut in your unit.

May 10, 2015 | Heating & Cooling


Troubleshooting Air Conditioner Electrical Problems

Most problems with air conditioners (A/C) are electrical problems, not Freon problems. This is an article containing tips on troubleshooting A/C electrical problems.There are two circuits involved in an air conditioner. There is the line voltage, 120 or 240 Volts Alternating Current (VAC) and the control voltage (24VAC) circuits. The control voltage is used to turn on the line voltage compressor and motors.

In troubleshooting A/C problems you have to determine if the problem is a control circuitry issue or a line voltage issue or component.The first thing you want to do is determine if you have line voltage. You check the breaker at your main fuse box and any fuses at the disconnect box next to the outdoor unit. To check the fuses, turn the power off at the breaker box and remove the fuses. Take a multimeter and place it on the resistance setting. (Rx1) Place one lead on one end of the fuse and the other lead on the opposite end. If the meter arrow goes to zero, the fuse is good. If it stays at infinity (a sign that looks like an 8) it is bad or open. Replace the fuse, as they will blow especially during initial season start-up of the compressor.

If you take your thermostat cover off you will see several small wires. If you take a jumper wire and touch the red wire to the green wire the indoor fan motor should start. This tells you that you have 24VAC control voltage. If it doesn't start, there is a transformer or control voltage wiring problem.To further confirm you have a control voltage problem, remove the access panel to the outdoor unit. You will see a contactor. Use an insulated screwdriver and manually push that contactor in. (Make sure your hand is on the insulated portion of the screwdriver) If the outdoor fan and compressor start, the problem is in the 24VAC control circuitry.

Check for input line voltage at the transformer with a multimeter set on 120 or 240VAC. If you have line voltage, check the output side of the transformer for 24VAC. Trace the problem from the location you have voltage to the place you do not, but should have, using the wire diagram or common sense.


on Aug 03, 2011 | Heating & Cooling

1 Answer


Generally the 24VAC terminals are marked on the furnace board. If it is blowing fuses, check for a short circuit in the thermostat wiring. I have found that the short is usually at the condenser unit where the insulation deteriorated. Many times caused by a dog or cat chewing on the wire. To test, remove the thermostat connections at the control board and power up to see if fuse blows. If it doesn't, you found your problem. Good luck.

May 12, 2014 | Heating & Cooling

1 Answer

My york heat and air unit with emergency heat is blowing 30 amp fuses and sparking at the fuses and contactor when turn main breaker back on. I have replaced contactor, transformer and the compacitor on...

You either have something wired wrong or you have a direct short in the system. Are you starting the A/C or the furnace? If it's the A/C, it could be a shorted compressor, capacitor, fan motor or it's wired wrong.

Oct 30, 2013 | Heating & Cooling

1 Answer

Lowvoltage fuse keeps blowing

the contactor on the condensor if it blows on a call for cool.

Nov 27, 2012 | Gibson Nordyne GR6GD-X24K045C 2 Ton 13...

1 Answer

Thermostat is new but no 24 vac at contactor

If you are handy with meters and electrical work try this.
Somewhere there is a small transformer that supplies the 24volts.
If you trace the wires from the contactor coil back to the big circuit board then the transformer is probably on that board. Make sure you are tracing the COIL wires. If the wires go to a small transformer mounted separately then your in luck. That transformer steps down the voltage to 24 volts used as a "control" voltage for the unit. If you have 24vac output at the transformer, and no 24vac at the contactor then a control or thermostat circuit is open.

Jul 11, 2012 | American Standard Heating & Cooling

1 Answer

My air conditioner will not turn on. No circuits are tripped-I checked.

There may be a fuse inside your unit that is blown. Barring that it sounds like a relay or 24VAC transformer used for control circuitry is not working.

Aug 03, 2011 | Heating & Cooling

1 Answer

It keep blowing up the fuse on pcb ***,y main power supply, we have changed the board twice , first time it worked for a week and second time for 2 hours before blowing up the fuse and probably the board,...

There must be another component which is causing this to happen IE/ The compressor, capacitor, fan, reversing valve coil or perhaps it may just be a damaged wire shorting somewhere. You will hav eto go through each component with an electrical test meter to ascertain which one is faulty... Good luck. Until then , i wouldnt go out and buy another will blow that one as well...

Jul 13, 2011 | LG Heating & Cooling

1 Answer

Air Conditioner was working fine last summer but outside fna not working. Not hearing any sound at all. I can move the fan amanually and it seems fine. There is an electrical box next to the main...

There is a relay in the outside unit. Check for 24 volts a/c at the two wires coming from the furnace. also there may be a mouse nest in the control comartment where the relay is and they tend to chew up wiring insulation and sometimes wires get disconnected .

May 13, 2011 | Carrier 38CKC042 Air Conditioner

Not finding what you are looking for?
Heating & Cooling Logo

Related Topics:

72 people viewed this question

Ask a Question

Usually answered in minutes!

Top Heating & Cooling Experts

Paul Carew

Level 3 Expert

3150 Answers

Dan Webster
Dan Webster

Level 3 Expert

8220 Answers

Tim Whalen

Level 3 Expert

3074 Answers

Are you a Heating and Cooling Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides