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Install manual says to use 3- 16AWG 'polar' wires to connect condensor to indoor unit & 2-22AWG 'non-polar' wires for control. What is'polar' wire?

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Polar refers to polarity. When dealing with the power you have to use color coded wire usually red, black, and white. This is so you don't incorrectly hook it up and cause a short. On the control it does not matter if you use coded wire. It is just to complete a 2 wire sine circuit for a thermostat. Hope that helps.

Posted on Jul 01, 2009


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AC will not turn off unless I turn the breaker off. The furnace is also running non-stop, I have to pull the fuse to stop it.

You should be able to pull fuse and that will stop the indoor and outdoor unit. Also try this.

Turn off all line voltage at breaker panel to yoir house. At your air handler there should be a terminal block where most of the control wires connect. This will(should) have R W Y G C letters, and maybe more. Mark what wires go where and don't get them confused. Take pictures. What ever you need to do to put wires back where you removed them from. Remove all control wires at the terminal block but only the one we connect when we install the unit. Usually brown insulated with colored wires inside. Should be 2 brown ones. 1 from your tstat and 1 that communicates with your o.d. unit. Turn on all the breakers and see if either unit starts with no control wires connected to it. If it does not start, chances are you have a shorted thermostat or shorted control wires. If either unit starts with no controls, then you know its inside one of the units. A fault at a circuit board or shorted control wires. A short in a system can tedious but can be isolated.

Jun 23, 2015 | Heating & Cooling

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How to troubleshoot thermostat wiring?

I'm not sure if the thermostat is wired correctly. First, the thermostat is wired directly to the outdoor unit (compressor/condenser unit). It is NOT directly connected to the indoor unit. It connects to a low voltage control panel in the outdoor unit that sends a signal to your indoor fan/evaporator. This wire is called the fan relay switch and physically runs between the low voltage controls of the indoor and outdoor units. If the fan relay is bad it's possible that the unit runs continuously. To prevent destroying your outdoor unit there is a safety feature that prevents the indoor fan from shutting down while the outdoor unit is running. If the indoor fan did shut down while the outdoor unit was running than you would slug your compressor. That is, your compressor normally sees refrigerant gas but is instead seeing refrigerant liquid. That would not be good since this scenario would destroy your compressor. It sounds like a faulty fan relay. The actual contactor portion of the relay is in the outdoor unit.

Aug 22, 2014 | Honeywell Electronic Programmable...

1 Answer

Alarm light flashing nature

Sounds like a polarity issue. Make sure the indoor & outdoor units control voltage that ties each other together are on the right terminals. If they are, then reverse the control circuit wires.

Dec 05, 2013 | Samsung Heating & Cooling

1 Answer

Daikin split system air con dead

Split system Air conditioners are very often on two or more separate breakers, with a control voltage (24vac commonly) connecting their operation. the condensor unit and out-door fan generally on a 220 vc 'paired' breaker, possibly a quick disconnect near the unit with fuses inside, or an independant breaker pair, and the evaporator unit with INDOOR fan on a 110 or 220 vac breaker.

switch the fan to 'ON' at the thermostat... this is the midpoint of the system electrically. If the fan comes on check for voltage at the condensor unit. a check to see if the thermostat is the problem... remove the thermostat and connect the red, green and either the white or yellow wires (not both) if you chose white you should have heat...yellow AC...

most split system AC have a small buss fuse on the control circuit board of the indoor unit. looks like a glass tube with metal caps held by metal clips. In 40+ yrs experience I have found it is more likely one or both of the 30 amp buss fuses near the outdoor unit (replace both even if one is still ok) or a 30 amp breaker in the quick disconnect box.
In many systems the control voltage to the thermostat derives from a transformer in the outdoor unit... it could be as simple as a broken wire. Without a full diagnostic, a complete description of the unit ( AC or heat pump, etc) this is all speculation

Nov 19, 2013 | Heating & Cooling

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Have a goodman central air unit, non heat pump. keeps smoking transformers, on the inside unit, replaced fan capacitor and transformer as the old transformer was smoked as well. But to no avail the new...

There is a short in the control wiring that needs to be tracked down. Ohm the wiring to the low voltage controls, ie thermostat wiring and thermostat. Try disconnecting the thermostat wires to rule out the problem in the control wiring to the thermostat or thermostat itself, then install a new transformer without connecting the thermostat wiring, jump the red and green wire at the unit low voltage connections to test blower, and then add yellow for compressor, should be no more than 3 amps on control side wiring with A/C on.
If the problems still exists without the thermostat wiring connected then there is a problem in the wiring in the unit or control board itself.

Aug 24, 2011 | Heating & Cooling

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The thermostat clicks but nothing else happens, no a/c will come out or no heat [I tried both]

(I have this model at my home). If you switch it over to emergency heat and nothing comes out then check the breakers behind the panel for the air handler (inside unit)
There may be other issues, mine had a sequencer which had come apart. The newer
sequencers have a retainer clip to prevent this. It is located under the galvanized cover inside the indoor unit next to the transformer.

Also check the breakers at the main panel (there should be two double breakers, one should be a 20 to 25 amp for the outside unit and the other should be around 70 amps for the indoor unit). Fully reset them after performing checks described later. .
If your outdoor condensor compressor is failing (as mine did), it will trip the smaller breaker, if your indoor unit has a short or other problem it will trip either the 50 or the 70 amp breaker. Make sure you turn off all breakers before inspecting.

One last thought, if your thermostat has battery backup and the transformer has failed, you will still hear the click but nothing will operate
since the 24 volt transformer operates both the indoor and outdoor units.
It is located under the galvanized cover inside the indoor unit.
(I would suspect this if all else appears normal with no breakers tripped). A universal transformer is around 8 to 12 dollars make sure to use the 240 volt wire and the COM
when installing it. (there are several wires for various input voltages on the primary).
they are available at any HVAC parts store. Power off to all sources before repairs.

Aug 10, 2011 | Intertherm Heating & Cooling

1 Answer

On my central air inside unit I have a red light flashing constantly.(reverse polarity) How do I do that....It seems to be a Goodman.

Hi, to reverse polarity means your electric power coming into the indoor unit is wired backward is all. It should be 120 volts coming in, so find where your power cord wires come in to the unit, a black and a white, they should plug into the board, and just switch them around, nothing to it!! Unplug the unit first, or shut off the breaker. This will solve your problem, as the 2- wires are just reversed.
A/C, & Heating contractor

Apr 24, 2011 | Heating & Cooling

1 Answer

I have a samsung silver nano...the indoor unit & the outdoor unit fans are running...but there is absolutely no cooling. Any idea why?

  • Ensure Air Filter is clean - clean as necessary
  • Ensure Evaporator coil is clean - clean as necessary
  • Ensure Condensor coil is clean - clean as necessary
  • Inspect all wiring inside the unit for any loose or damaged connections - correct as necessary
There could be a failed compressor relay, run capacitor, or compressor motor/valves. Of course, it could also have lost it's refrigerant charge.

Without being onsite with toolbox in hand, I hope you find this information to be very helpful moving forward. :-)

May 10, 2010 | Samsung AW0503B Air Conditioner

1 Answer

Indoor unit freezing up


Mar 09, 2010 | Heating & Cooling

1 Answer

System will not start up.

This is a signal fault between the indoor and outdoor first make sure the dip switches are set start with the unit closest to the condensor set as unit 1 then next unit as 2 and so on the dip switches are inside the indoor unit on the pc board if you check the manual it will tell you which swithes to set, if this wasnt done when the units where installed they would have never worked i would also check the signal wiring between the wallmount and the splitter box / bc box and make sure there isnt a loose connection when you have ruled this out id say more than likely it is a faulty indoor board on the wallmounted unt

Jan 27, 2009 | Fujitsu 24C1 Air Conditioner

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