Hi,

I just purchased a new control board and the istallation "seemed" very straight forward, i.e. hooking up the various wires from the old board to the new one. However, all I have been able to accomplish is to get a twinning error code, i.e. a rapid red blinking of the diagnostic light. Any idea of how that could possibly be the case, since I do not have two furnaces [that I am trying to run in parallel]?

Thank you in advance for any assistance,

David

What brand of furnace? Some have a break off tab for twinning may have gotten broken in shipping. Also double check wiring polarity mainly. Hope this helps.

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Originally Posted by td26

what brand of furnace? Some have a break off tab for twinning may have gotten broken in shipping. Also double check wiring polarity mainly. hope this helps.

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Hi TD,

Thank you for replying.

My brand is Coleman [gas].

I don't believe there is a "break off tab" for twinning. There is a metal "male" receptacle on the board labeled "Twin" but of course I am not using it.

As far as polarity, I have double, triple and quadruple checked the wiring to make sure all wires are running to their respective receptacles [compared from the original board].

Needless to say, the Twinning error code is a real mystery!

Thank you again,

David

Are there any DIP switches on the board? Does the unit service label offer any clues to the twinning configuration?

You probably have a 24 volt problem. Reverse the 24 volt secondary wires and this will change the polarity. That should do the trick. The newer boards are really sensitive to reverse polarity. Also make sure the ground wire is attached from the main electric panel all the way to the furnace ground area. That is another problem for the newer furnaces/circuit boards.

See doc.

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Originally Posted by KC13

Are there any DIP switches on the board? Does the unit service label offer any clues to the twinning configuration?

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Hi KC,

The original board has two dip switches for the Blower Off Delay. The new board (they are both Source 1) uses a pin instead [but with the same options, i.e. 30, 60, 120, 180]. The new board also has a pin setup for Continuous Fan Speed [Lo Cool, Heat, Hi Cool] which I could not find on the old board. It came with the pin in the Hi Cool slot, but I've experimented with putting it in the Heat slot (we have no air conditioner), but with no change in results.

The Installation Manual for the furnace has a paragraph labeled TWINNING, along with a diagram showing a wire running between the two "TWIN" receptacles/plugs. The paragraph says [in part], "If two furnaces are to be twinned using a single wall thermostat, connect an isolation relay as shown in Figure 12 below." Since I have only one furnace, I couldn't see anything to do with this information.

All help/suggestions appreciated!

Thank you,

David

Quote:

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Originally Posted by hvac1000

You probably have a 24 volt problem. Reverse the 24 volt secondary wires and this will change the polarity. That should do the trick. The newer boards are really sensitive to reverse polarity. Also make sure the ground wire is attached from the main electric panel all the way to the furnace ground area. That is another problem for the newer furnaces/circuit boards.

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Hi hvac1000,

I will try both of your suggestions. I will have to wait for some help from a friend, on this one, but will report back on my results.

Thank you so much for your input!

Sincerely,

David

See rapid red in my post link. This is from the factory manual. This will keep you from spinning your wheels.

No problem. We ran into this proble at the university about 4 or 5 years ago. Now most of the manufactures that use this kind of board post this info as the fix. I am surprised the manufacturer of the board did not rewrite the chip code to take care of this problem.

Quote:

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Originally Posted by hvac1000

You probably have a 24 volt problem. Reverse the 24 volt secondary wires and this will change the polarity. That should do the trick. The newer boards are really sensitive to reverse polarity. Also make sure the ground wire is attached from the main electric panel all the way to the furnace ground area. That is another problem for the newer furnaces/circuit boards.

See doc.

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Problem solved! I want to thank td26, KC13 and hvac1000 for their kind generosity in responding. Hvac1000, you're a genius!

Much thanks again,

David

Thanks for the compliment. I try to stay on top of things in this industry but I have to admit I am getting older. KC13 is also a sharp Technician when it comes to HVAC and he has answers that I do not have for many items. Glad you got it going.

What is a 24 volt secondary power? You got any sort of diagram or something? I have this exact issue but I did not replace my control board recently (I did last winter)

In my case I fired up the furnace a week or two ago to make sure it would work OK when the time came and it worked just fine. Now I turn it on and the blower runs for maybe 10 seconds then the LED starts flashing rapidly indicating reverse polarity according to the sticker on the door. The polarity on the 110 coming in is NOT reversed. I need some help here. Last issue I had was with my cooling and I paid a guy 100 bucks to come in and throw the wrong but working transformer in and FLIP OFF THE GAS VALVE (probably assuring he could come back when winter got here) Im not going that route again.

This is frustrating.. this furnace and air conditioner are only 5 years old and I have already had 1 major repair and 1 control board and 1 minor repair.

Hi I have been reading all your answers & I have the same problem, I have a Luxaire. Reversing the polarity ? What wires is this & where ? I had a service tech out & he told me I need a new board.
Thanks
Matt