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gesj55 · Oct 11, 2011, 05:48 PM

CNT02536 or White Rodgers 50A61-605-02 Please help I need a new board and now am being told it is obsolete.
Please tell me there is something to replace it besides the 600 dollar kits.
Thanks

JonesHVAC · Oct 11, 2011, 06:56 PM

I need furnace brand and model number please. Thank you

gesj55 · Oct 12, 2011, 03:27 PM

The furnace is a Trane XV90 model TUY080R9V3W1
Some other numbers listed there also are 3391JR07G.
This was installed new in 2003 along with the outdoor ac unit.I read somewhere that Trane extends the warranty up to 10years in this configuration,any truth to that and will the control board be covered?
Thanks, Jay

JonesHVAC · Oct 12, 2011, 04:06 PM

That two-stage furnace was discontinued in 2008 and was replaced by the XV95. In most cases the control board is the same... your best bet is to contact a Trane Dealer in your area to find an OEM replacement. Honeywell makes a universal replacement board as well... to determine which Honeywell board you can use I will also need the part# off the control board. Thank you.

JonesHVAC · Oct 12, 2011, 04:10 PM

Scratch the last request, I see it in the original post.

gesj55 · Oct 12, 2011, 07:00 PM

Thank you for you help If you could find the Honeywell that would be great I am no longer loyal to Trane after this ordeal.
Also I am a electrician and very familiar with HVAC and control wiring, I am sure given the necessary points I could make the Honeywell swap.
Again Thanks so much for the help.
Jay

JonesHVAC · Oct 12, 2011, 07:06 PM

No problem. I will post tomorrow morning with Honeywell part number.

gesj55 · Oct 13, 2011, 05:09 PM

Any luck with the Honeywell replacement?
I have been looking also and I do believe that the White Rodgers universal 2 stage variable speed board will work.
Model 21V51U-843 Universal Two-stage HSI Integrated Furnace Control Kit
Do you have any knowledge of these boards?

JonesHVAC · Oct 15, 2011, 06:47 AM

Sorry friend has been a long couple of days...

Yes that control board will work, you need to make sure the ignitor is switched out as well... should be provided with the board. Let me know if you need me to ship to you, I can get it for $200+tax. You may be able to find it cheaper online but make sure it is complete package.

gesj55 · Oct 15, 2011, 08:10 AM

Thanks for your help.
I did purchase the board locally through the company I work for.
I have been studying the wiring diagrams and the only thing I see that is really any different are two wires which will not be needed to the inductor motor.
They are the RPM/SOA(safe operating area) and the 13VDC line which I believe powers that signal.
The 1st and second stage pressure switches are used differently on the new board and I can wire as such, however the var speed inductor may be looking for those signals as well. Should I find that the inductor needs those signals I can wire them in also.
I will post when I'm done and let you know how it worked out.
Thanks, Again

JonesHVAC · Oct 15, 2011, 08:25 AM

Glad I could be of help to you!

gesj55 · Oct 18, 2011, 06:21 PM

I am almost completer with the furnace control re-configuration. I did have to order a new 2 speed draft inducer motor as the old variable speed would not work with the White Rodgers 50V51-843 board.
However I do have a question on motor dip switch configuration for the blower.
The new board give me two switches SW3 and SW4 which they call motor optimization, and they tell me to exactly match the old board SW3 and SW4 settings. However there are no such switches on the old 50A61-605 board.
Does anyone have a clue how these switches should be set? The motor controller in the furnace is a MOD00836.
I believe that SW3-1&2 Apply to cool and have 4 choices No signal, Positive Half Wave, Neg Half Wave, and Full Wave.
SW3-3&4 apply to adjust with the same choices as above.
Sw4-1&2 apply to Delay, with the same choices.
Sw4-3&4 apply to Heat, with the same choices.
All help would be appreciated.
Thanks,

JonesHVAC · Oct 18, 2011, 08:28 PM

The instructions for the new board don't have the settings listed for your furnace? There should be a page dedicated to telling you how to set the dip switches...

JonesHVAC · Oct 18, 2011, 08:37 PM

You may want to take that stuff back... I just found this: http://www.ebay.com/itm/Trane-CNT025...-/370539440446

gesj55 · Oct 20, 2011, 09:41 AM

The project from hell is complete and I have heat today.
I did change out the board to the 50V51-843, and changed out the draft inducer to 2 speed along with some re-wiring everything functions fine.
I was un-sure of the motor optimization dip switch settings, any hints in that area?
Thanks for all the help.

JonesHVAC · Oct 20, 2011, 10:23 AM

I would leave them set at their default location being that those were not part of the initial board. Glad to hear you have heat and a job well done on your part! :)