Trane XL80 Controller Problem or T-Stat
Results 1 to 7 of 7
  1. #1
    Join Date
    Feb 2006
    Posts
    3
    I have a 6 year old Trane XL80 gas furnace that recently has been shutting down (typically when recovering from 65 up to 70 in morning or afternoon). This is an intermittent problem that I would like to get some information on before I have a HVAC contractor come out to tell me it's working okay. The LED on the White Rodgers control (50A51-495, CNT2184) is continuous on indicating "replace control". However, if I turn the switch on the t-stat from heat to off position, the fan immediatly restarts (I keep the fan in ON mode) and the furnace lights. The frequency of this event has increased over the past few days. The unit quit again this morning and I disconnected the t-stat. When I disconnected the t-stat, the LED on the furnace control went from continuous on to blinking "normal mode". Is the problem the controller or the t-stat? If the problem is the t-stat, why does the control LED indicate replace control? Is there any other information that I could get prior to having a contractor come to make any repiars? Can there be an intermittent problem with the control that cycling the t-stat switch from heat - off - heat would reset? Thanks

  2. #2
    Join Date
    Jun 2000
    Location
    N. W., IN
    Posts
    1,017
    Go ahead and make the call for a check-up. When you power off and on or switch off then heat you reset the control but you allready know this is a temporary fix. Get it checked out before it goes out completely which only happens at 2am and 2 below zero.

  3. #3
    Join Date
    Oct 2005
    Posts
    922

    Hmm Call them

    I don’t think he will tell you everything is ok if it is an indication of replace controller.

  4. #4
    Join Date
    Feb 2006
    Posts
    3
    I had a contractor listed by Trane come look at the system. The controller was burned out in the circuitry related to the second stage heat cycle (nice scorched area around 4 resistors). This leads me to the following observations: Why would a solid state control board burn out? Is there a design flaw in these controllers? Are they designed to burn out? Are they designed to fail in order to protect other components?

    Unfortunately, I expect I'll be paying for this repair again at some point in the future since the replacement controller was the same part number as the one that burned out (I am making the assumption that adjustments to the design specifications have not been made by Trane or White Rodgers).

    Do companies like Trane have replacement controllers that are more reliable or do they have an inventory of parts that they will use until they are gone? I guess the difficulty here is when you have parts with a 6 to 8 year life cycle, it takes a long time to determine that the part may have a problem and the cost of engineering a replacement may not be worth it for a part that lasts for 6 years. Unfortunately, since I am not a contractor, the local Trane parts store will not tell me if there is a more suitable replacment. I guess I should assume that if Trane was recommending a different part, that they would communiate this information to a Trane authorized contractor.

    Maybe I am being a cranky, cynical, customer with expectations that are too high. The most frustrating part is that when I bought the Trane, I was expecting to not have problems (especially failing circuit boards). I would expect to eventually have mehanical problems with valves, motors, etc.

    In any case, I am happy that I have heat before the big weekend cool down.

  5. #5
    Join Date
    May 2000
    Location
    Indianapolis, IN, USA
    Posts
    33,884
    Used to be we would never replace a White-Rodgers IFC. But since the production switch to Mexico, they've been more trouble. The worst is the Intell-ignition board but even the old silicon carbide board like the 2184 have been more problems than they used to. Unfortunately that's the way of the industry.

  6. #6
    Join Date
    Feb 2006
    Posts
    3
    Is the issue here the quality of the assembled board or the quality of the design and components used for the board. The quality of the soldering in the old controller looks okay. How many furnace manufacturers have problems with control boards?
    Are there furnace manufacturers that have a better track record with their designs? What caught my attention today was when the contractor said he had replaced control boards in 3 Trane XL80 furnaces this week.

    I will do alot more research before I buy my next furnace. I don't know if it will be a Trane. Who knows, if the way of the industry is towards more problems as BaldLoonie suggested, maybe there will be a more reliable designs from a foreign manufacturer like LG.

  7. #7
    Join Date
    Jul 2002
    Posts
    962
    My educated guess would be the quality of the design and components used. Most design problems thru feed back from the field, are improved on for future stock. A small percentage of the problems are related to defects in the parts themselves. This is due to mass production problems.

    All manufacturers face the same problems of mass production. They could make them more reliable but then we couldn't afford the cost it would take to achieve that goal.

    The scorched area around the resisters means nothing. It could be from heat around resister discoloring board. How did you determine that was the 2nd stage heat cycle?

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Comfortech Show Promo Image

Related Forums

Plumbing Talks | Contractor Magazine
Forums | Electrical Construction & Maintenance (EC&M) Magazine
Comfortech365 Virtual Event