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Rheem gas furn codes

TBK1TBK1 Member Posts: 14
start off by saying, first time poster, and new to the feild! Be easy on me! have a RGTA series 90 % gas furnace that wasnt the best installed, fly by night that went out of bus, installed in 95 as propane, then converted in 98 to natural, 2 years ago blew the control board , and now appears to have blown another. no heat, no ignition, idf and draft motor run non stop as soon as power applied, no thermostat control, honeywell board has been rplaced by a UNIVERSAL brand UTEC board. PWR light comes on steady, OK light flashes 3 times, flame light never comes on, have 24 volts from trans to board, inline fuse was bypassed and hotwired (DA) am replacing the fuse. have checked most switches but could use some data on this, none available.
Thanks for any help


  • Rheem Furnace

    These furnaces originally used a Honeywell S9201 series Integrated Furnace Control. What Model number UTEC board does it now have? I need that info so I can help you. Was the UTEC replacement a factory authorized change?

    The fact that Induced Draft Blower is coming on says that part of the board is okay. Does the system blower also run with the IDF? If it does how long does it run? Does it eventually shut off then come back on? If it does that is the "Self Healing" feature of the board. It will do that if the board sees any open limits, hi-limit, aux limit, flame roll out, blocked vent switch (spill switch).

    The "Okay" light flashing usually is related to "twinning" problems. Are there two furnaces hooked together? There may be other code related to the flashing but my Rheem info does not show any.

    The fact that the "universal" UTEC board has worked for two years says it must have been okay, or have there been ongoing problems?

    Have you replaced the fuse yet? That fuse is typically a slo-blow fuse rated at 2 amps.

    There is a Rheem web site you might try click on air conditioning to get to furnaces.

    Get me some more info and I will try to help you. It does however sound like you may have a defective board.
  • WayneWayne Member Posts: 62

    I understand both the inducer fan motor and the indoor blower fan are operating. The indoor fan motor never shuts off. The control board is working properly. This indicates the system is off on high limit or a bad connection in the limit circuit. Replace the fuse with the correct short one. You may have to go to a RUUD or Rheem or Comfort King dealer to get one.

    Turn the electrical power off. Depress each one of the high limit switches. They are located above the burner manifold with red wires. All the switches are in series, so check each one. They depress very little so it is hard to check if one is open. Check the balance of the wiring and the high limit is on the left side with the same red wires to the limit.

    Turn the power on to check the furnace. If the limit siwtch was open, new the furnace should start.

    Now you need to have a quailfied technician/service company perform a tune up, This should include measuring and setting the manifold gas pressure and temperaure rise across the heat exchanger.

    There is a good possiblity the heat heat exchanger is sooted up internally and willl need to be replaced. Should be under warranty.

  • Curious why

    "depress limit switches" not quite sure what you mean??? Are you maybe talking about the little red buttons on the switches???

    Why not check continuity on the switches or use a multimeter grounded to "C" terminal and systematically check each component Starting at the transformer and working toward the gas valve.

    There is also the possibiblity that the pressure switch is not making. I would however reserve judgement until we get more info on the UTECC board.

    I am also curious as to your statement that the heat exchanger is sooted up, I guess that relates to the resetting of the red buttons on the flame roll out switches due to blockage causing the flame to roll out and trip the switches, is this correct??

    Last of all why would you replace a sooted up heat exchanger, why not clean it and then do a camera test on it after cleaning. Again just curious.

  • LarryLarry Member Posts: 86
    My 02

    Not sure what the three "OK" flashes indicate. Basic codes should be on the control or in the literature. Already mentioned is the press switch may not be closing. Could be a bad press. switch or more likely a clogged/restricted press. hose barb, restriction in the inlet or outlet vent pipe, or inducer not moving enough air. Continuity tests through the switches would indicate their integrity. Also, if the board sees press switch contacts closed at the start of a call for heat, it would sense stuck closed contacts and not allow the burner to come on. Not sure if inducer would run in this case, though. Last but not least, hot surface ignitor may be cooked but usually the valve will dump gas momentarily and then cut off due to failure to prove flame.

    After finding the problem, don't be a stranger. Post what you found.

    Good luck,

  • Forgot our manners

    tbk WELCOME TO THE WALL. You will find many who are here to help you. This is a great site and remember all of us were new once. Let me see now can I remember back that far.
  • Glenn HarrisonGlenn Harrison Member Posts: 405
    Just checked my Rheem book,

    and looking at the book, and more specifically the diagnostic flow chart, I see that if you have the power light on, and the O.K. light is not on (flashing in your case) it is a defective board. The only exception to this as Timmie said is if this furnace is "Twinned" to another furnace, and if they are not "Twinned" together properly, but this does not sound like the case.

    Glenn Harrison, Residential Service Techician

    Althoff Industries, Crystal Lake, Illinois

    Althoff Industies Link
  • TBK1TBK1 Member Posts: 14

    gentlemen, thank u for ur inputs. i appreciate u trying to help. ok let me try to clear some things up.this a a 90 plus, RGTA-12erajs, in a craw space in the horizontal position. the fuse and holder ,i'm guessing, have been gone since day one, am going to replace it.120,000 btu unit. The pressure switch checks good and appears to be funtining correctly, didnt know about the switches on the linits, i'll be sure to check them. the UTEC board i am guessing was not authorized but just done , who knows why, availability ???, it did have HW board, i have the old one, r-14 and r-15 below the lights are positively burnt on it. the utec board is a 1012-920A-I, no literature for either board or the entire unit, hensce the questions. this house is out rural so with the missing fuse and power spikes that are associated with the rural setting, is why it is leading me to the board. it took the fly by night installers 2 months to get this to work, so no telling what has been done, the unit is a single unit with a/c attached not a twin unit.the inf comes on immediately with the draft motor and neither ever shut off, with the thermo disconnected it still acts the same, 24volt trans appears to be working ok. all connections are ok. Going back out mid week with a board if i can find one locally just in case. Warm climate down here and home owner not in a hurry!, actually wants it fixed for the a/c side before it gets to hot, thanks!
  • John MillsJohn Mills Member Posts: 221
    3 blinks

    means limit or rollout. Ohm out the main insertion limit. If OK, then check the rollouts up in the burner compartment. Those are manual reset. If you find one tripped and resetting it gets the fire on, watch the fire carefully to see if there is a cause. Pretty rare for them to trip. This is a big furnace, does it have the duct system and home heat loss to support it? Did you check to see if orifices and GV spring have been changed back to natural?

    I don't believe you have a board problem. Sounds like it is behaving as designed. If a limit is open, the inducer and blower are to come on.

    We've sold these for 10 years, my Sister got one of the test furnaces. They are one of the more reliable 90s I've seen IF INSTALLED RIGHT!!!

    If you want further info on this furnace, I can e-mail you the pdf files from Rheem's dealer website.
  • Glenn HarrisonGlenn Harrison Member Posts: 405
    John, may I ask a favor of you?

    WHERE did you get the information that three blinks means an open limit??? I looked in two different Rheem books covering that model and nowhere does it say that three blinks = open limit. As I said above, it only shows that the only time the O.K. light will blink is if it is not twinned properly. I even went to the Honeywell tech lit site and there lit for the S9201 board shows the same info. PLEASE educate me, as I have a number of Rheem units out there installed by others using these Honeywell and UTEC boards, and if I am missing something, I would like to know. Please e-mail me with any files, or secret websites that are availble with detailed Rheem/Ruud info.

    Thank you very much in advance

    Glenn Harrison, Residential Service Techician

    Althoff Industries, Crystal Lake, Illinois

    Althoff Industies Link
  • Glenn Interesting you should ask

    I was doing the same thing and agree with you the okay light only flashes with a twinning problem.

    I looked in all of my notes and even checked the engineering specs I have for the Honeywell S9201 and UTECH 1012-920 and could not find anything.

    I am also interested John in any thing you have as I teach using the Ruud/Rheem manual to all of my classes. I would be interested in any factory bulletins you my have that shed some light on this.

    I am also interested in knowing if that UTECH board is a factory authorized replacement for the S9201 Honeywell board. I know they are very similar, and the Ruud/Rheem instructions I have list them together but my experience with trying to replace one with the other has not been good.
  • Glenn HarrisonGlenn Harrison Member Posts: 405
    Darn, Timmie

    I was kind of hoping you would come up with that info:)

    I am kind of mad at myself as I have been working with these boards for 10 years and been to Rheem classes and have never been told about these light providing fault codes.

    As far as the UTEC board goes, from what I have seen on a replacement basis, Rheem seems to either switch back and forth, or just provide either of these boards, but they are both listed as approved boards in the book I have, in fact there are wiring diagrams for both boards in my books, so the UTEC board he has would be fine, excep of course for the burned resistors he described below.

    Glenn Harrison, Residential Service Techician

    Althoff Industries, Crystal Lake, Illinois

    Althoff Industies Link
  • John MillsJohn Mills Member Posts: 221
    Rheem fault codes

    General Topics

    Standard Furnace Diagnostic Codes

    Does not include Modulating, LXE, or Two Stage furnaces.

    1 Blink = Soft Lockout (1 hour)

    2 Blinks = Pressure Switch Failure (remains open)

    3 Blinks = Limit Switch Open

    4 Blinks = Pressure Switch Failure (remains closed)

    5 Blinks = Twinning Circuit Failure *

    *Only applies to boards with twinning feature.

    ** The National Service Department has found that the 5 Blink code can occur in some situations when an electronic thermostat is used.

    Anything you want to know is at

    You have to sign up, I would think any contractor should be able to get a password. We've sold Rheem/Ruud/WeatherKing for 15 years so had no trouble.

    Rheem uses boards from UTEC, Honeywell & Johnson. They all seem to interchange just fine. The first 4 characters of the serial # tells what the original control setup was.
  • Glenn HarrisonGlenn Harrison Member Posts: 405
    Thanks a million (at least), John

    That helps alot. I'll get signed up to that site as soon as I get our distributor info.

    Thanks for helping me to live up to my motto of, "Learn something new every day", even on my day off. :)
  • John Mills, thanks

    for that info.

    I am not a contractor, can I still sign up?

    My function is training and I have found that a lot of companies will not give information to trainers unless they work directly for their company.

    I do have another question, why isn't this info in the Ruud/Rheem training books or are mine out of date? The books I have OLCSM-011-02 revised PS12-94 and OLCSM-014-1 revised PS09-94 I do have both Integrated boards in the book but not those codes.???
  • John MillsJohn Mills Member Posts: 221
    Try to sign up

    They aren't going to verify that you are a contractor. You'll need to know the name of the local Rheem or Ruud distributor.

    I don't know why this isn't in the books. I just remembered what it was so didn't look it up until later.
  • TBK1TBK1 Member Posts: 14

    john, thanks, i got in to the site and was able to extract everything i needed, thanks to all who have replied, ill post upon fix to let all know
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