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Honeywell S86310U

Daniel_3 Member Posts: 543
edited December 2014 in Thermostats and Controls
Hey guys,

Just switched out my older Honeywell S86310M with the S86310U and was having trouble with the vent damper settings. This all started with no heat in the middle of last night and after checking all the safeties I narrowed it down to the ignition control module that was getting 2.2-2.4 vac at the spark terminal as well as the the 24V terminals. All else was good in the whole system for continuity. This began about a year or two ago where I had posted a few issues with cutouts at the beginning, middle, and end of a heating cycle. I think the module was flaking out over time. This is a Burnham IN7 steamer.

So this controller had no jumper or adapter to override the damper on PC1. It only came with three wire caps, a spark terminal adapter, and a pink terminal (most likely the intended relief of the vent damper). The manual said very little about overriding the damper on the mod so I fussed with it till I got a jump off of the bottom left pin and TW-H.

My question is: Is there a cleaner way or does some adapter exist that would do better than my homemade terminal and 14g black wire?


  • Tim McElwain
    Tim McElwain Member Posts: 4,588
    We only used the S8610 to power the vent dampers for a few years. I believe that was back when the Honeywell Vent Dampers were still around which were a powered close damper during the off cycle and opened with a return spring. We switched to a Polarized sub harness hard wired into the junction box due to difficulties back then with the Effikal two stage open and close type dampers. Every once in a while we still get a call or two saying the installer put in a new electronic S8610U and tried operating the damper plugged into it. When the power was turned on to the control the damper would open and close once and that was it. Never could get a clear answer from Honeywell as to why but a fellow from Effikal (now Field) explained that the control has to sequence properly with the damper because it powers open and proves a position switch and then powers closed to make another position switch. When we stopped plugging the dampers into the ignition module we also began equipping the boilers with S9610M modules without the polarized plug.

    When we get a call like this we advise having the contractor obtain a polarized sub harness which hard wires into the transformer junction box. A little bit of low voltage wiring but worth the effort. I believe the part number for the damper polarized sub harness is # 8136321. If you can find out the serial number of the boiler and the LWCO model number and brand I will be able to provide a wiring diagram of the modification.

    Not familiar with the S86310M or S86310U control numbers.

  • Daniel_3
    Daniel_3 Member Posts: 543

    LWC is a PS-801 or 802
    IN7 is 64956804

    Thanks Tim!
  • JohnNY
    JohnNY Member Posts: 3,149
    He's got too many numbers in there. The poster is talking about the S8610U pictured.
    Contact John "JohnNY" Cataneo, NYC Master Plumber, Lic 1784
    Plumbing in NYC or in NJ.
    Take his class.
  • Tim McElwain
    Tim McElwain Member Posts: 4,588
    Sorry I missed the picture, I will get back to you with an answer.
  • Tim McElwain
    Tim McElwain Member Posts: 4,588
    edited December 2014
    This control is an S8610U ( a Universal Application Ignition Module) and needs to be wired differently than the original S8610M control. The original S8610M did not have a Terminal 7 or TH terminal. The vent damper on this boiler is not plugged into the ignition module. It is probably plugged into the polarized sub harness. The Black jumper wire you have connected into the polarized plug on the control and to the TH terminal is not the way this needs to be wired. The 24v Hot Limit wire that is currently on Terminal 6 (24v)needs to be moved to Terminal 7 (TH). This will energize the control correctly. Terminal 6 (24v) will no longer be used when using the S8610U control. Get rid of the Black jumper currently installed. If the control no longer works then it may have been compromised by the jumper wire that is installed.

    I have a wiring diagram for that boiler if you e-mail me I will send it to you. My e-mail is [email protected]

  • dougfamous
    dougfamous Member Posts: 1
    The new S8610U modules do not require a jumper to operate without the vent damper plugged in, which is why it didn't come shipped with one. Once you've jumpered it, however, you may have blown the little internal fuse and it may not operate again without your jumper in place. (The S8610's are internally fused - once you plug a vent damper into the the plug it will never fire again without the plug attached).