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Weil-McLain wm97 return lockout?

JakeMillerJakeMiller Member Posts: 17

I have a Weil-McLain WM97+ (110 BTU,) with 3 zones. Only two zones are operational at this time.

When the T-Stat is calling, the boiler kicks on and during the cycle in the beginning boiler runs for a bit, and than LOCK OUT with red background. The trouble shows "58F RETURN LOCKOUT". Than it stays for a few minutes and starts on it's on again.

- My question is it resetting over and over again on it's own... or something else?
- My other question is what is wrong here and what I can do to fix it...

Supply is set for: 175F

plz help...


  • lchmblchmb Member Posts: 2,983
    Is this a new install? Need to check your sensor connections to make sure everything is tight. Then make sure the boiler is piped properly...
  • DanscrewDanscrew Member Posts: 118
    Did this just happen ? Check the conections on the sensors on the side of the Heat Exchanger they may have come loose? then check your piping was the boiler piped correctly ? go to pg 106 of the manual Troubleshooting
  • njtommynjtommy Member Posts: 1,105
    Is the fault intermittent or all the time? In the Manuel there should be a temp to resistance chart. If you have a multi meter you can ohm out the senser and see if it's reading currectly.
  • JakeMillerJakeMiller Member Posts: 17
    edited December 2015
    @lchmb ... it is a new install....

    @Danscrew ... I've checked all the connections all are nice tight, and the boiler is piped accordingly to the book. see pic plz / I did see the page 106 and I can't seem to find the issue.

    @njtommy I did see the chart... and I had the temperature set at 175F for target... which I just changed to 165F... This happens every time any of the zones are calling for heat.

    Pic is attached... I know it;s not the prettiest piping... but did what I could with the space...

    I cleaned up the pic a lil bit, so the its not too much clutter...

    error reads" SUPPLY 58F > RETURN "
  • njtommynjtommy Member Posts: 1,105
    It does not look like you have a primary loop piping/ secondary loop. If your not mixing your return/ supply with a primary loop your return will enter the boiler way too cold and give you this fault.
  • DanscrewDanscrew Member Posts: 118
    Take a pic of the front of the boiler with the cover off Like NJTom said is the boiler setup Primary/Secondary? On that boiler the piping is internal for Pri/Sec there is a ball valve to turn on and start the internal circulator from the keypad
  • Boiler wrestlerBoiler wrestler Member Posts: 43
    Are you sure you have flow? I suspect you don't. I can't see the top of the boiler so I'm not sure how you vented it as it appears higher than the air separator.
  • DanscrewDanscrew Member Posts: 118
    Do you have a system circulator? or is it using the internal?
  • JakeMillerJakeMiller Member Posts: 17
    @njtommy - no I didn't add that, actually by it has a built in option in the boiler for mixing... so I figured wouldn't need it... but maybe i was wrong - Inside the valve is closed, because according to the manual it should be closed if using the boiler Cir to circulate water... which I am.

    @Danscrew - pic is attached... it shows the internal ball valve... mine is closed , even though the pic shows it open... when I did have it open, I wasn't circulating the hot water to any of the zones and it would lock out 2 minutes or less....

    @Boiler wrestler - I do have the flow, on the top I just have to supply and return coming down to the left as pictured... and than the vent....

    @Danscrew - currently I am using the boiler circulator to do it all, I know I should have at least one pump, but I was cheap and didn't have the room... I guess now I am paying for it...

  • DanscrewDanscrew Member Posts: 118
    Going by the pic the valve is open (handle up and down is open) meaning it is setup for Primary/Secondary operation. Unless someone removed the valve handle and but it back on ? Go into your pump setting and switch it to high not sure what speed you are on now? The internal pump is a 3 speed circulator try that and see what happens if that works your problem is flow the internal pump is for running in Pri/Sec and your system pump would be to circulate thru all your Rads floor or whatever you have.
  • JakeMillerJakeMiller Member Posts: 17

    Currently the valve is closed... side to side... this pic is older, from another unit, but same internal parts.... when I originally had it open, the boiler was locking out faster than it is now, plus it wouldn't even get my cast iron baseboards hot.... on any of the zones... meaning the water wasn't moving much... it was just sucking in from the supply loop within the boiler i guess.

    currently with the valve closed the baseboards do get hot, because the boiler keeps resetting automatically after it locks out and the water does circulates.
  • DanscrewDanscrew Member Posts: 118
    Try speeding up the circulator to High ? are you familiar with doing that ?
  • JakeMillerJakeMiller Member Posts: 17
    Yes, did that too... makes it lock up faster... lol
  • DanscrewDanscrew Member Posts: 118
    You may Have to add a circulator for the system and run the boiler circulator in low and the boiler operating in primary /Secondary mode ( Design conditions) to get best results what are you heating baseboard? your supply is set way High for a condensing boiler? How long have you had it on- line ? Where are you located?
  • JakeMillerJakeMiller Member Posts: 17

    It's cast iron baseboard - normally set for 180F, I have it at 165F.
    I guess when it's nice out I'll re-do all the piping and add cirs...
    I live in South Jersey area.

  • DanscrewDanscrew Member Posts: 118
    What's your email we can talk I'm running the same Boiler pretty familiar with its operation . Dan
  • njtommynjtommy Member Posts: 1,105
    @JakeMiller where at in south jersey?
  • JakeMillerJakeMiller Member Posts: 17
    Atlantic City, NJ.
  • njtommynjtommy Member Posts: 1,105
    I'm not far from you. I'm on the other side of Hammoton. It really wouldn't be hard to add a circ to the system. At the same time I would recommend doing away with the air scoop and installing a micro bubble/ air seperator.
  • Rich_49Rich_49 Member Posts: 2,540
    Where does that supply pipe go after the 3 zones are fed ? How many feet of baseboard are on each zone ? How many 90*s do you have within the system ? How did you purge this ? What pump is onboard in that boiler ?

    You should have Tommy come over and get you straightened otu . You cant wait for it to get nice , you may freeze to death by then , the time is now .
    You didn't get what you didn't pay for and it will never be what you thought it would .
    Langans Plumbing & Heating LLC
    Serving most of New Jersey, Eastern Pa .
    Consultation, Design & Installation anywhere
    Rich McGrath 732-581-3833
  • JakeMillerJakeMiller Member Posts: 17
    @njtommy - sounds good... I'll keep you in mind... the money is tight right now for me, which is why I kind of did the work my self, not a plumber but tried my best...

    @Rich - the supply doesn't go anywhere else.. I had some extra drain valve so I hooked it up for easy draining from both sides... and remove mess from the manifold....
    roughly - 36 ft on top floor, and roughly 30ft on the bottom floor, 3rd zone is not really all that important but will be hooked up for laundry room, maybe 5 to 7 ft of baseboard.

  • kcoppkcopp Member Posts: 3,463
    You really need to do a primary secondary set up...
    The fact you used pex tubing and the crimp pex 90 really creates a pressure drop. Its way too much for the boiler pump to do on its own.
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