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Williamson-Thermoflo GWA 105 problems

WardWeathersWardWeathers Posts: 9Member
edited January 2018 in Gas Heating
I have done a search here and done as much reading as I can, and am a bit stuck/unsure how to proceed.
About 5 years ago, a Williamson-Thermoflo GWA 105 boiler was installed for this 1940s vintage 1000 square foot house with hot water baseboard. The house is poorly insulated. Prior to conversion to gas, the old oil boiler was able to heat the house. The unit was heating contractor installed.

The "new" gas system performs ok when the outside temperatures aren't too bad, i.e. above freezing. But when it is sub freezing, as it is now in the Northeast, the heating system cannot keep up, to the point that we've got cold fingers and are dressed for the outdoors, indoors. The boiler has "functioned" this way on the coldest of days more or less since installation, and I think it has to do with the boiler itself. Original heating contractor's service department failed at figuring the problem out long ago.

The boiler setpoint is at 180 deg F. The Economy knob is set to min, because we have trouble keeping heat in the house.

When the outside temperature isn't too cold, the boiler fires up and heats water to 180 deg F, cuts out and lets the circulator pump the hot water until supply temperature drops to 140 deg F, then fires up again. That is, it seems to operate as it should when the heat load is minimal.

When the outside temperature is cold, as it is now (18 deg F now, single digits in the last couple of days), the boiler fires up at seemingly random water temperatures, and maybe heats to the setpoint but more likely doesn't. It will frequently get stuck in something I call limp mode, running between 120 to 140 F. Often it short cycles, firing up but then shutting off immediately or close to it. Thats not enough to get this place out of the lower 50s. I have tried setting the setpoint lower, setting it higher, but it doesn't seem to help.

Tstat is an old Honeywell set high enough that the call for heat LED on the boiler is always lit, and the circulator always pumping.

If I baby-sit the boiler during limp mode, I can crank the setpoint one way or another to cause the limit circuit to be met, and get the boiler to start, though it might or might not get to the setpoint without repeating this a few times. Sometimes it will seem to work for a while, (operating above 140 deg F is what I mean by work), but if you stop watching it, it misbehaves.

Last year or so we had a heating tech from a different company than the original installer come out. He was kind of stumped and threw a temp sensor at it, though I don't think the temp sensor resistance values were out of range per the manual and pointed that out to him. Of course after he replaced it anyway as a first step; we had mild weather so it seemed to be working fine, until the next cold snap, when it didn't.

Now we've got prolonged cold weather and the boiler's having trouble keeping it 50 degrees in here. I have checked the resistance values of the temp sensor and they jive with what the manual says.

There are no flashing LEDs on the controller.

For brief troubleshooting purposes only, I also did the following for long enough to eliminate these components as the cause of the problem:
* jumpered the Spill switch. Problem continued, so re-established as-found connection to spill switch to preserve function of this important safety device. I has guessed this part might be the cause, as the chimney doesn't have a cap.
* jumpered the rollout switch. Problem continued, so re-established as-found connection to rollout switch to preserve function of this important safety device.

So, according to the trouble shooting flowchart of the manual, the next thing to replace is the controller, p/n 381-330-014WT, the Model # 1135-601 controller. So far, the only quasi-local place I have found to have it, won't sell it to me because I am a private party and not a mechanical contractor. But it's cold, and the place I think will have it and sell it to me has a constant busy signal, probably because they are wicked busy. And most searches online list it as "discontinued", though I think I may have found one place that has it.

Does anyone have some guidance for me? I'm just about ready to take a gamble on buying the controller online, but I thought I would look for a little wisdom before I do something like this. Money's tight, but we are cold.

Thanks in advance, and sorry for the long-winded post but I am trying to relay as much info as I can.
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  • WardWeathersWardWeathers Posts: 9Member
    One more piece of info in case anybody is reading this thread: the circulator pump is a Taco 007-F5, and it is mounted vertically. I noticed in a different thread here that someone noted that some circulator pumps should be mounted horizontally, so I checked the instructions for this circulator pump on Taco's site. Sure enough, Taco recommends horizontal orientation, though says vertical orientation is ok if pressure is greater than 20PSI.

    I'm pretty surprised that the original installer put the pump in that orientation since they are an old Rhode Island company that started installing oil burning boilers back in the 50s or so and are pretty experienced.

    The current operating pressure of this unit is right at 20 PSI. The GWA manual says the cold fill pressure is typically around 12 PSI, but doesn't seem to give typical operating pressure. The pressure/temp gauge has the red line set at 30 PSI, though I watched the repair tech we had in last set it there (the original installation team didn't set the red line...) . I don't really know what the proper at-temp operating pressure is for this system and/or if the pressure is too close to Taco's spec for the circulator.
  • WardWeathersWardWeathers Posts: 9Member
    edited January 2018
    Well, silence is an answer of sorts!

    With a blizzard coming today, I felt I had to act. I did manage to find a new control module, which I purchased. After making note of where everything was connected, I removed the electrical connections, pulled the three mounting screws to pull the old module, and mounted and connected the new one.

    What a difference! The thing heats like it should have from new! Shame on the installation contractor for not taking our concerns about the boiler seriously when we complained after installation, and shame on us for not pushing back more. Apparently this Williamson-Thermoflo GWA 105 had a bad controller straight from the factory.

    And, though it makes no sense to me, the boiler is now quieter in operation. It used to have a whine which is gone with the new controller.

  • BobCBobC Posts: 4,947Member
    i would write a letter to the manufacturer telling them of your problems that have existed since the boiler was new and ask them for their comment.

    It may not do much good but it will make you feel better.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • Tom_133Tom_133 Posts: 613Member
    There are no other controls on the system? Tekmar outdoor reset? anything?

    The board could be the problem, thats a tough one though to buy and try to have it not work. Did you call tech support? Hows your gas pressure when it gets really cold? Thats probably where I would start.

    I had that in Aspen Co, natural gas. Pilots wouldn't stay lit when snowmelt was on. Went to the regulator that feeds the whole complex and the thing was iced up. Nothing came up to temp in those conditions
    Montpelier Vt
  • WardWeathersWardWeathers Posts: 9Member
    edited January 2018
    BobC's idea to write a letter is interesting, though I don't know that I gain anything out of it. Surely their engineers are monitoring how many of the replacement controllers they are selling. I sincerely doubt they'll make any amends.

    Tom, there is not an Outdoor Boiler Reset, nor any other controls.

    The controller module was certainly the problem. After replacing the controller, the boiler works like a champ. It heats the water to the set point, and has a very minor subtractive differential in this extreme cold we are having. We're not going to be able to heat the house to 75 deg F in this cold, windy weather, but finally the boiler is doing what it is supposed to do. The thing behaves like a different machine entirely. I don't think I would buy another Williamson-Thermoflo given the QC issue, but at least it is working now.

    One thing is for sure: I would not use the same contractor again, only because they dismissed our concerns. A contractor is the customer's advocate, after all.
  • John Mills_5John Mills_5 Posts: 898Member
    Who made the board? That would be a 3rd party not the boiler manufacturer. These new controls are rather complicated plus they let the boiler get rather cool before bringing the burner back on again. Couple complicated with cheap since equipment manufacturers have to keep costs down for cheap homeowners and nothing holds up these days :/
  • WardWeathersWardWeathers Posts: 9Member
    That's a great question. The board is marked HSCI, which I guess is Honeywell based on a quick search.
  • EBEBRATT-EdEBEBRATT-Ed Posts: 5,631Member
    Then it's a Honeywell problem Williamson boilers are made by Weil McLain and they are fine. Your contractor is an idiot. Bell Simons has branches in Providence and have access to Williamson boilers. They usually don't sell to homeowners though. Google Williamson and call them. Maybe you can get a new board for a spare
  • WardWeathersWardWeathers Posts: 9Member
    EBEBRATT-Ed. thanks for your response. I'm casually asking around with friends trying to find a competent contractor for the future.

    There are several Bell Simons around here as you note and I did find them by looking on the Williamson-Thermoflo website, thankfully. I may give Williamson a call as you suggest to see if they will push this controller back to Honeywell.

    It might well be Honeywell's fault (after all they made the controller), but Williamson (Weil-McLain) selected it/integrated it into their system. Honeywell spins the board, Williamson packages it into the plastic front end, maybe a cursory operational test of the complete system (?) and out the door it goes for "field testing".

    This boiler is full of Honeywell parts.
  • WardWeathersWardWeathers Posts: 9Member

    Who made the board? That would be a 3rd party not the boiler manufacturer. These new controls are rather complicated plus they let the boiler get rather cool before bringing the burner back on again. Couple complicated with cheap since equipment manufacturers have to keep costs down for cheap homeowners and nothing holds up these days :/

    That doesn't sound inexpensive for the homeowner in the long run, but it does sound cheap!
  • EBEBRATT-EdEBEBRATT-Ed Posts: 5,631Member
    @WardWeathers unfortunately it seems from your post that the problem existed since the original installation so you probably out of luck
  • mfspiegmfspieg Posts: 1Member
    I also had a defective control board for Williamson's boiler model 1135-601. Make that 2 control boards. The replacement failed after 2 weeks!

    Exact same problem: when it was very cold outside, boiler repeatedly shut off at 140 degrees, even tho its thermostat is set to 180. My contractor said he knows of 2 other failures, just in our immediate area. I called W-T, and a tech there told me they get a few returned boards every month; they all fail the same way. It was first marketed around 2012 or '13, but to his knowledge no fix has been applied. The manufacturer of the board - according to him - was UTI (United Technologies inc). I'd love to wring their neck for not fixing what is obviously a common failure mode.

    Upon my 2nd, now warrantee, replacement, I again called W-T with my contractor. This time we got a tech who knew nothing of the problem, but logged our failure for their infrequent reports sent to marketing/sales/etc. So, dear Internet Readers with the same control board failures, I urge you to call Williamson-Thermoflo. Make UTI or Honeywell to fix the underlying problem!!
  • WardWeathersWardWeathers Posts: 9Member
    @mfspieg Thank you for sharing your experience with these problematic Williamson-Thermoflo boiler controllers. When I was originally searching for the control board, google searches of the part number seemed to indicate it was a UTI part. However as I noted above, when I opened the defective module up looking for a UTI mark, I found it marked HSCI instead.

    Another Wall user messaged me to tell me they had the same problem with their Williamson Thermoflo boiler. And in my search trying to figure out the problem, I found others complaining of the same symptoms on other websites. I think this problem is quite common.

    I wonder whether a call or a letter to Williamson Thermoflo would be a more effective a way to let them know my displeasure with their product. Again, they know how many of these boards are failing, since they're selling the replacements. They simply have to have an engineer monitoring this on their end. It is clear to me that they know about the problem already. They need to know that their customers are upset about it. If this is a manufacturing defect, I think they're on the hook to make their customers whole.

  • EBEBRATT-EdEBEBRATT-Ed Posts: 5,631Member
    Call them. It can't hurt you have nothing to loose. But I wouldn't expect anything. Manufacturers seldom admit their wrong
  • BobCBobC Posts: 4,947Member
    They know you have little recourse, legal wrangling takes a lot of money and if you don't win the case it's all on your dime.

    Talk to them and if they won't deal I would tell them in writing that you will be sure to never use them or their subcontractors again. It's poor satisfaction but better than nothing.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • WardWeathersWardWeathers Posts: 9Member
    edited January 22
    Received another private message today asking if the Williamson-Thermoflo GWA 105 was still working properly after I replaced the control module roughly one year ago. Answer: Yup. The boiler still works properly, even in the cold snap we have going on now. Replacing the control module solved the problem long term.

    From the sounds of the message to me, there is yet another person out there in the cold due to a faulty control module.
  • jazzmatazz21jazzmatazz21 Posts: 1Member
    Ward I am having the same issue with my Williamson currently, and today the power light actually went out. I don’t know much about these things, but wanted to try and fix on my own. Is the control module the box where all the wires plug into, and if so what model did you replace it with/ where did you buy it? Thank you in advance!
  • StarsStars Posts: 1Member
    edited March 7
    Ugh... I have the same problem with 2 of my control modules that broke this winter. Wonder where did op purchased your control module? :neutral:
  • SuperTechSuperTech Posts: 938Member
    > @Stars said:
    > Ugh... I have the same problem with 2 of my control modules that broke this winter. Wonder where did op purchased your control module? :neutral:

    Try Bell Simons.
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