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Williamson-Thermoflo GWA 105 problems

WardWeathersWardWeathers Member Posts: 9
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 Member Posts: 9
    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 Member Posts: 9
    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 Member Posts: 5,109
    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 Member Posts: 688
    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 Member Posts: 9
    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 Member Posts: 935
    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 Member Posts: 9
    That's a great question. The board is marked HSCI, which I guess is Honeywell based on a quick search.
  • EBEBRATT-EdEBEBRATT-Ed Member Posts: 7,058
    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 Member Posts: 9
    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 Member Posts: 9

    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 Member Posts: 7,058
    @WardWeathers unfortunately it seems from your post that the problem existed since the original installation so you probably out of luck
  • mfspiegmfspieg Member Posts: 1
    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 Member Posts: 9
    @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 Member Posts: 7,058
    Call them. It can't hurt you have nothing to loose. But I wouldn't expect anything. Manufacturers seldom admit their wrong
  • BobCBobC Member Posts: 5,109
    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 Member Posts: 9
    edited January 2019
    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 Member Posts: 1
    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 Member Posts: 1
    edited March 2019
    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 Member Posts: 1,336
    > @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.
  • Sklaren14Sklaren14 Member Posts: 2
    I know this was posted some time ago, but I'm curious to know what diameter was the pipes that was going to the baseboard?
  • Sklaren14Sklaren14 Member Posts: 2
    I realized that when the temperature dropped to 24 degrees my boiler cannot keep up. I have 1/2 in pex pipe that going to my baseboard.
  • anngvtanngvt Member Posts: 3
    Same boiler, two years of issues and we don't know enough about heating systems to have a clue. Our installer replaced the control board last year and it worked fine for the rest of the heating season. They tested our thermostat and said it's fine and not to replace it as it's the old mercury type and they're pretty much fail-proof.

    We had it cleaned again in October and when we had a cold night with single digits, it wouldn't kick on. The flame light blinks. Our HVAC installer said it has to be the regulator outside is freezing up. We had to wait two weeks for our propane company's one technician to be available. He replaced the regulator, added methanol, and had them drain and fill us with new propane. In that time though, we had a warm up putting temps in the 40s/50s.

    Nine days later, it hit 10F last night and no heat from 5 p.m. to 1 a.m. this morning. We called our HVAC guy who said it has to still be moisture in the tank and regulator as only the flame light is indicating an error. He told us we had to call our propane company so we did that while he was here. He talked to that technician and left.

    At 1 am., the technician finally came out. It happened to start working again while he was here, so he knows we're not imagining things. The propane technician said you can't get moisture in the tank as it's pressurized and the regulator is fine. There was no frost build-up on it, he heard propane flowing through the regulator, and he said it can't freeze and then unfreeze by itself when it's 5 degrees outside. He said our HVAC guy is full of ... telling us that it's moisture in the propane tank and regulator. He said there is clearly something wrong on the boiler, but he couldn't see anything wrong.

    Meanwhile, we have an 1,100 sq. ft. older home that is usually right at 68/70 when the temperature is over 10 outside, but the minute we hit 10 degrees, that flame light blinks and we have no heat. I'm sick of emergency technician bills and not having people really be able to diagnose the issue and find a solution. If anyone has any idea on what we need to push for next, we could use the advice.
  • Jamie HallJamie Hall Member Posts: 12,863
    How big is the propane tank? Is it vertical or lying on its side? And what is the demand of your boiler? When cold temperature problems hit with LP, sometimes it is simply that the tank isn't big enough to evaporate the LP fast enough, and the gas pressure drops and the boiler won't light off.

    Have your gas company verify that the tank is properly matched to the demand.
    Br. Jamie, osb

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • anngvtanngvt Member Posts: 3
    Thanks. We have two 120-lb vertical tanks with only the boiler and clothes dryer using propane. We have a heat pump water heater (electric) and stove/oven is also electric. Typically, when it's at its coldest in Vermont, the gauges drop a total of 3% per day. The house is pretty tight with new windows and doors a year before the new boiler, so at most we use 500 gallons per winter. That's why our HVAC guy insisted they should drain the tanks, add methanol, replace the regulator, and put in all new propane. He thought since we'd gone from April to November without needing a fill-up, it could be the propane was a summer fuel, but Amerigas insists they only use winterized propane in our area and that our HVAC guy doesn't know what he's talking about.

    I am going to ask about the tank size and see if they say anything. I'll let you know what they say.
  • Jamie HallJamie Hall Member Posts: 12,863
    105,000 BTUh input. I'm going to bet that those two vertical tanks are too small, even if the regulators and piping are perfectly matched so they really operate in parallel. By the charts available to me you should have a 500 gallon tank.
    Br. Jamie, osb

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • anngvtanngvt Member Posts: 3
    They claim that it's not our set up, that a boiler and gas dryer that's used twice a week is not overwhelming the tanks at all per their charts, especially not when this house has been on two tanks since we moved here 27 years ago and the only changes have been ditching the gas water heater for a heat pump and upgrading from the old boiler to the new high-efficiency one. The neighbor's house has the a similar boiler apparently and a gas oven/stove, gas dryer, and gas fireplace and she's not having issues, so they are convinced it's our boiler causing the problem. It was warmer last night so we had no issues. All we can keep doing is reporting it when it does dip into the teens and single digits.
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