Click here to Find a Contractor in your area.
Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Weil-McLAIN boiler ECO boiler control broken

I bought that boiler several years ago. A few days ago the controller (I believe it is the problem) decided it would only support the DHW. No changes; just broke. And the control panel also hung up on just the DHW - then turned into an unusable screen junk that had become useless. I have no idea what is going on. This will be the fourth time we have lost heat in the winter because of the multiple boilers. And it is already a week.
Having some issues over a bunch of years, I had bought a controller and display "just in case". Unfortunately, I bought the wrong controls. I initially thought I had bought an EVG boiler - wrong. So now it is broken and my carefully stashed away controller is actually for the EVG I thought I had, not the ECO. I did not setup this controller. And just for the sheer joy of it, the installation for the whole control system may be used for automatic configuration ONLY ONCE and then you have to go back and do it manually. And manual is a serious mess to do. That is not my field of expertise.
I have spent a lot of time on trying to figure out a way to use the EVG set. It was rather expensive. I am hoping there is a way to deal with this. Looking at all the pieces, there seems to be some possible approaches. I was in the process of figuring out how to do that. And I ran into a couple of barriers. The most inconvenient location is the changes to P2 and P4. For these two, the number of circulators has gone from 1 in P4 for the "boiler circulator" and P2 adds a third circulator so there are the same circulators to use. I believe I only will need 2 like they were using before. They also changed the socket connector in P4. I don't have anything to substitute for the connector identified as that Boiler circulator. If I do not use the circulator in P4 I could open up the case and wire around the new wire distribution.
Some wires change pins locations but use something in the same little set of pins.
If I can find a socket matching the long P4, I might be able to be cut a hole under the wire around the new ones and mount above. Soldering and sucking (don't be nasty) I am good at.
I look forward to an instant solution from the forum
Having some issues over a bunch of years, I had bought a controller and display "just in case". Unfortunately, I bought the wrong controls. I initially thought I had bought an EVG boiler - wrong. So now it is broken and my carefully stashed away controller is actually for the EVG I thought I had, not the ECO. I did not setup this controller. And just for the sheer joy of it, the installation for the whole control system may be used for automatic configuration ONLY ONCE and then you have to go back and do it manually. And manual is a serious mess to do. That is not my field of expertise.
I have spent a lot of time on trying to figure out a way to use the EVG set. It was rather expensive. I am hoping there is a way to deal with this. Looking at all the pieces, there seems to be some possible approaches. I was in the process of figuring out how to do that. And I ran into a couple of barriers. The most inconvenient location is the changes to P2 and P4. For these two, the number of circulators has gone from 1 in P4 for the "boiler circulator" and P2 adds a third circulator so there are the same circulators to use. I believe I only will need 2 like they were using before. They also changed the socket connector in P4. I don't have anything to substitute for the connector identified as that Boiler circulator. If I do not use the circulator in P4 I could open up the case and wire around the new wire distribution.
Some wires change pins locations but use something in the same little set of pins.
If I can find a socket matching the long P4, I might be able to be cut a hole under the wire around the new ones and mount above. Soldering and sucking (don't be nasty) I am good at.
I look forward to an instant solution from the forum

0
Leave a Comment
Categories
- 80.9K THE MAIN WALL
- 2.5K A-C, Heat Pumps & Refrigeration
- 36 Biomass
- 394 Carbon Monoxide Awareness
- 2.6K Controls
- 1.4K Domestic Hot Water
- 3.7K Gas Heating
- 100 Geothermal
- 130 Indoor-Air Quality
- 2.3K Oil Heating
- 30 Pipe Deterioration
- 562 Plumbing
- 4.2K Radiant Heating
- 333 Solar
- 12.1K Strictly Steam
- 36 Water Quality
- 7 Industry Classes
- 50 Job Opportunities
- 7 Recall Announcements
Comments
If it's a gen 1, then it would be
model1176-120
W-M replacement 381-330-018.
Did you try shorting terminals 1 and 2 on P15 to see if a call for heat happens? You may have a DHW stuck, so try disconnecting 4 and 5 on P11.
I've had these freeze up on the display, and unplugging and replugging the 4 wire connector to the display will sometimes unfreeze them.
The wrong one is Evergreen 550-225-406_0817
I will put the original controller back in and try what you suggest. And if you have any further suggestions.
The way it was behaving when it initially stopped working properly. The main control from the controller on the wall for all the control points and it said "no heat". While that was cycling off and on, the boiler kept short cycling for only the DHW. Never went to the other heat requirements.
I will probably buy a replacement soon since I have not been real successful. It is more than a week and it is cold out here. It is not very comfortable.
If someone out there has a like new controller and display for the ECO and like to get rid of I would be interested.
rarely did I have the correct part on the truck for those crazy controls they use.
Retired HVAC Contractor from So. Jersey Shore.
Cleaned & services first oil heating system at age 16
Specialized in Oil Heat and Hydronics where the competition did Gas Warm Air
If you make an expensive repair and the same problem happens, What will you check next?
I put back the original controller. Still garbage. The display device is largely unreadable. So I still do not have a solution. I have no idea how to deal with this situation. It looks rather like really old Sanskrit. I think I could make the newer version if I cut up the socket they used in one location. I could try snipping out that one connector and solder everything.
Is there anyone out there that knows enough about the controller and knows if the removing the odd socket would be the last thing I needed to do. It is P4 and got reconfigured. They went to a new connector design.
I am afraid I am going to have to buy both a new controller and the display. It is quite expensive. I thought I did a good thing moving from an earlier boiler that had problems. I really don't want to buy yet another boiler. But we are getting quite cold in the house. And my wife is rather fragile.
Ideas appreciated.
I have to admit that if I could get access to the burner controls directly I'd go old school -- but on that boiler (or, for that matter, any of the new advanced boilers) you can't.
In my humble opinion, you -- or your contractor -- will need to source the correct display and control module for that specific model boiler, and install them.
And, while you are at it, provide a good computer grade surge protector on the 120 VAC input power line.
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
spare controller which is probably not going to be used.
The failure was sudden. It started running the DHW for short times, then doing it again. Essentially short period (maybe a few minutes) forever. No heat for the rest of the installation.
At the beginning of strange behaviour, the house heating control system indicated NO HEAT.
I do have a high grade surge protector. It is saying with the little green lights that is OK. We did nave a power outage about a week before this happened.
I thought I could get somewhere with the spare controller - but one changed socket stopped be. I am not sure where I could get something to jerryrig. It should work if I could just do new wiring by cutting up something with the spare. The connections required are soldered to the mother board. Simplest would be to make up plug and put it in where it needs to be. But I do not recognize the socket.
I have been sitting here trying to figure what service vendor to choose. Selecting one can be tricky. I am in the area of Burlington WA. There are a bunch; but getting one that understands the boiler could get a bit iffy.
If I had the two plugs to put in the sockets on the board, there is a high probability it will work. I do not see any other booby trap that I can not deal with.
I have screwed around for a week now. It is pretty cold in here. Wife is sick.
The plug on the board is 1 1/4" long, and 1/4" wide. There are 5 male pins in the holes of the board socket. The holes on each end of the socket have a flat side on one side. The flat sides would be to key the two plugs. The one end has two pins used, and the other end has 3 pins used. So I would need individual sockets to fit over the 2 sets of pins.
Individual wired sockets fitting over the pins on the board could work. All of the pins are power suppliers.
If anyone knows of a matching plug (or creative ideas) - please let me know. It is not being fun.
Eco Series 2 Manual pages 124-125...
Control module and housing 381-330-029
Display board and housing 381-330-030
https://www.weil-mclain.com/sites/default/files/field-file/Weil-McLain_ECOSeries2-BoilerManual_0119-web.pdf
Is your boiler an Eco Tec combi boiler with tankless DHW?
I've scanned Ebay for you, but no dice right now. If I had a spare I'd send it to you to try.
I do know the boiler will run without the display connected. So if the display were fired the boiler would still function. But I'd bet it's the controller.
What does your plug look like?
Retired HVAC Contractor from So. Jersey Shore.
Cleaned & services first oil heating system at age 16
Specialized in Oil Heat and Hydronics where the competition did Gas Warm Air
If you make an expensive repair and the same problem happens, What will you check next?
The set of pins are in the upper right corner of the EVG controller. The plug on the EVG board is 1 1/4" long, and 1/4" wide. There are 5 male pins in the holes of the board socket. The holes on each end of the socket have a flat side on one side. The flat sides would be to key the two plugs. The one end has two pins used, and the other end has 3 pins used. So I would need individual sockets to fit over the 2 sets of pins.
Part numbers: They are what is printed on the manual pages. One part number is the normal controller for an ECO boiler. Which is my installed boiler. The other controller I tried to use is the controller for an EVG. I am reasonably convinced that the EVG controller would work if I chopped up that one set of pins.
flat_twin - I do not understand what your point is.
Look further in the manual for the complete parts list.
Control module and housing 381-330-029
Display board and housing 381-330-030
They might be. They might not, and if they weren't, it would be quite impossible to figure out what malfunctions and errors -- or out of spec. operations -- were occurring.
Not quite as spectacular as the havoc caused by throwing an engine control module from a gasoline Ford F150 into a diesel Ford F350 (they are, by the way, pin compatible -- but hardly plug and play) -- but close.
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
I have traced all the pins inside the controller and where they go for the entire controller. I believe I could make it work. That socket in the upper right corner is the blocking problem. But I need heat now and I am not being particularly successful. I am going to try to find a local contractor that understands.
Thanks for everyone's thoughts.
I put everything back to the initial configuration. I was unable to make it work. I was unable to get my brain to help. I did not really understand the WM instructions. It did not work.
Finally I was able to get the original installer. He was working on a mountain in remote location in a no-service phone area. He understands the manual. He returned and I got a call from him literally just as I was about to start contacting random heating providers. He came today and worked on the system. Most likely source of the problem was a wide area power loss shortly before the boiler failed. Turned out that one of two sensors on the SS boiler had failed. Not an impressive life time for such an expensive device. I may put in a second surge protector.
Contractor is trying to find a replacement sensor. No idea when it will be here. Wife really annoyed. But it is clearly not my fault (this is an important point). Two weeks of cold house has been rather annoying for both of us. Three blankets and dashes to the bathroom.
Thanks for your support.
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
Depending on which sensor failed, you can swap the return sensor for it and may get heat again. I dont understand what all this screen messed up would have to do with a bad temp sensor though.
The W-M boilers are made with as many off the shelf parts as possible with the focus of having fewer parts which are unique. At least that's what my W-M rep said. I've have good luck with the W-M ECO and EVG line. Simple units compared to other mod/cons.
Purchased a new ECO controller. No discernible change except to my bank account.
Original installer and I have just not found a problem. I have gone through all of the wiring. Talked to the circulators manufacturer to confirm the green/blue/brown wire markings. They verify the internals can use either wire in the circulator.
Ongoing lack of expertise on my part. Going through the WM ECO manual has not been understandable. We had a terrible time trying to do what is required to get the boiler controller to work. Still no working. We just could not get the little display unit on the outside of the boiler. I have searched for bad wires repeatedly. Swapped boiler sensors around and overnighted new ones. No change.
Last night, I actually got the DHW and Heat to run. I do not know what I actually did, but for the first time the boiler recognized both heat paths. I heated some water, and it then started on the heat. I left it running last night to start heating the system piping. This morning the boiler is still heating, but only for a few seconds, and then just continues circulating. Over and over.
I used a IR thermometer and the ever useful hand to look at piping. The boiler goes up to heat temp, various places on the near piping go up to as much as 60 degrees in the general area, but does feel like any significant flow. This is a large house, but the downstairs is unheated. Floors are concrete.
I stopped now to the boiler and I noticed new possible problem. It may be at the root of things. This may be where stupid is in full control. One of the AquaMotion circulators has all of its lights on. Neither of us paid attention to the pump. Up rather high on the wall and normally has some display lights on most of the operational time. I have the awful feeling that this is the whole problem. Bad pump. It is running and you can hear it (very quiet).
The pump was not moving water. Boiler tried to heat. Worked fine for DHW pump, but the pump for heat kept trying without any flow.
Everything working now. But I have a new $500 controller I that I don't need and a very very annoyed wife.
Everything seems to be working. Now I am working on getting the Tekmar interfaces to work with CrossManifold controls. I think CrossManifold may have been acquired. I saw a picture that looked really nice on a different site. Better than the original I have. They are a clever design.
I am working at making sure removing the wires that usually go to the remote valves without destroying the use of common connections. I makes me nervous. I have a real problem understanding the interface specified between Tekmar and CrossManifold. I have some relays CM provided, but together they make a bunch of wires and power.