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Weil McLain Ultra

mike faust
mike faust Member Posts: 58
One of our installers had originally started this thread with that question using our office computer...


  • mike faust
    mike faust Member Posts: 58
    Weil Mclain Ultra Reset curve

    Is their any way to change reset design temperature to lower than 32 degrees F. If not, does anyone have any input as to why????
  • Tim_53
    Tim_53 Member Posts: 5
    Dip switch ?

    Under the cover were the AFM is.

    "The front of the AFM includes a single DIP switch that either Locks or
    Unlocks the Access Level item in the Miscellaneous (MISC) menu. Once
    Locked, the access level item is not longer shown on the Remote Display
    Module and the access level remains at the last setting. To indicate if the
    AFM is currently locked or unlocked, a symbol representing a padlock is
    shown in the lower right hand corner of the display."

    This is from the manual.

    check this out, I have no problem changing mine
  • mike faust
    mike faust Member Posts: 58

    Is this in the "control supplement" manual... Thanks for the info!
  • Floyd
    Floyd Member Posts: 429
    R U talking gas or oil??

    If it is gas, the info is also on WM's website and is done through the keys on the display on the front.
    While in there, you may want to tweak some of the other things, like the boost feature.

  • mike faust
    mike faust Member Posts: 58
    Gas Ultra

    This is on the gas system. What type of tweaking on the boost mode?
  • Floyd
    Floyd Member Posts: 429
    Depending on the type of

    system you have you are better off to set the boost to 0 which shuts it down and keeps the boiler in true reset mode.


  • You're sure it's not in the addendum to the supplement to the errata of the installer manual?

    Just kidding, but seriously the documentation on ultra control settings is ridiculous. The number of manuals you have to have just to set basic parameters is silly.
  • scott w.
    scott w. Member Posts: 207

    Just curious, was wondering if some one could explain when or why the design tempature would need to be changed.

    Also interested in understanding boost and what advantages of having reset at 0?

    I have an ultra and would like to know a bit more about some of the why's & where's of some of the settings. Want to be a bit more educated when discussing the boileer with the heat guy.

    I have learned a good bit about boilers from this site. Some great people on this site who are willing to share knowledge.
  • Jodie
    Jodie Member Posts: 5
    Change Ultra parameters

    There is no need to have a mod/con boiler to go to high fire(190) in 32 degree weather. The parameters can be changed to -4 @ 190+/- or depending on what you design temps are fo your area. If this parameter isn't changed, then the application is kind of defeating the purpose of having a mod/con boiler with full outdoor reset, and fuel is being wasted.
  • mike faust
    mike faust Member Posts: 58
    Can I get an Amen!

    Agreed.. Why have an outdoor reset control with only one design temp setting. As I have found out, you need to call weil Mclain to have them walk you through a proceedure which is not outlined in any manual.
  • mike faust
    mike faust Member Posts: 58

    If you have enabled the outdoor reset system on your weil mclain ultra by installing the outdoor sensor, the design temperature should be adjusted to achieve maximum performance. When your heating system (piping, radiation, etc.) was designed, the engineer should have done a load calculation on your structure. This calculation was based on many factors one of which being the"design temperature" AKA the coldest outdoor temperature your local climate can dish out. And on this coldest day the engineer should have calculated a temperature the system water would need to be in your system tokeep your house 70 degrees. With these two #'s he sized he radaition. Outdoor reset automatically adjusts system water temperature to give you a correctly sized system for every outdoor temperature from 65 degrees down to design temperature. In my area design temperature is 0 degrees. Pretty cool stuff!
  • Tino
    Tino Member Posts: 5
    Weil Mclain/Utica

    Any recommedations on brand for a high efficiency boiler?
    I am looking to convert from oil, and also build an addition of ~2100sq feet on top of the 1100sq ft now. In total ~3200sq ft house. I have done a little research and would like to consider Weil Mclain or even Utica. Also I gather that if the boiler modulates that is a good thing. Can anyone help me out. Thanks
  • Tino
    Tino Member Posts: 5
    weil mclain/utica

    Any recommedations on brand for a high efficiency boiler? I am looking to convert from oil, and also build an addition of ~2100sq feet on top of the 1100sq ft now. In total ~3200sq ft house. I have done a little research and would like to consider Weil Mclain or even Utica. Also I gather that if the boiler modulates that is a good thing. Can anyone help me out. Thanks
  • scott w.
    scott w. Member Posts: 207
    design temp

    Thanks for the info on design temp. If not dealing with this day to day, sometimes just need a review cause I forget.

    Last year after reading the W/M manuels and looking at this site. I decided to try to see if I could save a few bucks by lowering the high limit temp from 180 to 150. That only worked up til Dec.

    Unfortunatly, when my house was built(1929) the dead men decided to run some of the supply and return lines in a chase in an outside wall. Walls are brick exterior with clay tile and plaster on the inside.

    When outdoor temps dipped below 15 degrees the CI rads would not heat up enough to be comfortable. Cold third floor.

    My ccf consumption last Nov.-Dec. per 24hr day was between 5 and 6ccf on a 40 degree day with nights dipping into the high twenties.

    I am using way more CCFs per day this year Nov. & Dec and can't figure out why? I don't know if lowering the high limit temp saved that much fuel last year. Didn't lower the high limit temp on the boiler this year.

    Even on warm days like 45 to 50 with night lows in the low thirties I am at 10 ccf per 24 hour period. The only other variable was adding two CI rads. Both out all of last years heating season due to renovation.

    Would adding the two CI rads make that much difference?

    Any suggestions or possibilities of fine tuning the ultra to save gas consumption?
  • Jodie
    Jodie Member Posts: 5

    If you look on the Weil-Mclain website, click on the professionals section, then click on the "Service information" section, and click on the "Product Manuals" section. Then click on the "Ultra Series 2"
    section & read both the " Control Supplement" & " Control Addendum Interface Kit" manuals. There is your answer. If this is confusing then call your technician.
  • Floyd
    Floyd Member Posts: 429
    150 will make a diff.

    Scott, I'm sure that the two rads have a bit to do with the extra usage, however the 180 temps. will kill eff. also. @ 150 the boiler will run much more eff. than @180. Now I'm talking a few % but that adds up... Run your temp. back down till the rads don't make enough heat and then slowly raise the temp to where it will keep up. Once you find that info out then by hooking up the outdoor sensor and setting up the reset curve on the boiler you can have the boiler do all of that for you. Also, you can limit the high fire of that boiler... chances are that you are oversized and that you could cut back the high fire to throttle that boiler back and still heat just fine saving even more money. ( the boiler also heats more eff. the lower the fire of the boiler)Also, this helps to keep the boiler from short cycling, they have a tendency to ramp up to high fire and then when the warmer return water starts to come back they don't ramp back fast enough and start to slam off/on. That can be helped also by changing the differentials of the on/off temps.
    There is so many things you can do with the Ultra boiler if you want to take the time to dig into it real deep.

  • scott w.
    scott w. Member Posts: 207
    outdoor reset

    Floyd, I do have outdoor reset hooked up. A proper heat loss was done as the heat guy laid out the floor plan of all three floors, got the loss for the new replacement windows, walls, insulation, ect. The ultra I have is a 230 for a 4,400 square foot house.

    I think the ultra wasn't "fine tuned" when installed. I think 300 CCf, my guess, for Nov 15 to Dec 15 is high as warm as it has been here in southwestern Pa.

    Would like to "dig into" how to fine tune for fuel savings?
    Any suggestions as to where or how to do this?
  • Floyd
    Floyd Member Posts: 429

    You are WAY oversized there Bud.....
    My house is bigger than that, N of Wolliamsport, Pa. with no insulation and I heat it with a 155 cut back from 5000 RPM to 3500... I would check out the third floor problem, it may be more of a water circulation problem than a temp. problem.
    As far as digging into the workings of that boiler, I am not that great at transfering what I know to others.. my mind just doesn't seem to work well at doing that...I know what I know and am thinking but just have a hard time transfering that knowledge... however, checkin to boilerbuff.com... there are a coupling of guys there that are great at communication and have played obsesively with that MCBA control... they should be able to help you dig into it an tweak that puppy out...
    Feel free to eml me also if you have specific questions, I do what I can to help...

  • scott w.
    scott w. Member Posts: 207


    The third floor is fine when the water temp is 180 when its cold. I just can't use the high temp limit at 150 when the outdoor temp is in the teens or lower As I said some of the supply & & returns to the third floor go up outside walls in a brick wall. I think the pipes get chilled a bit going up those unisulated chases. No way to insulate unless I break up the plaster.

    My heat guy did do an extensive and I do mean extensive heat loss calc. I had to answer quite a few questions about how much insultion what my plan was on the renovation. Changing windows ect, what rooms were above an unheated space, measuring all the windows, size of rooms what i planned to insulate. SO i am pretty sure we are on the mark.

    We removed 300,000 BTU W/M cast iron boiler with a 75 gallon per minute pump. Now talk about way oversized. They previuos owner's gas bill was through the roof.
  • Floyd
    Floyd Member Posts: 429

    First off, if your flow was right going up the chase there is no way you would lose that much heat...next, I can assure you that every heat loss program out there has at least a 30% cushion built into it. The ONLY way you can accurately measure your heat loss is the find the balance point where your boiler can no longer keep up when it is running 24/7. That can be done but it takes alot of time, thinking, and fiddling....
    Hopefully your boiler is piped correctly, there are alot of Ultra's that don't work to their full potential cause of incorrect piping, they will still work, but not like they could....would have to see pics of yours to see if it's right.
    You say southeast Pa.?? could I ask where??? I have family down there...

  • mike faust
    mike faust Member Posts: 58

    This may sound like a dumb question.... but you just need to be sure. Was the design temperature setting changed or is it still in the 32 degree setting? This DRASTICALLY changes the temperature curve with outdoor reset in operation. The high limit can be changed simply by entering into the parameters section, but the design temperature setting needs to be changed with a bit more of an extensive procedure. One will affect performance a much as the next.
  • Everyone thinks,

    > Is their any way to change reset design

    > temperature to lower than 32 degrees F. If not,

    > does anyone have any input as to why????

    "tweaking and screwing" with settings will make "astronomical savings",,,,NOT SO,,"basic settings" entail about 95%, trying to achieve higher only voids your warranty,,,many of us are "versed" in tweaking, but the H.O.(savings at a minimum), will wind-up losing!,
    Try to remember that!

  • mike faust
    mike faust Member Posts: 58

    I am only suggesting setting up the control system for its designed intened purpose. I would not consider "tweaking" a system in any other manner. Any system adjustments should be carried out by a qualified heating professional, not the home owner.
  • Mike F

    Well then what are you asking?
    Can you do these things on an Ultra?, absolutely, would you remember how?, could be.
    Just remember, Floyd is stating possible things that can be done,, after you get-it in there.
    If your just "kicking tires", maybe this was premature.

  • Rick_70
    Rick_70 Member Posts: 1
    Mike F

    Guy's. I am a rep for Weil-McLain. I have the NH and Central Mass area. The best way to set up the Ultra boiler for the first time is to have the rep come out and help. Up here in NH I have as many tech's as the Co. can spare and give a mini seminar in the basement in front of the boiler. Never a bad idea to talk to the rep when a question arrises if you have the time. We are very busy this time of year but leave a message and we will get back to you or leave me a message and I'll email you back. We need contractors to understand the boilers potential so please do not hesitate to call us.
  • JRowl
    JRowl Member Posts: 1
    Church Warden

    What are the recommended temps for supply & return settings, boiled is a little slow to heat up halls. Current supply 180F, return 120 f Can the outside temp setting be changed from 0F to sat 25 F to increase modulation rate & heating rate?
  • Zman
    Zman Member Posts: 7,542
    New Thread

    This one is is over 6 years old.

    If you have a question please start a new thread.

    We would need a lot more details.....

    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • Jean-David Beyer
    Jean-David Beyer Member Posts: 2,666
    Why post this in a 7 year-old thread?

    "What are the recommended temps for supply & return settings, boiled

    is a little slow to heat up halls. Current supply 180F, return 120 f Can

    the outside temp setting be changed from 0F to sat 25 F to increase

    modulation rate & heating rate?"

    You cannot really answer a question like that without a lot more information.

    We would need the exact heat loss of each and every room and heated hall. We would need the radiation and convection of each and every emitter. We would need to know the ranges of outside temperatures, the desired indoor temperatures, and so on.

    I am not a heating professional, but I do have a W-M Ultra 3 mod-con boiler.

    To set one of these up, and I imagine this is true of all mod-con boilers with outdoor reset, you need to set the reset curve(s) so that the boiler provides just enough heat to heat the space. And, preferably, the maximum temperature supplied to the load should not exceed 130F so you get condensing. If you are running normal sized finned tube baseboard, you will probably have to go somewhat higher in cold weather, but losing efficiency in cold weather is probably more acceptable than being too cold. Mod-con boilers are at their best with radiant heat, where low supply and return temperatures are the rule. Mine runs at 76F when it is 50F or warmer outside. When it is 8F outside, it runs at 120F, and if it goes down to 0F outside, it is now set to supply 128F water. Design temperature here is 14F so it should almost never go down as low as 0F. But it has been below 3F twice so far this year. In previous years I have not seen it go below about 9F.
  • SWEI
    SWEI Member Posts: 7,356

    Start a new thread, and give us a few more details on the system in question.