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Time to Upgrade my Modcon

TinkeraTinkera Member Posts: 15
Hello All,

First of all, MANY thanks to everyone here for the incredible education and Learning experience this site has given me for Many years..... 10 years ago i installed a WM Ultra series 1 when they first came out.... boy have i abused it do to lack of maintaining and cleaning it.... it still runs without a hiccup... I am impressed and cant wait till the spring to rip into it and see its condition..... Now being retired from Building Maintence its time for me to Finally upgrade MY entire system.... Panel rads and trv's going in throughout the house..... low temps and condensing from now on...... Looking to go with a nice stainless steel fire tube boiler.... Lochinvar, triangle tube, WM 97+, and Slant Fin CHS all seem to have pretty much the same HX..... So, Which Manufacturer's Controller does Everyone here seem to Like the Best as far as its abilities?????  So Much has changed since I set up the WM PHD controller....... Im gonna truly enjoy getting my hands and tools dirty again, its been a while....



  • TinkeraTinkera Member Posts: 15

    Also will be putting in a Buffer tank for the shoulder seasons and when my smaller zones call for heat.... This should minimize any short cycling issues..... Also my new heatloss calcs have changed since i did the first boiler.... have done many improvements to house since then...... Will be all alpex runs from manifold to panel rads......
  • ZmanZman Member Posts: 3,517
    Sounds fun

    Good call on the firetube. How many different temps do you think you will run? On a new system or a complete remodel, you should be able to size your emitters for a single temp. All the firetube  boiler will manage one temp well. As you get more complicated the controls may make a difference.

    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • M LaneM Lane Member Posts: 123
    My $.02

    I have installed several Knights and Triangle Tube Prestiges. Very happy with both.
  • TinkeraTinkera Member Posts: 15

    Will Just have one space heating temp..... Plan on designing around a 130 or 140 temp.... Since im tearing out all old baseboard and convectors, I will size all the new panel rads for 130 or so temps on design day.... boiler will also have an indirect set up on proprity so that will probably get 170 or 180 temp to recover asap......upstairs will be on a smaller zone and controlled by thermostatic heads on the manifold..... everything will pe piped off the buffer tank so that should help with any short cycling...... total heatloss for the entire house, basement and 2 floors comes in at 58,000.... this may be a little on the high side but dont mind overestimating a touch as opposed to under..... Also no sure which SIZE boiler to go with?????  AN 85 or a 110????  Both should do just fine with the modulation rates and the buffer tank, but the 110 may recover the indirect quicker.... Is it better or more efficient to have the 110 running at say 40 to 50 % to cover the heating load or to have the smaller 85 boiler running at say 50 or 60%.... is either situation better or more efficient????   With the 4 boilers listed, Which control package do YOU guys who install these prefer????  Since i now have the time to adjust and tune the boiler settings, Which Manufacturer do you guys prefer as far as the Control package????

    Thanks for your input.....  Haved learned so much from everyone here over the years.....
  • ChrisChris Member Posts: 3,056
    It's Not

    The high end of the modulation rate that causes short cycling its the low end. Boiler will never go to 100% unless you need it but you are limited on the low end. Don't know what your DHW demand is but why not use a Vitodens B2HA-19 or a small Loch WHN the low ends are like 11K btu/hr, add storage on DHW with a 140 tank temp and mix down.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • hot rodhot rod Member Posts: 7,094
    Hard to find a bad brand

    I think all the major boiler manufacturers have stepped up the quality and features of their mod-cons. Tough to find one brand head and shoulders above the rest. Looks like the components under the hood has the same brand on most, anyways.

    Probably many installers buy from the folks they know will support them, or local supplier brand preferences maybe.

    The movement does seem to be towards fire tube or large diameter spiral tube design.

    I like your design plan and would give a thumbs up to a bit of a buffer tank. I added 50 gallons to my 120K Cadet. It fires about once an hour in cold conditions. The boiler/tank is on the control reset inside the boiler.

    Mixed feelings about the onboard DHW plate HX. Works great in the mild months, struggles with 40F water temperatures. And the long galv plumbing runs in our old, crawlspace home presents some un-comfortable cold sandwich effects.

    The solar pre-heat handles at least 3 months of DHW without firing the boiler at all. consider a buffer tank with a lower coil to add solar down the road.

    We have over 400 people signed up for a mod con boiler piping webinar tomorrow, must be a hot topic :)
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • TinkeraTinkera Member Posts: 15
    buffer tank

    Planned on using either the caleffi 25 gallon or the boiler buddy 30 gallon tank.... Was looking into the Whn series boilers and figured on putting the system sensor in the buffer tank to control the system...... and use the boilers ODR to control the temps...... Also noticed the Lochinvar can use a 0-10vdc  Variable Voltage as the primary pump..... Wonder how this would work out as far as the Delta T on the boiler loop???? So much NEW Technology since i put in my "OLD" Ultra boiler.... My indirect is 40 gallon Squire..... We have usual hot water needs, have 2 bathrooms and washing machine and dishwasher.... No Marathon Tub fills or anything like that...... I wouldn't want to go too small on the boiler as far as sizing much under the 85..... Would feel more comfortable with the Buffer tank and a LITTLE extra boiler without oversizing too much??????  But Alas thats why I'm asking for REAL WORLD opionions from you guys.....

    Chris,  Do you think i might get myself into trouble if is size the boiler too tight to my heat loss without any cushion???

    Thank you all
  • kcoppkcopp Member Posts: 2,774
    I guess I am....

    confused why if the boiler is only 10 yrs old and still works why replace it?

    Sounds like it needs some tlc and you are good to go.
  • TinkeraTinkera Member Posts: 15
    Better and Newer technology

    Yes my Wife asks me the same question....LOL... The Ultra I put in as a Replacement for my OLD 40+ cast iron Oiler that was slowly giving up the ghost.... The ultra was Oversized from the get go cause i had plans of adding on to the house with a Big Dormer and a larger dining room.... As things sometime happen, plans fell through.... Also was too busy Working and never got around to replacing and upsizing the radiators and emitters to take advantage of the Condensing technology..... So now that i Have time to do it correctly, I plan on doing it RIGHT this time.... Want to REALLY see the Savings these Boilers and heating systems were designed for.......
  • hot rodhot rod Member Posts: 7,094
    roll the dice

    the worse that could happen with tight sizing is at below design conditions the room temperature slips a few degrees. There are charts available to show how often your area is at and below design condition, it's not a very common condition.

    But if you believe weather conditions are changing and temperature extremes are more and more possible, error accordingly.

    I doubt anyone here has that answer but many "easterners" learned about design and lower temperatures this winter. It's more guess than science these days
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • TinkeraTinkera Member Posts: 15

    Yes this is a Hell of a year on heating systems and Design temps..... LOTS of windchill and infiltration this year for sure.... I think i would sleep better with a little more boiler than a little less..... With my Heatloss at Design temp I think the Lochinvar 085 will fit the bill ok with the addition of a buffer tank....  Do you guys think I would see a difference in DHW recovery if I stepped up to the 110???  In other words do you feel the the 085 will satisfy the recovery of my 40 gallon indirect without affecting the hot water delivery to me????  We have just your average hot water usage.....  My current boiler is oversized so the hot water tank recovers pretty rapidly, i wouldnt ever have lack of hot water.....

    Thanks again
  • SWEISWEI Member Posts: 7,356

    What is your calculated design day heat loss for the building?  What was the design temp used, and how does it compare to what you've just experienced?

    The number I'm currently concerned with is the ratio of the boiler's minimum firing rate to the design day heat loss.
  • TinkeraTinkera Member Posts: 15
    edited January 2014
    Design temp

    I Did the heatloss figuring on a Design day temp of 0... and came up with around 58000 btu.... this may be a bit on the high side..... Im in the northeast and after this year i think 0 may be a fair number indeed......  Im going to repipe the whole house with Alpex and panel rads.... figure on using a design water temp of 130 and sizing the panel rads accordingly..... right now system is so mismatched with oversize boiler and undersize radiation and no condensing at all.... This is why now that im retired and have time, i will do it RIGHT this time around.... i have learned so much in the last 10 years and Truly admire those of you who can experience this passion everyday as your career...... I did lots of boiler maintance and repairs in my career but on older bang bang and commercial stuff.....  This is a wonderful learning experience for me... even an old dog like me can learn new tricks.... 

    Thanks for your help
  • knotgrumpyknotgrumpy Member Posts: 207
    Good job, Bob!

    Enjoyed the webinar this afternoon!

    What was the website for the Gianoni animation?

  • hot rodhot rod Member Posts: 7,094
    thanks Mark, cool factory tour at link
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • SWEISWEI Member Posts: 7,356

    Minimum firing rate on the WHN085 is 17k.  The WHN055 is 11k.  I'd lean towards the latter if that heat loss calc is even possibly high (they pretty much all are, in my experience.)  A truly right-sized mod/con installed right is a thing to behold.  They stay on for hours or even days at a time.  You can literally hear the efficiency...
  • knotgrumpyknotgrumpy Member Posts: 207
    Very cool!

    So any boiler that has a Giannoni Heat exchanger in it has purchased it from Sermeta?  Like your little Cadet?
  • TinkeraTinkera Member Posts: 15

    Ok, so i was thinking of going with the 85 also...... Will this recover the indirect tank in a reasonable amount of time..... As i said, right now im spoiled by a much oversized boiler that takes care of the indirect in No time flat.... LOL...... never even came close to running out of hot water, but again our hot water useage is Average.......  Just to go one step further with my Heat Loss calcs.......  I have 2 upstairs bedrooms, one is a spare bedroom and the other is our office/computer room.... I spend a few hours a day in the computer room but the other is pretty much just our spare room....  Hypothetically speaking, is it more efficient to treat these as their own zones with thermostats and zone valves and not heat them when not in use, OR have them run on the same zone as downstairs and shoot for more of a CONSTANT circulation and let the heating system just kinda Purr along????  Im wondering how much Heat is lost travelling up the hallway stairs to these rooms if i leave the heat off when not occupied?????  they get down to around 64 ish while i want to maintain 70 downstairs???  is it more efficient to have these rooms heated and NOT lose heat traveling upstairs to the cooler rooms????  LOTS to PONDER??? Running a small buffer tank, im pretty sure i can have the system dialed in for the best efficiency as possible

    Thank You all
  • SWEISWEI Member Posts: 7,356
    More zones

    always equals more installation expense, more complexity, and greater likelihood of short cycling.  If done with pumps, it also results in more electrical consumption.  It sometimes results in greater comfort.
  • NYplumberNYplumber Member Posts: 487
    Knight WHN

    If you like tinkering with water temps, want a lot of on screen info, and a boiler you dont need a high head pump, go for the Knight WHN.

    I service A LOT of equipment, From Munchkins to TT to working on Viessmanns and NTI's. My favorite is the WHN. I was going to go with the new 222F for my home, however with not seeing Viessmann at AHR and the lack of on board options (whn has three temps, can see percentage of fire, ramp delay, anti cycling, high fire cap for oversized equipement, etc.) I have gone back from being a Viessmann fan to a WHN fan boy. The 100-W still offers great packaging at a good price so for combi units on a tight budget for quality and space I will opt for installing those.
  • TinkeraTinkera Member Posts: 15

    Was thinking of Thermostatic heads on the manifold controlled by thermostats in the 2 unoccupied rooms..... Do you think its more efficient to just heat those rooms as well as the downstairs and just let the system hum along condensing the whole time?????  Would I lose less heat from migrating up the stairs to the unheated rooms????  If it is Actually more efficient to have the whole house cruising along at 70 and the boiler just purrs along, that sounds like a GOOD plan to me.... I will be replacing ALL the radiators with panel rads and trv's sized for 130 water temps.....
  • TinkeraTinkera Member Posts: 15
    Knight WHN

    Thanks for giving me your Real World input..... I really like the Specs and Controls listed on the knight, but posted here to ask Everyone's opinion.....  The Knight sure has ALOT more going for it than the WM Ultra Series 1 that i put in 10 years ago......  I Will Certainly Enjoy this project now that I have the time to Do it correctly...... Plan on doing it in the Spring after we get out of this Awful winter we are having.....  Will post lots of pics and also pics of the ultra boiler when I carck it open and see how bad it looks.....

  • RobGRobG Member Posts: 1,850

    I'm with SWEI, I would go with the WHN055. I would rather see a boiler sized on the lower end than the higher end. Heat loss programs are designed to add in a safety factor. Ask Mark Eatherton, according to him, he undersized his boiler (I don't remember what brand) and has yet to utilize its full output. I would increase the domestic storage and do away with the buffer tank. Just don't do micro-zones and you will be fine. All the better if you are sizing the radiation for one water temp and trv's, no zoning at all.


  • TinkeraTinkera Member Posts: 15
    edited February 2014

    Hmmm,  Boy you guys are gonna get frustrated with me..... LOL...... its tough to teach THIS old dog new tricks...... Tough for me get my head wrapped around the WHN055 boiler.....  I thought I had it figured out with the 085 and a buffer tank..... More Mental Gymnastics for me Now.....  Is there a Semi Accurate or Semi Guestimte way to figure heatloss for a finished basement?????  I have the slant fin program and nothing in there for it.... I have several books too but none seem to mention how to do the math or factoring for a basement.... Whole basement has wood framed walls and sheetrock with r11 insulation.... Ceiling has drop ceiling and R19 in the joist bays.....  Basement is about 6 to 6 1/2 feet below ground so not too much air infiltration..... was built as an apartment and now my Daughter is back living with us.... No one said they were supposed to come back after they left... HAHAHAHA....   Also has 5 small windows and an outside entrance door.....  Any calculations or math you can give me would help me maybe narrow down my heatloss even more accurately.... From a Practical or efficiency standpoint is it a good idea to have the boiler running at its TOP end on Design temp days????  I know not every day will require the boiler to be Design water temps???

    Thanks for helping this OLD DOG.......
  • hot rodhot rod Member Posts: 7,094
    basement load calc

    is a module in the HDS design software that Siggy developed. Free trial demo at Not sure how much you can do on the demo version?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    The magic is in hydronics, and hydronics is in me
  • TinkeraTinkera Member Posts: 15
    edited February 2014
    Load Calc

    Wow, Thank you Hot Rod, I have Siggys newly released book edition and planned on ordering his software in the spring to size and set up my tubing runs and circ.... now that i know this software has heatloss too, i will order it in the next week.... Thanks for your help..... This is perfect timing...... will compare these calcs to the slant fin calcs too.....

    Thanks again
  • Mad DogMad Dog Member Posts: 3,183
    If cost isnt too much of an issue.........................................

    You cant do better than a Viessman. After that Triangle Tube. Although many expressed GREAT fears about the Buderus GB Aluminum block and HX, I still stand by them. As long as they are serviced (even every other year works) properly. Mad Dog
    To learn more about this professional, click here to visit their ad in Find A Contractor.
  • clammyclammy Member Posts: 1,996
    low temp n panel rads

    I have the same set up as you are thinking on doing .I used buderus panel rads model 22 w trv and oventroupe isolation valves w a built in by pass .I did a home run systems using 1/2  pex al pex w a upionor tru classic manifolds w flow rate indicators and a califee hydro separator..It runs off the odr which is set for max temp of 130 at I believe outdoor of 10 which we hit and went below this winter and the house still held temp,I am using a munchkin t80 2nd revision and have not had any issues after bout 8 years or so .I found the buderus panel rads easy to install and don.t forget the towel warmers for the bath they are awesome and there nothing better .I have another panel rads system I installed using a peerless purefire and buderus panel rads same mainifold and home run system using a 30 gal boiler buddy works great never short cycles on the shoulder days  and  it is a low temp running 140 at 10 I would add one  to my system except it's to tight for room ,this system also is using a wilo eco circ which runs off a ranco etd unit did not like the constant circ opt on the boiler way to much running temp lose though the heat exchanger .As for a stat I used a white rodger if380 temperature averaging thermostat using 3 sensors being the home was 3 stories and had some issues with a existing baseboard zone that could not be changed ,Do your research and find a boiler with the lowest turndown or low fire with a boiler buddy your set remember to installa good air elimator and a y strainer on your return to the boiler .peace and good luck clammy
  • A modest suggestion

    Depending on the condition of the old boiler, could it be left in just to fire during design day temps, or handle the DHW?

    Then you could have a much smaller new boiler, setup like SWEI's asymmetric systems.--NBC
  • TinkeraTinkera Member Posts: 15

    Thanks for all the help and suggestions........  I was looking into the Viessman also and will see how the budget is after doing my taxes this year...... That is Definately the Cadillac...... Plan on getting the boiler and boiler piping with the indirect and buffer tank up and running in short order and then spend the rest of the spring into summer retroffiting the new panel rads and alpex tubing.... That will take some time and grief as all the rooms are finished and will require some demo work to snake the tubing..... Also will probably end up with 1 or 2 rooms with basebaord that will have to stay, may be way too much effort demo wise to retrofit those rooms..... Baseboard is way oversized in those rooms so i may be able to get away with it........  Clammy, i may pick your brain a bit if i can when it gets closer to setting the system up....... im curious about your thermostat and room sensors?????  You seem to have your system ironed out and im trying to set mine up very similar to yours..... Would LOVE to consider the 2 boiler setup but have NO ROOM in the boiler room.... its very tight as it is......

    Thanks to Everyone for the help...... 
  • clammyclammy Member Posts: 1,996
    simlar set up

    I have a similar set up w baseboard and could not remove it nor get a panel rad or new piping  so I did some creative piping and use of zone valves and a stat for some type of control for those rooms being the rest of he home used trv s and worked off 1 stat and 1 ecm circ  ,If you have to keep the base board think of maybe removing it and upgrading to cast iron definitely worth the investment and heat retention  .When you finally pick your boiler look at the low fire rate  and your projected heat lose on the shoulder months and that should help you decide weather or not a buffer is necessary remember those panel rads work great with a wide temp diff and a buffer tank may offset that difference as for what the boiler is seeing as a return temp as compared to the system return also don't rule out a 2 pipe reverse return piping system with a ecm circ and possibly only a 1inch main you would have some water volume from the piping and may not need a buffer tank .plus you would save some coin on manifolds for a home run system I know I spent close to a grand on manifolds alone  and in retrospect if I where to redo it  I think I would have done a 2 pipe reverse return system but that is just me and I keep that one in my tool bag brain.I do see the pluses of buffer tanks though especially when you get to mirco zoning or smaller zones of radiant(smaller temp diff on radiant systems) especially in the shoulder months .But with a low temp panel rad system or at least the one s I have designed and installed there really is not much short cycling on the shoulder months but I program the boiler limits to operate at a 30 td which seems to do the trick except for those small radiant zone . hope this helps you out peace and good luck
  • TinkeraTinkera Member Posts: 15
    Similar set up

    Will be saving this whole post for when i start in the spring.... Thanks Clammy for the input.... I may replace my fin tube with either cast iron or maybe that Smiths Environmental Low Temp Baseboard..... That looks like a Nice Low temp alternative????  The baseboard is in my two upstairs bedrooms, one is vacant and other room is used as my office space which i only spend a few hours a day in tops...... Maybe set up these 2 rooms with their own stats and zone valve them off the same manifold????  might be nice if i sell the house in the future to have the 2 upstairs bedrooms on their own stats.... maybe a nice extra feature for resale????

    Thanks again
  • IronmanIronman Member Posts: 3,550
    Smith's Low Temp BB

    Just did a job with Smith's. A couple of comments:

    1. The product works well with low temps as advertised.

    2. It can be much more difficult to pipe in depending on the type of construction, particularly very old homes. Remember, you have to Tee into parallel tubes so the riser pipe has to be perfectly plumb.

    3. The element snaps into the back housing tightly and doesn't give any play. This again can make piping more difficult.

    4. There is no damper in the unit and no space for a TRV. So, output cannot be regulated.

    5. Don't mix them with old BBs on the same zone, unless you want balancing and temp swing issues.

    In your case, I'd go with your original plan of panel rads with TRVs. Much easier to install and temp regulation at every rad. Use a delta P circ like the Alpha or Stratos and you'll have a great system. Get the reset curve dialed in right and you won't need a stat. Just jumper "T &T" and let the TRVs and the boiler handle it.

    I'd also recommend the WHN055. If you need more domestic (probably don't), increase the size of the indirect, not the boiler.
    Bob Boan

    You can choose to do what you want, but you cannot choose the consequences.
  • TinkeraTinkera Member Posts: 15
    Smiths low temp

    Hi Bob,

    Thanks for your input on the Smiths Low temp.....  I was considering these to replace my existing baseboard in 2 upstairs bedrooms.... both these baseboards are piped with supply and return looped on top of the element and both coming out the same endcap into an attic crawlspace..... both bedrooms are piped this way and both fed by Alpex.... im hoping this will give me the flexability to put the smiths in place????  To panel rad one of the rooms may involve a bit of demo work into the ceiling downstairs.....  Will have to see what i can do with the most minimal amount of demo work..... All the main floor rooms are easier to retrofit cause i have a drop ceiling in the basement so piping is much easier.....  Thanks again for your help and real world experience...... Alot has changed since i last did this work.......

    Thanks again
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