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Triangle tube and taco sr 506

wrxz24wrxz24 Member Posts: 292
Hi all,

Just had a tt 110 trimax installed t o replace a ci boiler. The installer did a swap out using all of the components on the existing boiler but I had him install a dirt separator. The relay switch board is the tac sr 506 for baseboard and high mass radiant heat.

My question is this, to have the ability to have two separate heat curves for baseboard and in floor radiant, do I need to get the tt external controls to replace the taco?

Thanks in advance


  • heatpro02920heatpro02920 Member Posts: 991
    get a good tech out there

    How many radiant zones and how many high temp zones do you have?

    I would use 2 separate zone controls, 1 for radiant and one for high temp, but the tt will revert to high temp if they both call at once, so you have to make provisions either making sure it doenst happen or mixing when it does... so you radiant doesn't get overheated... When I have low temp and high temp {beside DHW, which can be handled easily with priority} is run the low temp off of a plate exchanger ran by an aquastat, so the 2 systems never mix..

    In other words a plate exchanger with an aquastat that calls water to circulate when it needs to warm up, on the other side of the PE your radiant has its own, water feed, purge stations, expansion tank, and circs that run like a separate system... In my experiences this is the most trouble free design, I would rather have this than mix....
  • wrxz24wrxz24 Member Posts: 292
    3 high mass radiant,

    Which includes garage floor and 3 baseboard whic includes above the garage and not hooked up yet.

    So you wouldn't use the tt optima? So what specific controls would you get? Thanks in advance.
  • JStarJStar Member Posts: 2,752
    edited May 2013

    You will be best off with a Primary/Secondary piping arrangement AND a mixing valve on the the low temp radiant.
  • CMadatMeCMadatMe Member Posts: 3,066
    Taco I-Valve

    Should be two independent heating circuits. Let the TT reset off the high temp and add a Taco I-Valve to reset the radiant. Separate zone controls.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • heatpro02920heatpro02920 Member Posts: 991
    A lot of guys are going to

    recommend mixing, and there is nothing wrong with that, I installed many mixing systems, but I prefer to use plate exchangers...

    as Jstar said the boiler should be pipied pri/sec, I don;t think I have seen any multi zone 110's not piped this way since it comes with the pump built in.

    What are you using for DHW? is it an indirect or is this an excellence model?

    and since you have an sr control I a take it you have 6 circulators...

    OK, so if I were doing the job, I would use 1 SR504 , 1 SR503 , and 1 johnson a419 .

    I would also install a plate exchanger with the a419 calling in the extra 4th zone on the sr504, then I would use the sr503 to control the 4 radiant zones completely separate from the high temp zones...

    the only reason I'm not super fond of the dual temp settings on the trimax is because it overrides itself when the high temp zones call. I think it would be much better to stay low temp until the low temps were satisified and then switch to high, or put it on a timer and alternate...

    The reason I am not a fan of mixing low temp radiant is because I owned a house with this type of system, dont as rite as you can do it, and I always noticed the temps much higher than they needed to be, since the high temp zones and dhw would often return hotter than I wanted the radiant.... So I wanted 98* for my floors, the boiler made 180 and my returns only came back around 150, so how does mixing 180 degree water with 150 degree water get you under 100* .. I have done and tuned many systems like this, its cheap fast and some wont notice the difference, but when I changed mine over I can tell you first hand the boiler ran less, the energy bills dropped but most important the house was comfortable like never before....

    Any qualified tech should be able to design the system, it does take a lot of materials and you still need one mixing valve on the boiler side of the plate exchanger {sometimes}. but when its done, it works very well... For mod cons I like to run the return water from the high temp zone through the plate exchanger just to cool the return temps down..
  • wrxz24wrxz24 Member Posts: 292
    Total zones is 6

    2 baseboard and 3 radiant. The other zone is for the indirect which now is separate from the rest. Sorry for the confusion. I am buying the parts myself. Thanks again Heatpro and all.

    I do already have the mixing valves from the old system. They would be my protection if I went with the optima controls. So you are saying I would not need these if I went with the separate controls. Would they have to be removed?
  • heatpro02920heatpro02920 Member Posts: 991
    NO you will need these if you go with separate controls

    You would not need them if you went with a plate exchanger/radiant system.

    Its hard to explain, there are so many different ways to pipe what you have its easy to get lost in it..

    It really depends on you, you got a great boiler, and there are a ton of options for the install, the biggest thing you have to decide is what you want to spend, the moon is the limit...

    Webstone makes everything to make it a really impressive install...

    5FK4-TTS for the near boiler piping

    Then you can use their purge tees for each zone you pull off and do the same thing on the opposite side of the plate exchanger {running it primary secondary also, sometimes a storage tank works out great too depending on the loads of your radiant and the size of the plate exchanger....

    But that will get expensive fast, I did an install using all of there components about a month ago, the cusotmer asked for it by name and liked the look, it was a tt175 and it added about 1200 to his job, but Ill tell you what, it saved me about 6 hours of labor {which I didnt adjust the proposal for but did adjust the bill after I the job was done, he was happy} and honestly the job looked really good, very impressive, makes it look like a kit...
  • wrxz24wrxz24 Member Posts: 292
    The way you described sounds great but...

    I guess I would like the least expensive way at this point but still get good results. The boiler is an impressive unit, that is for sure.

    Can I keep the sr 506 and remove the radiant from that and buy a sr 503 for the low temp radiant? Any thing else to get the two separate curves working?

    My system before, the main radiant ran most of the time. The upstairs baseboard didn't run as much and if it did, it didnt run long, because we have a big opening to the upstairs balcony and the tstat is in the hallway and not the bedrooms. Thanks again
  • heatpro02920heatpro02920 Member Posts: 991
    edited May 2013
    that will work just fine

    what temp was your radiant designed for?

    I would setup your high temp loops to work as low as they can, maybe 140- since you say they dont run much... maybe do a quick heat loss and add up how mcuh board you have in them zones....
  • CMadatMeCMadatMe Member Posts: 3,066
    The Simplest Cost Effective Solution

    Add a Taco I-Valve and a 3 Zone Relay.

    Next price level solution, add a Taco RMB-1 and a Zone Relay , or if you like the HX idea a Taco XPump Block and a Relay.

    The first solution is the most cost effective way while giving you everything you want without crazy labor. Your not gaining anything by the TT control doing 2 curves. Triangle missed the boat on this. They should have labeled them heating circuits and let the boiler control a 3-way modulating mixing valve for 2 temp systems.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • wrxz24wrxz24 Member Posts: 292
    so keep the sr 506 and

    get which relay? the sr 503 and wire that to the CH2?

    As for the my radiant zone, on the absolute coldest days, 120 degree water does just fine, that would be my setting for my mixing valves if I go this route. I was never told the design temp when I had the house built in 2005. That is why I repalced the boiler, grossly oversized and never set up correctly. The original zones were all set to get 85degree water and that wasn't cutting it. Add a lot of Solar gain during the day, my morning temp could be 6 to 7 degrees below the t-stat..
  • CMadatMeCMadatMe Member Posts: 3,066

    You could just use the existing Zone Control and just use CH1. You don't need to use CH2. Set the boiler reset for the high temp and let the I-Valve Reset for the radiant. See attached.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • wrxz24wrxz24 Member Posts: 292
    Not sure i understand.

    How is this better than a separate control in your opinion? I know you said tt dropped the ball on the separate heating curves.

    The reason I went this route was because of that and the fact that my high mass concrete is getting the most from the boiler. Thanks
  • CMadatMeCMadatMe Member Posts: 3,066

    The I-Valve has built in outdoor reset so it is a control. You wouldn't need to change your zone control either. Simple cost effective and solid solution. The boiler will still be resetting off the baseboard curve.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
  • heatpro02920heatpro02920 Member Posts: 991
    the boiler will still reset on the baseboard curve

    I think that is what he doesn't want Chris, but your solution will be by far the most inexpensive... and will work....

    can you take a picture of your piping for us? I'm pretty sure I know where you are coming form, but I have another idea...

    As far as just heating to say 100 for low temp radiant and 180 for board its only going to work with the trimax until the bb zone calls... I have another post on here somewhere where I explain a job I did that installed a zone control with an extra zone and wired the second one into the first controls priority control, so when the low temp zones are calling the high temp zone could not call, but this raises a problem. If the low temp radiator zone is close to design conditions and doesnt shut off for a long time that high temp zone is not getting heat, SO if that is something you may be interested in its an option...

    You are essentially wiring the low temp zone relays end switch into the high temp zones priority circuit so when one of them is calling the high temp zones wont call. I have done it and it works, it works great if the high temp zone is second floor {which with radiant retro is common} since heat rises, and when you use programable t-stats at night the first floor shuts down and the second floor come sin because that is where the bedrooms are....

    just something to think about...
  • wrxz24wrxz24 Member Posts: 292
    edited May 2013
    Here are some

    They are coming back today to pipe in the indirect. At this point, I'm interested in the most cost effective solution. The installer never installed a tt, he does primarily buderus. He brought another guy with him that installs Triangle tubes. I am buying all the parts for this so if you could break stuff down for me, that would be great. Thanks again fellas.

    Sorry the pictures are sideways...I used my ipad.
  • ZmanZman Member Posts: 6,312
    You already have mixing valves...

    Are they thermostatic?You should be able to use the onboard controls on the boiler.

    Do you have better details on how they are piped?

    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • wrxz24wrxz24 Member Posts: 292
    Honeywell am 1 series

    Are the mixing valves. The mixing valves are piped with boiler water and return water to circulator for supply.

    Please explain how I can use the on board controls. That is what I thought I could do when researching a replacement boiler. I didn't know I was going to need different external controls....
  • heatpro02920heatpro02920 Member Posts: 991
    The onboard controls

    for the trimax TT solos are limited to controlling 2 heating zones and 1 DHW load. Anything more and you will have to use external controls...

    For the most part they work well, but the only thing I don't like is that it reverts to high temp as soon as a high temp zone calls for heat... I would give trainagle tube a call and ask what they do for this situation, Im sure its going to be mixing, but who knows maybe they have a way to change it so the hgih temp zones just opne until the low temps are satisfied and then switches to high temp...
  • wrxz24wrxz24 Member Posts: 292
    edited May 2013
    So I could

    Essentially take my most used/largest radiant zone off the external relay and connect to the ch2 control on the boiler without having to get an additional external control. I think I could live with this for the time being. Like I said, this low temp zone often runs by itself. The other radiant zones are for bedroom and garage.
  • ZmanZman Member Posts: 6,312

    Your mixing valves are thermostatic. They will always adjust to the same temp no matter how hot the primary loop is.If you install another relay to get a separate TT for CH2 it will work great as a 2 temp fixed temp system. The outdoor reset will not function optimally. The high temp will work great. The low temp will be pegged at the max temp set on the mixing valve anytime the high temp loop is calling. This is the simplest way without repiping.

    Triangle tube had an add on for the old controller that would control a mixing valve as Chris is describing, it might be worth a call to tech support. Otherwise Chris's Ivalve solution would work pretty slick.

    Heatpro, are you talking about a plate exchanger and a separate closed loop with it's own expansion and all the fixings, just to lower the temp in one loop? If so, please put down the crack pipe. If not, oops, never mind the crack comment, please explain.

    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • heatpro02920heatpro02920 Member Posts: 991
    edited May 2013

    you wrote They will always adjust to the same temp no matter how hot the primary loop is.

    so when you want 98* water in your radiant loops and have a 180* supply temp, 78* coming out of the radiant, and 160* return temp {from your high temp system} how is mixing any of them together going to make 98*? You figure that out my friend and I will eat the crack pipe... I know when the radiant is cold it will mix rite but at some point the loops will run hot, My office building is all radiant except for hanging garage units for when the doors open {We designed a control to run the fwa units when the temp drops faster than 5 degrees from the t-stats setting then it runs 3 degrees past}... and when the doors are left open and them fans are running the temps in my floors get way too high.... I have since switched to separate units to power the radiant and the coils, but before I did that the floors would overheat... Customers will hardly notice I'm sure unless they are watching the gauges, but I have gotten service calls that the house goes way past t-stat setting, and that is just because the water in the floor was too hot...

    you also wrote- Heatpro, are you talking about a plate exchanger and a separate closed loop with it's own expansion and all the fixings, just to lower the temp in one loop? If so, please put down the crack pipe. If not, oops, never mind the crack comment, please explain

    First yes that is what I am proposing, I have done it many times, and in my opinion easily the best option {sure more work and costs more, but you spent the money an radiant go all the way},it remedies all the issues that having one heat source make 2 separate temps can come up with... {cold returns , for cast iron boilers, overheating rad loops, faulty mixing valves, ect}.

    Next this is not just one loop, the OP explained it is 3 loops that are the primary heat for the building...

    How I would do it is this way.... Let e explain this maybe then the benefits will make more sense...

    Wire the rad zones to one zone control and the high temps to another, wire the end switch for high heat as you would normally, but the end switch for the low temp panel gets wired to an aquastat in the PE, then onto the low temp terminals on the trimax. so when the low temp zone calls it goes through the aquastat that is set at say 115 {of course depending on size of PE and temps you want, temps are just for example}. Now set the trimax low temp zones temperature at 130, wire the circulator for the Plate Exchanger to the trimax's low temp circ terminals..

    Now when the radiant calls alone the boiler will heat to 130 {set its curve accordingly of course}, then when the high temp zone pulls in at the same time the boiler will go up to 180 BUT the plate exchanger will only take what it needs.

    Now pipe the radiant as a separate closed loop system, and the other side of the plate exchanger can be piped with a mixing valve, through return, or just as another zone what ever you want...

    The moral of the story is, you will NEVER over heat your radiant {so comfort and equipment is great} you will still only have to heat to low temps, and get low return temps. Cost is higher of course due to extra materials, plate exchanger $180, watts install kit $160 {1" bronze air scoop, water feed combi, exp tank, ect}, extra circ $160 {bumble bee}, fittings $125, aquastat $60 johnston 419a digi, so an extra $600 or so, but when its done it is definitely pretty and works very good... PLUS, I like running my radiant at a lower press than the rest of the zoznes, especially when they are below grade and the high temp zones are hanging or third floor that needs much more pressure.... Another good thing about having them separate closed loops is if you want ot just run antifreeze in your radiant you can, this is popular with basement slabs and garages, now you don't radiant the boiler and rest of the house just the floors....

    But anyway, zman, maybe I am on crack, that made me laugh and I have had a terrible morning, I made myself tea and noticed I only had 1 tea bag left {I just reach on the container, never look, its always too early to open my eyes}, then I spilt the tee, I have never dropped a coffee cup in my life, of course I do it when its the last tea bag!!! Son of a ****, so now I had to have my son go to dunkin donuts and get me this terrible tea until my wife goes to the tea store or where ever she goes for that stuff today... Terrible saturday morning, terrible...

    PS I do like doing things different, I know that, but when you start to add it up, them mixing valves arent free, so with most systems the cost of the plate exchanger method is almost washed by not having to buy 6 mixing valves....

    zman, granted, if this was one zone, yes, that would be SILLY. But he stated 3 high mass radiant zones that are his primary source of heat... So to me it would be worth it... With one zone saya basement or garage, then sure wire it in and chances are it wont run enough to care...

    I hope this all made sense, I haven't had "MY" tea this morning and I couldnt even power half way through the D&D stuff... Man I wish I had some "crack". then I would be on top of my game for sure... lol

    But in all seriousness, if you are staying with the mixing valve system {which is the best choice for budget and easyness}, dual controls are a must.

    I hate that I have pirated your post a little here so I offer you this, a drawing I made, it should work for you. I did this before a little different used a psu and rib {which I didnt draw in} that allows to pull both controls in with one end switch, but this should be simple... I hope this makes sense, and Im sure there are other wallies that can improve on it, I welcome this and love to learn, anyone have any ideas on how to make this better?????

  • ZmanZman Member Posts: 6,312


    I was hoping you would see the humor in the crack comment. I will let you know if I find some.

    My point was you could have some control over the low temp utilizing the existing valves. When the high temp loop is calling, the only low temp control you would have would be a fixed maximum temp. Not ideal, but inexpensive.

    I think Chris offered a decent budget solution with the I valve.

    In my opinion the absolute best alternative would be to use a Tekmar TN4 system.

    We recently did one that had a tekmar 423 controlling 2 modulating boilers. It can control up to 4 mixing valves at 4 different setpoints. The boilers will always be running at the lowest possible temp and the floor temps are dead on.

    I am still boggled by the flat plate solution. You don't need to isolate the loops, you just need to control the temp. An automatic mixing valve or injection pump setup is much simpler.

    I agree that triangle tube missed the ball on this one. I wonder if lochinvar has a solution on their firetube.

    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • heatpro02920heatpro02920 Member Posts: 991

    Tekmar would be a good, BUT, cost wise not so good, did you look at my picture above, whats simpler than that? And he is only out the cost of the sr501 which a $15 rib would also do but needs a little more skill to pick and wire it...

    I guess I have been around long enough to hate mixing valves, although they seem to last much longer when you use no cast iron or steel in the piping, I am not afan of them, sure I have installed my share of mixed radiant with mixers, but I would rather use 2 heat sources than mix and that is a lot more work and costs almost double...

    Sometimes you gotta throw cost and labor out the window for how you want it... Does't always make sense to everyone BUT.. I just hate mixing valves!! I don't even like them in my shower...
  • ZmanZman Member Posts: 6,312
    Different strokes

    Your drawing is a simple solution. It has the opposite disadvantages to my solution. If limited high temp performance is not an issue,it should work fine.

    I have had good luck with powered mixing valves. I  also see an advantage to single appliances and indirect tanks.

    This is what I like about The Wall. There is more than one right way. Always learning....

    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • heatpro02920heatpro02920 Member Posts: 991
    Exactly true Carl

    Thats why I always say install what your contractor recommends, once you find an installer you are comfortable with, use him.. I am much better at installing a Buderus GB or a TT than I am at installing an alpine or Veissman. I'm not saying I can't install an Alpine as good as anyone else, but there may be a little trick that they guy doing 3 a week knows and I don't...
  • wrxz24wrxz24 Member Posts: 292
    By all means

    Thanks for all the advice, my head is spinning. I think for the time being, I am going to try the next winter by wiring my main radiant heat zone that does most of the work to the ch2 inboard of the tt. The other radiant is for my bedroom and bath, and then there is the garage where I keep at a balmy 50 degrees. I will keep these on the sr506 controls and mix them down when the baseboard calls. At some point, I want to make a change for the better, but need to save some more ducklets to get there. So my question is this, can I remove one zone from the controls and wire that zone to the tt for a low temp zone?
  • ZmanZman Member Posts: 6,312

    Sorry about your head.  Some off these posts go pretty deep.

    Yes, you should able to wire one t-stat and one circulator directly to the boiler.

    You might be surprised how low you can run your hot loops. It will take a bit of experimenting.

    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • wrxz24wrxz24 Member Posts: 292
    Thanks Carl

    I will do that for now. I know I will be able to lower my hot loops well below 180. Eventually, I will do the external controls for the different zones. I like the idea of switching the priority to low temp vs high temp though. It may work in my situation. Heatpro, thank you for posting the diagram, I hope it will be o.k for me to contact you when I get around to making the changes.

    But to conclude, I still could keep the 506 control and add more controls like in the diagram? Thanks again fellas, I admire what you guys can do. This PE teacher from Vermont appreciates it.
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