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    Pumping away ? I must have something messed up! Help (73 Posts)

  • Badger896 Badger896 @ 10:38 AM
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    Pumping away ? I must have something messed up! Help

    So new boiler install and i followed the pumping away guide to avoid pressure issues but something is not working. Piped as follows boiler, ball valve, air purge with vent on top water fill and expansion tank on bottom, inlet side of primary pump,(taco 0011) ball valve and then back to the boiler. piped as primary secondary system. two secondary loops with closely spaced tees and each have their own pump, one with another taco 0011 and the other small loop with a b&g?
    So with the boiler and pumps off the static pressure of the boiler is at 12psi. turn the boiler and pumps on and the pressure climbs and climbs until it eventually pops the p/t valve at 30psi. i have eliminated the press red valve and the bypass valve by closing the system off between the p.r.v. and the boiler with a guage on the prv side the pressure maintains and does not climb until i open the valve to the system and the pressure starts climbing again.
  • SWEI SWEI @ 10:58 AM
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    30 PSI

    is 69.3 feet of head.  The 0011 maxes out around 31 feet.  Unless you somehow managed to pipe the two pumps in series, and even that is dicey, I'd be looking at a leaking indirect or tankless coil.
    This post was edited by an admin on March 8, 2014 10:59 AM.
  • Badger896 Badger896 @ 11:03 AM
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    Got a pic if it helps

    this is it
  • SWEI SWEI @ 11:28 AM
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    Grundfos pump at lower left

    does that feed the indirect?  If so, try powering it down and valving off both lines.

    0011 is an unusual selection for a primary loop -- what size is the boiler? 
  • knotgrumpy knotgrumpy @ 12:49 PM
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    Might just be the picture but it almost looks like you are feeding supply water into the vent of the pressure reducing valve.
  • icesailor icesailor @ 11:38 AM
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    I don't know what the reason is however,
    Is the primary pump (011) pumping INTO the boiler or out?
    The two secondary pumps are not connected the same. One is supply to return, the other is return to supply. It depends on the flow. They both should (IMO) be the same.
    It is possible for any two pumps to "multiply" and cause the pressure to rise but also cause the suction/lower pressure end to allow the pressure on the PRV valve to go less than the set pressure, allowing the PRV to add water.
    Unless there is a reason that you can't, flip one of the secondary circulators so they both go in the same direction off the closely spaced tee loop, and see if it improves.
    Does the pressure rise if just one circulator is running? It should be running with the primary pump. Switch the running circulator. Does it add water or stop?
    The few boilers that I did, I always tried to have places I could install cheap temperature/pressure gauges so I could see how the system was behaving. If there is a boiler drain connection on either side of the circulators, you can determine what is going on in the system.
    IMO, if the primary pump is in backwards and not pumping into the boiler, the pressure can reduce between the boiler (with high resistance) and the PRV.
    The system in the pressure isn't like an open system like a potable water system. If you understand about Hypertension in humans, it is similar. If you cut yourself, the pressure drops as you lose blood. and the heart pumps harder to keep the pressure up. If there is no loss, the heart can raise the pressure with the same amount of blood. That may be confusing. Like compressed gasses in water under pressure.
    Somehow, the pumps are multiplying. You need to figure out how. Its in the locations and which directions they are pumping.
  • knotgrumpy knotgrumpy @ 12:46 PM
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    Another Pic

    Can you take another picture of the piping near the inlet to your primary pump and the pressure reducing valve?
  • Gordy Gordy @ 11:24 AM
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    Circ orientation

    Are you sure all circulators are pumping in the right direction?
  • Badger896 Badger896 @ 11:27 AM
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    made sure they are all going in right direction.
  • Badger896 Badger896 @ 11:30 AM
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    Circulator sizing?

    Is it possible the taco 0011 circulator is oversized for the primary loop and as mentioned before the pumps are in series or something??
  • Badger896 Badger896 @ 11:35 AM
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    not sure what is meant by indirect (it is one circuit feeding fin tube).
    the boiler is 175000.
  • SWEI SWEI @ 11:38 AM
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    Pumps and pipes

    I see two green pumps, presumably Taco 0011's.  One is on the primary loop, the other off a set of closely spaced tees, probably feeding your baseboard.

    I see one red pump, presumably a Grundfos, off a second set of closely spaced tees. What does it serve?

    If all you have is one zone, it's quite likely you don't need primary/secondary piping at all.  How much pipe head does that zone have?  How much fin tube of what type?  Was a heat loss calculation done?
    This post was edited by an admin on March 8, 2014 11:39 AM.
  • icesailor icesailor @ 11:52 AM
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    Pumping Away:

    I think you got confused with the concept of "Pumping Away".
    It never happened to me and I don't agree with the total concept of pumping away from all boilers. These "mini-Boilers" call for the primary pump to be pumping INTO the boiler so that you don't get flow problems through the boiler. If the primary pump is pumping away, rather than into, check the installation manual and see if they don't require that pump to be pumping into the return of the boiler. Not pumping OUT of the supply. The exception to the rule of Pumping Away.
    Many years of perfectly working hydronic systems are pumped with the circulators on the returns so they pump into the boiler, with the least amount of restriction. The ones that have "Issues" usually have other unrelated problems. Like oversized pumps.
    I know that ME considers me a Heretic, but I have never installed a circulator on the supply but only and always on the returns with the fill into the bottom of the boiler into the coldest water. I have NEVER encountered any of the problems I see here all the time. But I sure see a lot of problems with circulators on the supply's coming directly out of boilers with air issues and the need for microbubble scrubbers. That circulator may have to be moved to the return and pumped INTO the boiler.
  • SWEI SWEI @ 12:15 PM
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    Pumping Away

    from the Point of No Pressure Change is what matters.  The short version is that you pump away from the pressure tank.  The firetube heat exchanger utilized by Triangle Tube has almost no head loss -- I've attached the curves for the 175 and 250 below.

    Just because they show a curve for a 0011 doesn't mean you should actually install one.  There's a funny bit of pipe detail at the upper right-hand corner of that loop I can't quite see -- is it an offset in the Z dimension with a couple of tees?

    I doubt you have more than 40 feet of developed length in that primary loop.  If it's 1-1/4" copper, you're pushing at least 24 GPM and 6 FPS there.  Believe it or not, I'd probably use a 006 for that.

    If I were starting from scratch, I'd dispense with the primary/secondary piping altogether, install two zone valves and use a single ECM smart circ.
    This post was edited by an admin on March 8, 2014 12:16 PM.
  • Badger896 Badger896 @ 12:27 PM
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    z dimensio

    the primary loop is 1-1/4" , there is about 20' straight pipe and (7) 90's.
    do you think changing the pump to a 006 will help?
    Sorry, im still learning.
  • SWEI SWEI @ 12:31 PM
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    can get expensive when you are paying for the parts.  Before you start swapping them, get the system properly designed.

    What is your calculated design day heat loss?

    How many feet of what type of baseboard in each loop?  How are they piped?  Do the emitters in each room have any relation to the room's heat loss?
  • Badger896 Badger896 @ 12:46 PM
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    The install was a rush (previous boiler leaking like crazy) due to the fact that it is in an assisted living house and could not go without heat. The boiler is their only source of heat. You know, never have time the first time but always have plenty the second.
  • Badger896 Badger896 @ 11:52 AM
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    ok so ghe primary pump is pumping away from the boiler (i.e. it is on the supply of the boiler) it the leaves the pump and goes to the first set of tees and the 0011 is also pumping away into the baseboard heat and returning to the primary loop, the the next set of tees (bottom of primary loop) have a grundfoss pumping away into baseboard heat and then returning to the primary loop and returning to the inlet side of the boiler.
  • Badger896 Badger896 @ 12:01 PM
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    i guess i dont understand how moving the pump to the return will help, with the primary loop isnt it in effect in the return and pumping back into the boiler? the fill valve and expansion tank will ultimately end up in the same arrangement the only difference being that the supply side of the pump will see the boiler first and then the two circuits.
    Will that make a difference?
  • Gordy Gordy @ 12:26 PM
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    pressure reucing valve

    I think Ice may be on to it. Quite possible the circ differential is making the fill valve dump into the system.......unless the make up water is off.

    One other thing is x tank pressure properly set?
    This post was edited by an admin on March 8, 2014 12:36 PM.
  • RobG RobG @ 2:18 PM
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    Boiler piping

    On the 175 the primary piping calls for a minimum of 1 1/4 piping, is it? As well with a boiler of that size you must have an awfully large house with ALLOT of baseboard. Is the expansion tank sized correctly? And the manual does call for the pump to be on the supply side, but the fill valve and tank should be on the return or on the secondary side. I'm still trying to grasp why you piped it with two sets of closely spaced tees. Piped that way it will ensure that the second set of tees sees lower water temps.

    This post was edited by an admin on March 8, 2014 2:29 PM.
  • Badger896 Badger896 @ 2:50 PM
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    yes the primary piping is all 1-1/4", the boiler is in an assisted living bldg. there are probably 20 rooms or so. all with baseboard heat.
  • RobG RobG @ 3:10 PM
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    Boiler fill

    Have you tried shutting off the boiler fill valve? Does the pressure rise with it closed?
  • Badger896 Badger896 @ 4:10 PM
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    I did shut off the boiler feed and the pressure will stay at whatever psi (12+). But as soon as you turn the valve back on the pressure will continue to rise to 30psi when it opens the p/t valve. Now if the boiler and pumps are off it will fill to 12psi and stop. As soon as the pumps come on it will start its increase. I feel that the 0011 pump is dropping the inlet side below the 12psi causing the fill valve to let water in ultimately increasing the pressure but according to pumping away and the x tank placement vs fill vs pump it should not let it do that. Obviously I'm confused about what's going on.
  • Paul48 Paul48 @ 4:11 PM
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    The install definately needs work, but the only things that could cause what he has, is the auto-fill regulator, or lack of circulation, or lack of expansion capacity.
    This post was edited by an admin on March 8, 2014 4:15 PM.
  • Badger896 Badger896 @ 4:38 PM
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    Needs work

    Not being a smart @$$ but what else did I do wrong? If I did something else blatently wrong please tell me, I'm not a hack. I was crunched for time, I know that's no excuse but I'm certainly not trying to walk away from it either. Any constructive criticism is welcome.
  • SWEI SWEI @ 4:48 PM
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    Constructive criticism

    requires more information, or we will just be guessing.  I'll repeat myself:

    What is your calculated design day heat loss?

    How many feet of what type of baseboard in each loop?  How are they
    piped?  Do the size of emitters in each room have any relation to the room's
    heat loss?
  • Badger896 Badger896 @ 5:12 PM
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    More info needed

    My boss did the heat loss, but I will find out. I will also look at fin tube in each room. I know that the piping in the rooms has a primary run under the fin tube and each room has its own thermostatic valve tee'd into the primary run. Out of the valve it goes through the fin tube. The piping is original from the 60's or so, it appears that some rooms share a return and others do not, part of the problem is the majority of the piping is in the walls and finished ceilings so it's hard to tell just exactly how much is there and exactly where all of it goes.
    What do you mean by "do the size if emitters in each room have anything to do with the rooms heat loss"? If I understand then yes, the corner rooms have twice as much fin tube as the internal rooms do.
  • SWEI SWEI @ 6:20 PM
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    Sizing emitters

    I make a spreadsheet listing each room with it's heat loss and installed emitter capacity.  From that, we can determine what the required system water temp is and also if there are rooms which are likely to become too cold or too hot when the system is running on ODR.  For series baseboard, a bit of math is added to the spreadsheet to allow for temp drop along the loop.  It's unfortunately rare to find those sized correctly, at least in our neck of the woods.  This is a key component of our initial analysis, and from it come recommendations which are reviewed with the owner(s) before a contract is even offered, much less signed.  If recommended repairs or improvements are declined, waiver language gets added to the contract to protect us.
  • Ironman Ironman @ 5:06 PM
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    Expansion Tank

    There are charts and formulas for sizing the expansion tank. The main factors are the volume of water in the system, the delta T from coldest to hottest water temp and the maximum pressure differential from cold static fill to high limit cut off. You can find the formulas on this site or online.

    That being said, I can almost certainly assure you that a 20 unit facility with a 175k btu boiler and high temp emitters is gonna require far larger than an x30 tank. I would guess it would take at least a 90, but doing the math is the only way to get it right. There is no way to get things right in hydronics without doing the math properly.

    And, I concur that 011 circ on the primary is way too much. The fire tube heat exchanger in the T.T. Boiler has very little head loss and does not require a large circ for that size boiler. Probably a 007 or Grundfos 15-58 would be more than enough. But, do the math and check the boiler manual for the head loss at the required gpm and follow their pump sizing charts. You probably did not need p/s piping unless the second loop off of the secondary has very different temp or flow requirements than the first loop.

    Neat workmanship is nice, but proper design is the foundation everything is built upon. Even on a replacement, the job is not done right without proper design. Except for doing a heat loss calc, the other design factors would not have required more than 15 minutes time if you know the formulas and/or follow the charts in the manual.

    Please, we want you to excel in this trade. So, take some time to learn the math and how to size and design things.
    Bob Boan

    You can choose to do what you want, but you cannot choose the consequences.
  • Badger896 Badger896 @ 5:31 PM
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    X tank size

    So how does an undersized expansion tank affect the pressure on a system? I don't disagree with you at all, that's not the first time I heard it. I understand that if the water in the system when heated has nowhere to go it will increase in pressure. But the pressure climbs up with very little change in temp, and only when the pumps are turned on. Oh and all three pumps always run continuosly. I totally agree that proper design is crucial. I will look for the calcs and charts.
    Thank you
  • Ironman Ironman @ 5:55 PM
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    011 Circ

    The 011 circ is probably throwing too much pressure into the heat exchanger also.

    The expansion tank will NOT "absorb" any pressure created by the circ. That's why it's connection to the system is called the Point Of No Pressure Change (PONPC). The tank will only receive the expanded volume of water that's created by heating it. So, whatever pressure differential the 011 is creating will effect the relief valve.

    It may be a combination of BOTH an under-sized x tank and an over-sized circ on the primary.

    If you have a 007 or 15-58 on hand, it would be relatively easy to swap out the primary circ and see how that effects your situation.

    Regarding the X tank: you will not hurt the system by over-sizing it and you can hook multiple ones together at the same point for more capacity. Just make sure the air pressure on each bladder is the same with no pressure on the water side.
    Bob Boan

    You can choose to do what you want, but you cannot choose the consequences.
  • SWEI SWEI @ 6:23 PM
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    Expansion tank sizing

    There's a bunch of math, but makes it easy.
  • Badger896 Badger896 @ 7:10 PM
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    I did find that before but once again I'm just guessing at the total volume due to the fact I can't see all the piping.
    On another note, from my math you were right in approx 40' equiv in pipe and the head loss should be around 1.5 to 2 for 8gpm but if I'm reading the chart right I'm at like 8fps with 29 or 30 gpm. So if like some of the other posts also suggest in order to get the velocity down with the gpm vs head loss I should move to the 006 pump? Along with possibly increasing the x tank size.
    I appreciate the help I have rcvd
    This post was edited by an admin on March 8, 2014 7:20 PM.
  • SWEI SWEI @ 9:17 PM
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    Boiler circ on P/S loop

    If I were starting from scratch, I would specify a 006, but be prepared to swap that for a 005 if it proved necessary (translation: if boiler tripped off on high ∆T.)   If I did not have either of those on the shelf, a 007 would be a far better choice than a 0011 (and certainly useable until I had the correct circ in hand.)
  • Badger896 Badger896 @ 10:30 AM
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    I am going to try the 006, using the 0011 also explains why my delta is only about 10deg.
  • SWEI SWEI @ 1:28 PM
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    Let us know how it works out

    At least 95% of the boilers we see are overpumped.  While I understand the "lawyers made us do it" mentality used for installation manuals, it's unfortunate that in order to maximize efficiency on a mod/con, you actually have to read between the lines.

    I'm still concerned that your boiler is oversized, but that's a different conversation.
  • Badger896 Badger896 @ 7:10 PM
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    For what it's worth, I am going to try and see if there is a mechanical print available for the building by someone. I know the boiler we took out was 225000.
  • Paul48 Paul48 @ 5:41 PM
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    In General

    I was refering to the things that had already been touched on in others posts.Beyond design considerations, look at the I&O manual, and see how much you varied. They call for the primary circ to pump at the boiler for a reason. It prevents it from cavitating. Is that expansion tank mounted hanging off the side of the pipe, unsupported? Is there any provisions for power purging those loops?
    This post was edited by an admin on March 8, 2014 5:44 PM.
  • knotgrumpy knotgrumpy @ 8:00 PM
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    Are you able

    To take another picture closer to the primary pump/prv/tank?


  • knotgrumpy knotgrumpy @ 8:36 PM
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    Accumulative pressure

    From one of my favorite Dan Holohan stories:

    “Just one of those things,” I said. And we poked around the boiler room some more. And that’s when we spotted the bypass valve. It was up high, between the main supply and return lines. It was just a motorized two-way valve, and it had two operational choices: open or closed. We traced the wiring over to a pressure-operated switch in the main supply line. When the pressure got to a certain point, the two-way valve would open, allowing the water to flow back to the boilers.

    “That’s there for when the thermostatic radiator valves are closed,” I said. “The water needs a place to go because the TRVs can’t talk to the pumps. The pump backs up on its performance curve. The pressure switch senses it, and opens the valve. The pumps now have access to the butt end of the boilers.”
    “And the TRVs are going to be closed more often in the spring and the fall then they are in the dead of winter,” Joe said.
    “Right. And when that two-way valve opens, eighty feet of pump head, or about thirty-five psi, hits the boilers.”

    “Which are already seeing twenty-eight pounds of static head pressure,” Joe said.

    “And that makes the total pressure sixty-three psi.”

    “On fifty-psi relief valves!” Joe said, and he smiled. Problem solved.

    It’s not just one of those things. Not at all. It never is when it’s mechanical. There’s always a reason for things." 

    It's a great story starting with 20 blown boilers sitting in a parking lot.
  • Badger896 Badger896 @ 10:10 PM
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    Accumulative pressure

    So thats what doesnt make any sense to me, why when the valve opens does the head loss go up? why doesnt it go down, you have less restriction in the piping right? so why would the pressure on the boiler increase. according to the charts as the head loss increases the gpm decreases, so if you have less head loss and your psi is about 43% of your head loss then why when you decrease the head loss would your pressure increase??
  • Badger896 Badger896 @ 9:18 AM
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    Accumulative pressure

    Ok, please correct me if I am in error, so let's say that the 0011 can pump at 31ft hd which is approx 13 psi, is this the pressure differential across the pump that it will create regardless of where the pump is on its performance curve?
  • Paul48 Paul48 @ 9:46 AM
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    Wild Goose Chase

    Is this climbing to 30 psi, a slow process? Is the whole system coming up to temp when this climbing starts?
    This post was edited by an admin on March 9, 2014 9:48 AM.
  • Badger896 Badger896 @ 10:10 AM
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    Chasing alright

    But I think I'm getting through the fog. The pressure climbs relatively quick at the start but then the boiler will heat and it takes a bit for the pt valve to pop.
    So I think that if the ponpc before the pump is at 12psi and then the pump comes on and produces a press diff of 13 psi, since it can't add it to the ponpc and there is relatively no head loss in the piping or boiler then the boiler pressure is going to climb to 25psi the water heats the pressure climbs and the pop off spits!!
    It's pretty much the same example in 'pumping away', there's nothing there to gobble up the pressure developed by the pump and the butt end of the boiler sees it.
    There is also a lot of noise from water moving at the lower static pressure until the pressure builds and when the system is walking the line with the pt valve it's quiet.
    I think the noise is coming from the velocity of the water moving and possibly causing the pump to cavitate. Not sure on that though
  • Stephen Minnich Stephen Minnich @ 11:00 AM
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    I pipe

    mod/con boilers exactly how the manufacturer recommends and, if I'm not mistaken, Triangle Tube has the boiler itself piped off the closely spaced tees (as the secondary loop) and the Prestige has very little pressure drop so a 0011 is way too big. I would refer back to how the installations instructions show these being piped.
    It's all in the details.
  • SWEI SWEI @ 11:57 AM
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    TT piping diagrams

    show both options (see p. 21 & 22 in the PTS IOM.)  Direct piping/pumping is covered in more depth during their training classes, but requires proper pump sizing (which is unfortunately more than one can expect from the average installer.)
    This post was edited by an admin on March 9, 2014 12:39 PM.
  • Badger896 Badger896 @ 12:48 PM
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    Thanks for the classification

    Soon I will be better than just an average installer. While I agree that I could have been more diligent in following the manual I also know that books and manuals such as 'Pumping Away' were written because of misinformation from manufacturers (not saying TT's information is wrong).
    The reason I'm here is to try and get help in understanding the dynamics of what I did wrong so I can make it right for my customer. Ultimately preventing it from happening again. I am appreciative of the help I have rcvd.
  • SWEI SWEI @ 1:03 PM
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    Becoming a better installer

    Triangle Tube's training classes are one of the better deals in the business IMO.  You pay a couple dollars for the class, but they spend more than that on lodging and meals while you are there.
  • icesailor icesailor @ 5:41 PM
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    Messed up?

    "' "The reason I'm here is to try and get help in understanding the dynamics of what I did wrong so I can make it right for my customer. Ultimately preventing it from happening again."" "

    You didn't do anything wrong. Wrong is not asking the questions. None of us were born knowing it. We all had to learn. We learn by our life experiences.
    We learn by being stubborn when confronted with a problem that others walked away from. It became a challenge to us. When we figured it out, we learned and become better at whatever we do.
    My wife has an expression. "Life can only be understood backwards. But must be lived forwards".
    If you know more today than you did yesterday, you are having a good day. I learn something here every day. More than anyone will ever know.
    "So many things to learn. So little time to learn them".
  • Paul48 Paul48 @ 11:12 AM
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    Couple Thoughts

    That pump will add pressure based on its curve, not maximum. You are probably
    destroying that pump, which then brings us back to expansion capacity.
  • icesailor icesailor @ 1:09 PM
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    Velocity Noise:

    That noise is from Cavitation where the velocity of the water is slower than the circulator impellor is designed to go. The water is boiling around and in the impellor. When the pressure goes up, the boiling point goes up. The cavitation stops because of the increase in pressure.
    Some old dead Wethead's figured out that pumps on the returns see cooler water and less cavitation.  A variable speed pump in a different location could be a beautiful thing.
  • Gordy Gordy @ 12:40 PM
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    Circs pressure differential

    Will depend on the head the pumps sees. The larger the head loss the greater the differential pressure. If you install a 0-30 psi pressure gauge at the circs inlet, and outlet locations you could use the psi difference to calculate feet of head by taking the psi difference multiplied by 2.31 this gives feet of head.

    Example if the psi difference is 5 psi then the feet of head conversion would be 11.55 feet of head loss.

    As far as your primary, or boiler loop there is enough calculable information you can see to find the loops head and plot on the 011 pump curve chart.

    As far as the system side is the 20 units of base board in multiple floors, or is it a one floor layout?

    So if the inlet side of the circ drops to 11psi the fill valve will start filling the system for as long as the pump is running. But once the relief valve pops the pressure when you shut everything off should be higher than 12 psi. Since the relief dribbles at 30 I would think you would be in the 20 ish psi range until you bleed off some fill water back to 12 psi.

    One of the possible issues with the pump on the return pumping into the boiler is the added differential pressure can pop the relief valve, but usually this happens when the system pressure needs to be higher because of system elevation to get psi over the top.

    So in your case the 011 would have to add 18 psi to the outlet side to pop the relief valve on the boiler.
    This post was edited by an admin on March 9, 2014 12:52 PM.
  • icesailor icesailor @ 12:59 PM
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    Big Pumps/Little Pumps:

    Two pumps pumping on the same pipe  and together and through each other: Big pump pumping into a little pump wall raise the pressure. Little pump pumping into a big pump will not really raise the pressure.
    What I have learned from experience is, the bigger the volume and velocity coming OUT of the pump, the lower the pressure will be going IN to the pump.
    In spite of what the manufacturer says about the primary pump on the supply (pumping away), there HAS to be restriction or pressure drop through the boiler. NO MATTER WHAT!!!. If the fill valve (PRV) is between the suction of the circulator and the source of restriction (the boiler), the system pressure can drop locally (between the circulator and the boiler) to cause the PRV to add water. Shutting off the PRV feed and it not gaining water proves the point.
    To prove my point, take a Watts 1156, connect it to a double hose connection and hose and boiler drains, and connect it to the return of the boiler. Leave the installed fill valve off.
    It won't gain water. If that primary circulator was on the return (in spite of what the manufacturer says), there wouldn't be an issue.
    In the late 1970's, early 80's, I went to a Emerson-Swan seminar put on by Taco and Heatway. I remember Dan telling a story about getting air into a heating system. Someone had a problem job and they couldn't stop the system from gaining air. Someone noticed that they could hear air being sucked into the large circulator through the seal. That's why it needed to be on the supply.
    I don't remember if I agreed with that or not at the time but with all the well jet pumps I ever worked on, if the seal was bad, and the pump was running, the seal leaked water. I thought at the time, or thought later, that if the seal was sucking air, there was too much restriction on the return.
    On Commercial jobs, they use "Circuit Setters" to determine the flow rate. By measuring the pressure differential to determine flow rate in the circuit. If you have 12# system pressure when static, and the outlet pressure on the system goes to 15 PSIG, but the inlet drops to 9# PSI, you have 6# PSIG of head pressure. If there is a PRV valve installed on the suction side of the pump, where the pressure is 9# PSIG, what does the PRV/Fill valve do? Add water?
    Am I wrong?
    I wasn't in application.
    It also sounds like the Expansion tank is way undersized. I mean REALLY undersized. Connect a much bigger tank with the double hose connection into the system and see if the water adding improves. I'll bet it will.
    This post was edited by an admin on March 9, 2014 1:13 PM.
  • hot rod hot rod @ 10:52 PM
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    What size expansion tank

    Was on the former boiler. Probably the new boiler holds less volume so the tank that was on the system previously should work on the new boiler.

    Pumping away from the expansion tank will not cause the fill valve to add addition water IF the fill valve is also connected at that point

    What about expansion tank pre charge, maybe the air charge is gone?
  • icesailor icesailor @ 11:13 PM
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    Expansion Tank:

    " ""I know the boiler we took out was 225000." ""
    This string is getting so long, I can't find anything.
    That "Extrol/bladder tank might barely work on a teapot heating system, but it will definitely not work on a heating system that has a cold start boiler with 150,000 BTU input. 
    You took out a 225,000 BTU boiler and replaced it with that? Look on a bladder tank info sheet and it won't be big enough for a 225,000 BTU boiler. Somewhere, I thought I read that there were a lot of rooms in this building. With fin tube radiation on the walls with bypasses under the elements and run by something like a Danfoss Mechanical bypass valve operated by a thermostat on the wall with a capillary tube from the thermostat to the valve. It probably has 1" copper tube for the fin tube and the bypasses. It probably splits somewhere from 1 1/4" to 1". If this is so, the 011 circulator is probably what you need to feed this loop. The other circulator goes to the smaller loop. If I am correct, it sounds like an account I had for years that I learned a lot about hydronics. Except that there was a mechanical room to send heated water to different wings of the building plus a huge heat recovery/air handler. If it is at all like that, measure but estimate roughly how many feet of tube you have that you can easily locate. Use D/2(squared)X.0408X length in feet. It will give you a close amount of water in the system. The expansion tank must be able to handle it.
    Is there any possibility that it had a primary loop with the boiler running on ODR? If it did, then those room thermostats controlled the individual rooms while the whole loop had constant circulation.
    Believe this or not, as a troubleshooting method, if you have an old Extrol tank like a #39 or #60 (better), connect it into the system with a double hose connection and see what happens. I've done it more times than I can remember. A used but working washing machine connection is a plumber's best friend. Or at least this one.
    Its possible that all your problems are around a undersized bladder tank. There's too much water expansion for the size of the tank and the amount of water in the system.
    This post was edited by an admin on March 9, 2014 11:41 PM.
  • knotgrumpy knotgrumpy @ 4:25 PM
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    Where did you go?

    Badger - What is the status?  Get any more pictures of the primary pump/feed/tank area?
  • unclejohn unclejohn @ 5:23 PM
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    The way

    The extroll tank is piped on it's side like that that has to be a air trap if you are coming off the bottom of the air seperater like you said.
  • heatpro02920 heatpro02920 @ 8:38 AM
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    I just glanced through the thread

    OK, I seen this thread earlier but noticed the thread count and figured it was a resolved issue...

    I have installed a bunch of TT prestige boilers, and I actually have a 175 in my own home...

    OK- so we dont have any high pressure coils in the system? {no indirect water heater or other dual inlet exchangers}

    So the first thing I would do is fill the system with the correct pressure {say 15psi, I'm not sure on your needs}, then shut the pressure reducing valve down and run the system, to make sure there is not a faulty 911s...

    I also would change a few things about the piping, If you could give a little more info about your system we can come up with the best way to pipe it... Why such large pumps, them things arent going to be cheap to run? Do you need them for your radiation?

    I use a grundfos alpha {set for delta P} on my primary and bumble bees {set for delta T} on my zones... I know for some reason the TT manual says to use huge pumps on the primary but I have had better luck with the alpha, I use it on every TT I do....

    I also use a larger expansion tank on the 175's, in my house I have a 60 and it feeds 3 hydro coils...

    I hate to say it, but I think I would want to start over if I went to your home for this problem, I would pipe it Primary secondary but I would keep my primary loop nice and short I would come out of the boiler and the only thing in my primary loop would be the circulator, very simple...

    Just come out of the boiler pipe your left outlet into the circ, then out of the circ go into your close tees and back to the other side of the unit... Now you have your loop and the supply and return for your zones...

    Come off the supply and on the way to your zone circs install your air vent, put the water feed and exp tank in the bottom of the air vent...

    now out of the air vent go to you 2 circulators {do the math and size them correctly, use delta T circs if you can} now on the other side {your return} you come back from the zones and install your purge stations to complete the zone loops...

    Here are some pics of my personal boiler in my home, I have changed this a bunch of times, its one of the first prestige boilers I installed, and I also started with a monster pump, now it has a alpha for the primary... The expansion tank isnt installed in these pics but I use a 60.. The piping has stayed pretty much the same, except it finished now and the alpha circ is installed...

    As you can see I jammed it all together, and I didn't follow all the rules on closely spaced Tee's, I had a very very tight space to work with, now where that free space on the lower wall is, sits my recirc piping and mini tank, also 2 feet in front of this board is a 170K BTU coal furnace, 3 feet to the left is a hybrid water tank and my well filtration system, on the other side is my water to water geo system { Not complete yet, someday Ill finish it}. rite next to the prestige boiler is my ru98 water heater... Needless to say I ran out of room in my boiler room, and I have already tripled its size since we built the house, and I have another utility room about 30 feet away that holds all my electrical, central vac, 1st floor air handler, whole house audio system, alarm, camera system, ect... So 600 sq feet of utility room and I need more...

    My tees are close enough but my 90's coming out are too close to the tee's. Now the system works great and I have no negative effects, but I wouldnt do that at a customers house, this is my own home and I wont complain, but with a customer, the system can work fine, and some other contractor will come along and trash it because its not "by the book" ...

    But anyway take a look at them pics, since you only have to do the work and pay for materials it may be a good idea...
  • icesailor icesailor @ 9:42 AM
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    Hydraulic Separator:

    Have you ever used Hydraulic Separators?
    They are a beautiful thing and eliminate turbulence that you might have by misplaced circulators or closely spaced tee's.

    Consider them as an accessory of the boiler and part of the primary loop. Then, the secondary loop is just like connecting to a boiler, the "old way".
    If the above boiler had been installed with a Hydraulic Separator/Low Loss Header between the primary and secondary, I doubt that there would have been a problem.
    Here's something. I think it originally came from Califfi. I know I had it with a bunch of stuff I had from them. Look at the drawings and read the article. I think it is around Fig. 7,
    This post was edited by an admin on March 12, 2014 9:52 AM.
  • heatpro02920 heatpro02920 @ 10:33 AM
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    icesailer, very true..

    I love using hydraulic separators, but with my boiler I couldn't fit it and I did it with parts I had on the shelf for the most part, not a low budget project but I am cheap.. I agree the op's boiler would probably be fine with one, but they don't give them away, 2-1 1/4" tees is much less than what I pay for the taco 1 1/4" hydraulic separator {I think its just under $500] the vdx125 is the same price and probably a better product but never in stock where I shop, actually they are all kind of tough to get locally... Although it acts as a filter and air separator too which is a plus, just a hard sell when I have done 100s of ps systems with closely spaced tees that work great..
    This post was edited by an admin on March 12, 2014 11:41 AM.
  • icesailor icesailor @ 2:03 PM
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    Those things:

    I don't do anything anymore. When I was, and the wall hung boilers I did, I considered the Hydraulic Separator as part of the boiler. I mounted it on plywood with F&M rings and plates. I just considered it as part of the "dressing" on the boiler.
    I looked at a few problem jobs that would have worked well with separators. Anyone not knowing completely what they were doing, would have their butt saved with one.
    It's just another form of idiot proof closely spaced tees.
  • icesailor icesailor @ 5:28 PM
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    Don't have?

    They don't carry what you need?
    Isn't there a Plumbers' Supply Co store near you? Anything that you want and use, they'll carry it. Of have it brought to you from New Bedford from their main distribution center.
    If you want it, Jay or Kevin Jones will be sure that you have it.
    And Lennie DiPasquale is in RI every Monday.
    Whatever I needed for the last 40 years, they always made sure that I had it. No driving around because the store only had 8 of the items I wanted. So I had to go to two or more stores afterward to get what I needed. They are wearing out trucks going back and forth to their stores all over New England.
    Low employee turnover. They treat their employees right.
    If their happy in the store, they're happy to get the stock to you. Unless you are a guy that will drive 2 hours to Home Depot because the Watts 3/4" #340 relief valve is $.55 less than the local supply house, you'll like them. You don't sound like one of those.
    I use that as an example because I was once in the Grand Poo-Bah of Home Depot in MA in South Boston, open 24 hours a day and you must be multi-lingual to work there (English is a second or third language).
  • heatpro02920 heatpro02920 @ 6:17 PM
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    its tough out here...

    I deal with 3 supply houses, and they are good to me, we have been doing business for years, I stock, a ton of fittings and parts for myself. I buy most of my materials online, I just put an order in for $3200 of webstone parts... I actually have a taco 1" hyd separator at the shop, and I used to have 2 of the 1 1/4" caleffis, but I used them this season... Normally I am 2 weeks out for installs and there aren't many emergency high end mod con installs happening rite now, so I can order the parts and get them pretty fast...

    I really only buy my units and parts that I need rite away at the supply houses now, sheet metal, air handlers, tubing, boilers, furnaces. I buy local, But the fittings, valves, water feeds, controls, circs, ect I buy online and get shipped in... not just because its less money, but for the time it saves, I have everyone make a list when ever the order is going in, I order that night, its in my office 2 days later.
    Locally a 3/4" male adapter is $2.40, I pay 88 cents... the difference is less subtle on stuff like circs and controls but warranty's are just as easy, I still deal with one person and I keep my costs down... I give the local supply houses a lot of business and I only use 3 small houses {well one is re michels but the other 2 I know the owners of personally}, it has worked thus far, but for some reason hyd separators are not on the shelves every where...

    heres an example of something that happened today, I needed a 3" black tee, and 2 3" black 90s... My cost at the supply house was almost $100, I just checked to see what they would cost me shipped and it was $40 cheaper, I needed them today, so I bought them locally, but just an example, that is money I save my customers, or I can make myself extra, which ever way you look at it, its money that stays on my side of the table...
    This post was edited by an admin on March 12, 2014 6:20 PM.
  • bluey410 bluey410 @ 2:22 PM
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    pressure change

    What it seems like is happening is when your pumps xome on its dropping the return psi below your fill psi and adding water try piping your fill into the outlet of your pump
  • Badger896 Badger896 @ 6:55 PM
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    Expansion tank resolved!!!

    ok everyone, couple if things i installed a gauge beteew the fill valve and the system so i could see where the pressure was coming from. the expansion tank was definately too small and causing unneeded pressure climb but i also discovered that after closing the valve to the boiler when i came back the next day the pressure gauge i installed earlier was pegged, turns out the bypass ball valve was seeping water past it even though it was off!!! so i replaced the valve, installed a larger expansion tank and made sure my pressure relief valve was set at 12 psi (which was now easy with the gauge i installed earlier) now at full temp my pressure is around 14 - 15 psi... all the rooms heating and everyone including the maintenance guy is happy!!!!
    i want to say thanks for the advice and help everyone gave!
  • Gordy Gordy @ 7:10 PM
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    Bypass ball valve?

    You mean for the fill supply valve?

    And you mean pressure reducing valve set to 12 psi.

    Did you check x tank pressure isolated from the system?

    Glad problem is resolved.
    This post was edited by an admin on March 12, 2014 7:12 PM.
  • Badger896 Badger896 @ 7:42 AM
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    Pressure reducing valve

    Yes pressure reducing valve not relief valve. sorry bout that. oh and yes the x tank static pressure at 12psi also..
  • Harvey Ramer Harvey Ramer @ 9:10 PM
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    Pumping Away

    Once again, the science behind pumping away from the point of no pressure change (expansion tank) remains intact.
    This method of piping is rock solid.
    Time and again I hear theories of the pump dropping the pressure at the inlet of the expansion tank and fill valve. CAN'T HAPPEN! As long as you have a functioning expansion tank and PRV, it doesn't matter what size pump you have, IT STILL CAN'T HAPPEN! 

    Physics are what they are and they don't care what anyone thinks about it.

  • Ironman Ironman @ 9:58 PM
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    And the laws of physics will outweigh the theories of physics every time.
    Bob Boan

    You can choose to do what you want, but you cannot choose the consequences.
  • Badger896 Badger896 @ 9:59 PM
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    Bypass valve

    It was the valve that bypasses the press red valve circuit. it was always off but until i could isolate the fill piping from the boiler there was really no way for me to tell that a valve thst was OFF was leaking past it!!! GO FIGURE
  • Tom Tom @ 7:16 AM
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    Thanks for the answer

    For closing the thread and giving us the answer. It drives me crazy to read many, many posts and then no answer!!
  • SWEI SWEI @ 11:20 AM
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    Let us know

    how that 006 on the primary works out.
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