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hydronic heated floor not warming...PLEASE HELP

Hey guys, it would be wonderful if you could help me out with the problem i am having with my infloor heating system....the house is only 2 years old and the previous owner claims that the heat in the living room was working fine before i bought is the problem:

one thermostat controls the heat for the entry hallway and living room....the hallway gets warm with no problems however that is not the case with the living room...i hired two different plumbers and they have both bled the entire system of any airbubbles...the second plumber made me replace the water pump to a stronger one with multispeed feature...the supply pipes get warm, the return pipes get sort of warm but the living room is always cold, the hallway gets room real fast as a matter of fact...please help, what could be going on? even the plumbers are stunned and dont know what to do....could there be problems underground...there is no sign of water on the floor signalling a cracked pipe or anything like that....please help thanks so much


  • GordyGordy Member Posts: 7,111
    edited April 2012
    some questions

    Is this a slab on grade with tubes poured in concrete?

    If not is it tubes under the floor? Or on top of the floor?

    Diameter of tubing used?

    How many loops supply the living room?

    How many Square feet is the living room?

    Location of the thermostat in reference to these two rooms? 

    Are the floor coverings different from the entry way, and living room?

    Is it possible the thermostat is located where it may be getting satisfied before the living room gets to set point? Example location being hall/entry way.

    What water temps are being supplied to the loops?

    These are all trouble shooting starting questions

  • Mark EathertonMark Eatherton Member Posts: 5,582

    Manifold locations and methods of flow control. You could have one thermostat, but a dozen operators on a manifold, and a few dead operators for those circuits.

    Got photographs?

    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • josh2012josh2012 Member Posts: 7
    pic attached

    hey guys, thank so much for your replies....i have attached a pic to show u the heater assembly....the living room is in the first floor with no basement i guess its just PEX tubes in concrete..not sure tho but it has to be the same set up as the entry, the thermostat is in the living room...both the entry and living room are covered with laminate flooring...note the replaced valve, water pump, supply and return pipes in the pic....what could be going on???
  • SlimpickinsSlimpickins Member Posts: 314

    I'm not sure of what's going on with your underground piping but the near boiler piping is a mess. From the fuzzy pic it looks like a bad attempt at primary/secondary piping. You need to get a real pro that is knowledgeable about correct near boiler piping and radiant design. You can go to the Find a Contractor tab at the top of the page. If nobody is local, let us know where you are and we can try to get you help. If you can get any info from the previous owner, contractor or builder about tubing layout, that would help who ever you find. I definitely wouldn't not use the original installer that did that botch job.

    Good luck and keep us in the loop.
  • GordyGordy Member Posts: 7,111
    more pics

    I think a few more pics at different views( behind, and sides of boiler). Pics of where actual supply, and return piping for the radiant loops are. See some linguini in there kind of hard to tell where it all goes.

    The boiler is in the basement?

    Are these rooms the only rooms heated with the boiler? OR are other rooms radiant besides the two in question?

    The thermostat is in the living room. Which is the room that is running cooler. Are you sure that there is nothing effecting the thermostats percieved reading of the temperature of the room per say sun shining on it, or a lamp that gets used often. Is it in the living room yet mounted close to the hall way where that temp may influence the tstats reading?

    Sounds like simple obvious questions, but sometimes everyone looks at the boiler room for the problem when it could be somewhere else. Trouble shooting should start from the problem room back to the boiler room with process of elimination.

  • SlimpickinsSlimpickins Member Posts: 314
    edited April 2012
    Following up

    It's pretty obvious that his boiler is incorrectly piped and pumped and sure, there may be problems beyond the mech room. If there isn't a problem with his boiler now, there will be without changes and that would include boiler protection.We could go on and on here with more pics, post's and everyone givng their .02 to further confuse the original poster. Josh needs someone on-site to do a complete evaluation and proceed from there as I said on my previous post. Not a knock on his plumbers he had out previously but he needs someone who is well versed in near boiler piping and radiant design. In my experience not a lot of plumbers or even HVAC techs and contractors have this knowledge. Fortunately its the end of the heating season and there's time to approach his problem sensibly. 
  • GordyGordy Member Posts: 7,111
    edited April 2012

    I hope you do not think I was implying nothing is wrong in the boiler room. You are correct of course.  Hence you covered that. But there is a habit of some so called heating professionals that bombard a problem with parts, and in the end the problem is not fixed, and the homeowner still gets the bill. There outta be a law.

    You know as well as I do some pretty horrific looking installs can still "work". Old homeowner claims it did, and new homeowner claims it does not. Maybe the level of working heat is not the same opinion of the original homeowner, as the new.

    At any rate some pics, and opinions here could at least help steer josh with his next encounter with a "heating pro" as to what to expect to be done to get things right.

  • josh2012josh2012 Member Posts: 7
    more pics

    thanks again for your replies the living room and the entry are not the only places which have radiant heat...there are four zones in total (hence 4 valves), once again the thermostat is in the living room...the hallway controlled by it gets warm but not the living it is a matter of making one step to the right to notice the temp difference in the hallway and living room.....more pics attached, thanks'
  • josh2012josh2012 Member Posts: 7
    more pix

    please help thanks
  • Mark EathertonMark Eatherton Member Posts: 5,582
    There must be a manifold someplace...

    And once you find it, you will be closer to resolving your issues... Look in closets, crawl spaces etc. The line coming from the zone valve is coming from that manifold, and you probably have an air bound circuit or two to contend with.

    You do have a lot of other "issues" that need to be resolved in the mechanical room as well that WILL come back to haunt you.

    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • josh2012josh2012 Member Posts: 7
    what other problems....

    Are u referring to exactly?
  • Jean-David BeyerJean-David Beyer Member Posts: 2,530
    I have a "missing manifold"

    In my house, the downstairs is heated by (mostly) 1/2 inch copper tubing inside a concrete slab at grade. A one-inch copper tube comes out of the slab into  the boiler (on the secondary side of the closely spaced Ts). On the other side of the closely spaced Ts is the zone circulator that drives that zone by splitting in a do-it-yourself manifold that is a bunch of 1x1x1/2 inch Ts, followed by 1/2 inch ball valves and enters the slab. So the supply manifold you can find. Now there are 5 circuits in the slab, but only the one-inch tube comes out, so inside the slab must be the return manifold. It must be a bunch of 1x1x1/2 inch Ts, or maybe some of those and some 3/4 x 3/4x1/2 inch ones. Did they make hydronic manifolds in 1950? But short of digging out a pit under the whole slab and putting an X-ray machine above and x-ray film underneath, I will never know for sure which ball valve controls which room (though I think I have figured that out with an IR thermometer, a lot of time, a lot of logic, and three tries, because I got it wrong the first two tries), and where the Ts are and what size tubes they all are. It is all a little over 60 years old and does not seem to leak. If it does leak, it does so so slowly that pressure does not go down (or up) if I shut off the ball valve in the makeup water system for a month or so. (My contractors hate when I do that, even though I look at the pressure every coupla days and it has a LWCO on it (two if you count the U- control that claims to satisfy the AHJ in some areas (but not here)).
  • Mark EathertonMark Eatherton Member Posts: 5,582
    Incorrect piping practices...

    From what I can "see", based on the pictures, the boiler is not piped in a primary/secondary configuration, which is critical to the proper operation of the "system". Incorrect piping results in the boiler short cycling, which leads to plugged up heat exchangers. Plugged up heat exchangers can lead to the spillage of the products of combustion, and that is NEVER a good scenario to be in.

    The methods and manners of piping indicate that they system was not installed by a professional. We don't typically use plastic around the near boiler piping. Usually it is copper or steel, and the plastic is limited to distribution lines, away from the boiler. None of the piping is properly supported. Code requires the plastic piping to be anchored every 24 to 30" or at every change in direction.

    It is extremely hard to judge this system without having a piping schematic, but it just doesn't look right to the trained eye.

    Was this system installed by a licensed professional, or a weekend DIY warrior?

    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Mark EathertonMark Eatherton Member Posts: 5,582
    Long running manifold...

    JD, It was common back in the day, to have a "long running manifold", which is probably under the cover of the slab. Individual branches drop off of the piping below the floor as it goes along the supply route. This can be problematic, as you well know, because each branch is an opportunity for leaks or stress failure points.

    It's not missing, its just spread clear across your floor, below grade.

    You could probably find it with a good IR imaging camera if you had to. See if your local fire department has one they might let you "borrow". Most all of them have them for finding hot spots in fires that have been recently extinguished. They are recycled from the war effort.

    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Jean-David BeyerJean-David Beyer Member Posts: 2,530
    Maybe the stress is less now.

    I know the "mainfold" is really there, buried in the concrete. Originally, it had a boiler with no reset, so it turned on at about 140F when the thermostat was unsatisfied, and off when it was satisfied. So lots of expansion and contraction. I did not see or hear it, because the tubing was not really free to move in all that concrete. But the stresses must have been there. And it cycled 30 times an hour or thereabouts because it was bouncing off the upper limit on the operating hydrostat. (Not the safety limit one.)

     Now I have a tightly controlled outdoor reset, so it turns on and just runs for many hours at a time, and at lower temperatures (between 75F and 120F depending on outdoor temperature).

    Luckily, I have not needed to find any leaks. I hope I never have to. If it runs another 27 years, I will not know about it until I am dead; assuming I die before I get to 100. But if it quits with a bad leak before that, I guess I will put radiant into the ceiling. Like with the thin WarmBoard or something like that.
  • josh2012josh2012 Member Posts: 7
    thanks david

    for going off-topic and discussing ur own problem...any feedback from others will be appreciated.
  • RobGRobG Member Posts: 1,850
    Floor not warming

    As stated before, your system was not installed by a competent professional and needs to be re-piped at the mechanical room. I know that it's not the answer you wanted to hear but in the long run it will save you a ton of money on fuel and increase your comfort significantly. That's the bad news. The good news is that it appears as though you have most if not all the components for the project. If you tell us where you are located we may be able to guide to the right person / company to help you.

  • Tim P.Tim P. Member Posts: 50
    then again..

    It could be that all of the piping is right there.

    Looking at the original photo and the subsequent close-up shots, I have to wonder if we are looking at all the manifold there is.

    I imagine the hallway as a small area with it's own loop, and the living room as a large area with another loop.  The two are joined in the boiler room with a tee.

    Small loop = warm, Long loop = cold.  With no way to balance and an assumed longer living room loop, you could get this issue.

    If you are able to close the valve on the return from hallway, I would be curious to see if the living room gets warmer.
  • josh2012josh2012 Member Posts: 7
    work that plumbers have done.....

    1) flushed air out of system using pressure after PRV domestic

    2) added and replaced auto air vents

    3) re piped zone to reverse return header

    4) removed balancing shut offs to see if they were defective (ok)

    5) added hose bib for future flushing

    6) replaced circ pump

    ** it is confirmed that there is no flow through 2 out of the 3 zones

    *** something possibly stuck in the lines

    please any possible solutions guys????
  • ZmanZman Member Posts: 3,476

    It would be helpful if you could draw your existing piping. It is hard to tell from the pics if the boiler piping in terminally incorrect or just ugly. I suspect you have some huge air bubbles in your zones that your circulators can't move. Strategically located purge valves may remedy this. 
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • SlimpickinsSlimpickins Member Posts: 314
    Possible solution is

    get someone that knows something to look at your system. Just adding and replacing auto vents isn't going to help, you already have an air scoop which is sufficient. The people here that have given you advice, which is to get a true profession, could figure out your problem within an hour or two. Not to diss the plumbers you've had out but they've obviously don't have the training and experience. I have a feeling that your tubing to the trouble zones are not hooked up correctly at the manifolds.

    Even if we can help you diagnosis the problem here, you're still going to need a competent professional to perform the work. I'll say it again, click the "Find A Contractor" Tab at the top of this page or tell us where you are and we can try to set you up with a pro. Hope I'm not coming off too harsh, keep us informed.
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