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contractor installed radiant floor in bathroom but it doesn't work

spinnyt Member Posts: 2
I just had a bathroom remodel done. I used to have a baseboard heater in there which my contractor said he could convert to hydronic radiant floor heating.
I believe all he did was put pex into the new cement under the floor tiles and just attached the pex to the feed and return pipes from the baseboard.
I don't feel the floor getting warm at all. It feel like the hot water stops right where the pex starts and the return [shown in picture] is cold.
I have a taco pump on the retrun side of my boiler only [shown in picture]
The two zones [basement and first floor] have no problems heating the house in the past.
Am i screwed or would something like an additional circulating pump on the pex return help the situation?
Thanks in advance!


  • STEVEusaPA
    STEVEusaPA Member Posts: 5,689
    Would need to see pics of the piping or maybe a drawing . Show a pic of where the supply/return of pex connect.
    But it sounds like it's just piped wrong. If he took the radiant loop off of the baseboard loop, you'll never get any flow. Just putting a circ on it wont help probably either, without a mixing valve or some other 'help' BTW, Dan has a nice diagram in one of his books (drawing a blank--I think it's "Pumping Away" but it could be Primary-Secondary) that shows a radiant zone taken off of a baseboard zone.
    How bout the obvious question...where's the contractor you paid?
  • rick in Alaska
    rick in Alaska Member Posts: 1,362
    If he tied the radiant loop in to the baseboard loop in series, it will flow just fine. Assuming there is no other baseboards on the loop.
    My guess is that the loop is air bound and needs to be purged. We would need to see pictures of the piping at the boiler and the baseboard though.
    Also, if he did just tie in to a regular baseboard loop with out any way of mixing the water temperature down, that floor is going to get hot enough you won't be able to walk on it.
  • rick in Alaska
    rick in Alaska Member Posts: 1,362
    Edit: Assuming there are no other baseboards on the loop.
    Sorry, had to fix that one and couldn't make the edit button work.
  • icesailor
    icesailor Member Posts: 7,265
    "Contractors" should stick to butchering wood and stringing along their subs for payments. And stop thinking they are hydronic experts when they can't properly kame a house air tight or water tight.

    If the baseboards are hot that come before the radiant loop and get cold going into the "radiant" loop, the restriction is so great in the floor that it is coming out of the floor cold. Like it does when you series loop a toe kick floor heater. It is hot until the heater, then it is cold.

    Mr. Expert Contractor installed that vent Tee with the coin vent to get the air out of that side of the loop. You don't need another photo to know that it isn't going to work.

    A good proper purging might get some more water flowing through the floor. Which will probably make the floor too hot to stand on.

    Is this "Contractor" on Angie's List and highly rated for installing radiant floors on bathrooms?

    If that radiant floor in in the first floor and that's why you can photograph it, you need to get a REAP heating professional in there to connect it like it once was (and worked) and have the radiant floor loop put on a separate floor zone with mixed hot water. So as not to burn your toesies.

    You CAN educate Stupidity.
    Only if they listen.
  • jonny88
    jonny88 Member Posts: 1,139
    Dan has a whole book on the do's and dont's.I gave a few of my books on loan to someone and thats the last I saw of them.If you have a radiant zone you require lower water temps.From what I can see you dont have a mixing valve installed for the bathroom zone.Most likely you run you system at a max of 180 which is way to hot for radiant.There is a diagram in Dans book on how to take a radiant loop of a baseboard zone.Guess what it works.From what I can see your zone is not piped correctly as Rick said its going to get to hot.Go of the wall and take a look at system piping,you might find a link there.Good luck to you.Whatever you have can always be fixed so dont get to worried.
  • Rich_49
    Rich_49 Member Posts: 2,692
    Besides the possible problems mentioned by others . Is this bathroom floor connected to an outside wall ? Did the contractor insulate the floor below the radiant ?
    Let's say it is connected with an outside wall in ALASKA . The room air is certainly warmer than the outside . If the radiant floor is connected to an outside wall you have a problem . Hot goes to cold and it also goes to the coldest . Thermal bridging is a **** and is too often overlooked because most geniuses believe heat rises . NOT! Some type of insulation must go between the exterior sheathing and the heated floor , especially in ALASKA . The joist space below the radiant floor must also be insulated .
    You didn't get what you didn't pay for and it will never be what you thought it would .
    Langans Plumbing & Heating LLC
    Serving most of New Jersey, Eastern Pa .
    Consultation, Design & Installation anywhere
    Rich McGrath 732-581-3833
  • icesailor
    icesailor Member Posts: 7,265

    "" I gave a few of my books on loan to someone and that's the last I saw of them. ""

    Never loan your valuable books to anyone. They never return them, and then throw them out. If you remember loaning it them to someone, they will deny that you did. Some are irreplaceable.
  • jonny88
    jonny88 Member Posts: 1,139
    To true Mr Ice.I got to restock.They have actually helped me out in real life situations,an investment that keeps on repaying.Waiting for you to put pen to paper.
  • RobG
    RobG Member Posts: 1,850
    icesailor said:


    "" I gave a few of my books on loan to someone and that's the last I saw of them. ""

    Never loan your valuable books to anyone. They never return them, and then throw them out. If you remember loaning it them to someone, they will deny that you did. Some are irreplaceable.

    Same goes for tools!
  • spinnyt
    spinnyt Member Posts: 2
    Thanks everyone for the swift replies.
    I wasn't able to babysit the contractor the day he installed the pex and poured the concrete [or whatever it was] over the tubing so not sure exactly what he did.
    I'll try to explain my system to the best of my knowledge and if need be I can take more photos. Sounds like I am actually lucky though that it doesn't work or i'd have burnt feet by now - there definitely isn't any sort of mixing valve that would bring colder water in anywhere.
    this radiant floor is installed in the middle of a loop with 5 other baseboards in different rooms. I don't think they are run in series - there is a supply ring that feeds all of them and a separate return ring.
    On the radiant supply line before the pex there is a limiter ball valve or something. Then it does two 90 degree turns and up into the floor [the reverse of the return photo in my original post - minus the bleeder valve]
    The room the floor is in does have an exterior wall but there is a bathtub in between the wall and the [supposed] heated floor so it isn't in direct contact with exterior wall.

    I'll try to get a hold of Dan's book.

    Thanks for all of the feedback!
  • Snowmelt
    Snowmelt Member Posts: 1,334
    You may want a seperate pump for the bathroom heat. With a mixing valve set on 120. If you feel the tube getting hot, hopefully you will feel the floor getting warm. If you feel the basement ceiling getting warm, you will have to install some insulation.
  • icesailor
    icesailor Member Posts: 7,265
    The "baseboard" heaters must be old. The photo shows 3/4" copper tube. Then, it is reduced with the PEX to 1/2" or less. Disconnect the PEX floor loop from the copper baseboard loops and tie the baseboards back together so they work like they were intended to. Then, treat the radiant bathroom floor as a separate item. You need a mixer for the bathroom floor and its own zone. You have to go back to a point before the first radiator or that radiator/baseboard will get hot when the floor is calling.

    Chances are good that the floor will work OK. As long as it is its own zone with its own thermostat.

    The opposite of what Mr. Contractor did would be to put a big cast iron radiator in that place. the first baseboards would get really hot, the radiator would take a long time getting hot, and the last baseboards wouldn't get hot until the whole radiator got hot.