Im trying to figure out what circulator pump I need for my radiant floor. I have a 32'x41'x6" concrete floor in an older red iron building with the 12" insulated panels that lock together. The building has 10ft high walls with some Batt insulation and a tin roof. The pex is about 3" below the surface. There is 2" insulation under the concrete with a vapor barrier. There are 4 circuits of 1/2" nibco oxygen barrier pex two are at 150ft and two are at 360ft. I have a 105,000 btu propane crown cast iron boiler. I used the following website https://www.taco-hvac.com/uploads/FileLibrary/SelectingCirculators.pdf to try and figure out the pump size I need, but im having some trouble. I got 5.4 GPM with 32ft of head loss. So I was thinking about using the taco 009. Is this right or?
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Radaint Floor Ciculation Pump
- Thread starter bauer0667
- Start date
engineer2
Well-known member
I like Taco pumps. Very reliable. Mine are 13 years old and never had a problem. I would call them up or contact one of their sales offices. It's something you want to get right the first time.
As I said in another thread -- if your loops are equal? Yours are not.
... going over 300ft is a no no. You can't have a simple manifold -- the flow is not going to go through the 360 loops without some additional help.
My preferred pump is the Grundfos 15-42F .. under $100. It will be fine for the primary -- you are going to have to play around with the actual zone loops
-- you may need a bit more push w/ the 360's. Now I understand why the return is so cold in your system -- those 360's should be split -- you should have done 6 loops. The water is just too cold going through that length -- if you did constant circulation the slab would eventually heat up and the returned tempered a bit.
This is why getting some proper education will help ... maybe someone on one of the heating forums -- not the HVAC forums. You need to find someone who has encountered this.
... going over 300ft is a no no. You can't have a simple manifold -- the flow is not going to go through the 360 loops without some additional help.
My preferred pump is the Grundfos 15-42F .. under $100. It will be fine for the primary -- you are going to have to play around with the actual zone loops
-- you may need a bit more push w/ the 360's. Now I understand why the return is so cold in your system -- those 360's should be split -- you should have done 6 loops. The water is just too cold going through that length -- if you did constant circulation the slab would eventually heat up and the returned tempered a bit.
This is why getting some proper education will help ... maybe someone on one of the heating forums -- not the HVAC forums. You need to find someone who has encountered this.
engineer2
Well-known member
I did 2 parallel loops flowing in opposite directions for mine. It works great.
For a single loop that radiates evenly, you could use a parallel spiral.
For a single loop that radiates evenly, you could use a parallel spiral.
I did 2 parallel loops flowing in opposite directions for mine. It works great.
For a single loop that radiates evenly, you could use a parallel spiral.
That's how I did my three sided addition -- tile floor lots of glass. It looks like a nautilus. Wanted to make sure I had even heat and as quick change as possible
I’m not an in floor heat guy but I don’t understand why someone would install loops of different lengths. The limited installs I have done being a builder..... I don’t go over 250’ a loop and I make all loops as equal as possible.
That's my upper limit also -- it's better to add another loop and drop them all down. The tubing is the same and the cost of the larger manifold is almost nothing. Sometimes there is no way around having a short loop -- zoned bathroom. I'm doing my steps -- so that's going to be short.