Slab Radiant.. Is this plumbed correctly?

[Ccap]

They to figure out if this is plumbed correctly.

Because I am not getting any more than 0 to 1 gpm out of the circular pump.

The radiant pipes are 7/8" and I think in order to get my floor working correctly, I need to increase flow and get the warm water through the system faster.

Thoughts?

 

[Diehard]

Not really familiar with the different arrangements but i did come across this site that talks a bit about a similar system, I believe.
https://www.pmmag.com/articles/8803...y-thermostatic-valves-br-john-siegenthaler-pe


"The Magic Of Closely Spaced Tees
I also see a number of piping designs where the pressure drop created in other parts of the system under various operating modes interferes with the modulation of the three-way valves. This can be solved by connecting the three-way valve and the distribution system it serves to the boiler loop using a pair of closely spaced tees as shown in Figure 4.
With this primary/secondary interface, flow through the three-way thermostatic valve is driven solely by the pressure differentials created by the radiant distribution circulator. The operation of other circulators in the system will not interfere with these flow proportions. It's just another example of how coupling loops together using closely spaced tees (e.g., primary/secondary piping) helps keep the peace among several circulators. This piping is also appropriate when motorized three-way valves are piped into a system.

Use the piping techniques we've discussed to make the three-way valves you install work as you intended. They'll return the favor by providing years of accurate and trouble-free service."

 

[Ccap]

Thank you Very much for your reply. I am going to forward this to the plumber and make sure we correct the plumbing. With this new correction, will this also increase the water flow (GPM) through the manifold and into the radiant? With the tubing size and length of the radiant zones, what should the flow be?

Also the other zone is baseboard heat as an FYI.

Another question. Should the circ pump be wired as a call from the thermostat or should it be a switch and you leave it on regardless if the boiler is calling for heat or not. Right I have it it the thermostat is satisfied, the boiler and circ pump shut off. I am thinking the water should always be flowing.

In the 2 circ pump example. how should it be wired?

Thanks again.

 

[Diehard]

As I had said, I am not really familiar with the different arrangements. Just thought this info and web site may or may not help.
Who designed the system?
The flow rate I believe(just reading up on this stuff now) is typically on the low side. Based on many variables like size and length of piping, required BTU to be transferred, an optimum delta T of feed temp vs return temp., etc.
The designer/person that ran the numbers should have a handle on it.
To be honest with you, I can't even follow your piping to even try to figure it out.

 

[wood4d]

for starters i always put the circ pump after the thermostatic valve on push with radiant. if you have low flow on that you need a more gpm pump. i dont know what the circ pumps in this photo can do as far as gpm but you need more gpm than a taco 007 for radiant. Also if you want to fix YOUR plumbing you cant ask a vague question about length of radiant zones and tubing size. It looks to me like you have 1 3/4 pipe feeding 3 3/4 radiant zones. Does that sound good? dont bash the plumber on this because he knows a lot more than we do about your system and we are guessing about pipe sizing.. with no call for heat nothing should run ever otherwise you might as well wire the circ into a wall outlet. does this unit control 2 pumps?

 

[Ccap]

for starters i always put the circ pump after the thermostatic valve on push with radiant. if you have low flow on that you need a more gpm pump. i dont know what the circ pumps in this photo can do as far as gpm but you need more gpm than a taco 007 for radiant. Also if you want to fix YOUR plumbing you cant ask a vague question about length of radiant zones and tubing size. It looks to me like you have 1 3/4 pipe feeding 3 3/4 radiant zones. Does that sound good? dont bash the plumber on this because he knows a lot more than we do about your system and we are guessing about pipe sizing.. with no call for heat nothing should run ever otherwise you might as well wire the circ into a wall outlet. does this unit control 2 pumps?

 

[Ccap]

Believe me. I am not bashing the plumber. He himself is scratching his head on the best way to pipe it. Right now it's just a circ pump ahead of the mixing valve and it only displays 0 to 1 gpm.

You are correct. The 3/4 radiant zones then go into pex tubing with is 7/8". I am not familiar with the taco 007 and how they compare with what is installed.

Plus the boiler serves baseboard heat upstairs.