Circulator layout

Ben_17

I must thank you for taking the time to help me.

If I have missed any details that you require let me know.

I hope it all makes sense!



T= air thermostat

V= Belimo B318B 3 way ccv 3/4" 7.4cv

P1=Taco 005

P2=Taco 008

P3=Taco 010

P4=Taco 005



All pipe is 1" unless noted

Combi tank connections are 3/4"

V1 is a outdoor compensated valve controlled by Resol M controller



T1 run P1

T2 run P2

T3 run P3

T2 or T3 calls for heat and S2 greater than S3 run P4

S2 greater than 170' run P3 and P4



Is this the best possible layout and pipe size?

STEVEusaPA

Is this your complete design?

Would it be safe to assume you have your heat loss completed and the radiant zones are designed for the btu and flow rate?

Things I would consider/change.

1.  If you like this design, I think you need a  circulator on the primary loop, probably a 007.  Also, depending on btu requirements, I think your primary loop should be 1 1/4.  Id put the circ next to, and pumping away from your compression tank.  I'd also move the P1 circ to the other side of the compression tank.

2.  A better design would be to skip the 3 way/bypass, and go with a 4 way with odr.  Put a circ, and the expansion tank on the boiler loop with the solar, and the high/low loops on the secondary, separated by the 4 way.  Then all your secondary loops could use smaller circs.  And the solar would add its btu's to the boiler loop where it would be available to the boiler, and all the heating loops.

3. "S2 greater then 170 run P3 & P4"?  Doesnt make sense to me.  I think when P4 runs, without a circ on the primary loop, it doesnt get the btus into the mix, so to speak. 

It's a little harder to determine pipe sizes without knowing the btu requirements for each zone.

Ben_17

"S2 greater then 170 run P3 & P4"?

"S2 greater then 170 run P3 & P4"? Doesnt make sense to me. I think when P4 runs, without a circ on the primary loop, it doesnt get the btus into the mix, so to speak.



P3 basement circ + P4 solar loop.I was going to use it to dump a pile of BTU's  in to the basement floor. But I will hold the mix temp @ 67' to prevent overheating. That circut shold work.

Correct me if I am wrong.

STEVEusaPA

I can't get it to work......

In my brain. If P3 &P4 are running, how are the buts getting from the solar tank/loop, into the basement loop? You need another circ, in my opinion. Maybe I'm wrong

CMadatMe

Won't Work

Need a system (loop) pump for starters. The other concern is the mix vlv placement for those radiant loops. If the radiant is calling those baseboard zones are going to starve. Don't see the reasoning behind the other mix vlv. I also don't understand the solar tank. Single coil?

Ben_17

Chris and Steve

This is why I enjoy these forums. Other peoples opinions are invaluable!

My current set-up is close to this layout and kinda works.... My system now does not have the solar tie or the bypass but works.... kinda.

Chris you are right, I have a starvation problem but with the 2 main radiant loops not the baseboards. My current system relies on the loop return water to "push" thorough the heat exchanger on my combi tank. My thought is to bypass the tank with V2 if I don't need the extra btu's. If V2 is bypassed (closed to P1) the return water from P1 will push around the coil and out to the baseboards correct?

Steve, As for the whole P3/4 thing..... My thinking is.... The water will push through the floor- return to the loop and pass through the solar store- around the bypass and back to the mix valve. What are you thinking?

How would you guys draw it out? If you see a problem can you offer a solution?

p.s. the solar store tanks are dual coil but as we are only dealing with the top (radiant supply) coil I figured drawing the bottom coil was not required



I appreciate your views and help,

Ben

CMadatMe

Post

A diagram exactly of how you have it set up now. Get the 3-way off the system loop. This reading may help you out.



http://www.caleffi.us/en_US/caleffi/Details/Magazines/pdf/idronics_7_us.pdf

Ben_17

current setup

This is how the installer did my system. I forgot to draw in the exp tank but he had no air removal.



This is not a boiler ---- like figure 6-9 in the pdf

CMadatMe

Mixing Valve

Is in the wrong place. If this was a 4-way mixing valve you'd be ok.

Ben_17

mix valve

Can you explain why and where it should be please.



http://www.caleffi.us/en_US/caleffi/Details/Magazines/pdf/idronics_7_us.pdf

Pg 37 shows no pump in the "primary" loop and the mix valve layed out the same as mine.

NRT_Rob

I see what you are trying to do

but you can do it more simply with no real downside.



I would replace P4 with a 3 way switching valve. drop S4 and V2. all flow diverts through solar coil if S3 is colder than S2. Saves pump energy and should give more effective solar heat extraction (lower flow, higher temperature extraction)



then move the whole solar tank sub assembly back into the V1-Radiant return circuit, so the solar heat water is present at V1's B port. then V1 should then only draw from A (combi coil) as necessary.



I'd probably move the expansion tank to the V1-radiant circuit approx where S1 is shown too. just in case.



so your "primary loop" is just the baseboard. Everything else is offloaded on to the radiant circuits, and V1 just pulls from the tank what is necessary to maintain circuit temp if the solar return reheat isn't enough to meet temp.

Ben_17

I agree Rob!

Good thing I don't like to spend time with the wife!!!

I spent the whole weekend cutting out everything that was there and plumbed it up as shown in the pic. Resol M is controlling the outdoor compensated circuit. 2 small PLC controllers handling other function and switching between 220v signals to 110v and 24v.

This weekend I am going to move my divert valve (V2) to the solar loop and remove the pump.

Rob, here is my question though...... If I move the solar to the radiant return line there is the possibility that the tank could supply water HOTTER then what I want in the floor in the late spring. Your thoughts?

NRT_Rob

good question

depends on how big of an issue you think that's going to be with your level of solar collection.



typically space heat will drop your tank temp pretty fast so if you "break spec" there it's unlikely to be for long, especially if you're dumping to a slab.



but if your array is really powerful, that may be less true and I may be all wet on saving you the second valve.