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[Sprinter]

Keep in mind with that drawing there is now way to control supply temp to each zone.  Each zone further down stream from the boiler supply will see lower temps. Think moose antlers or why they use that type

[american-pacemaker]

I have been second guessing myself since I designed this system. I am not sure how much the temp drop will be over the primary on this setup.

[LittleJohn]

Only way to truely control the temperature on secondaries (or zones) would be to have a mixing valve... this is assuming you want/need the secondaries to be cooler than your main

In my application my main runs about 180F (approximate temp of OWB, after going thru HX), secondaries runs at either 110F for slab or 150F underfloor

[slimjim]

I think what Sprinter is saying is that the downstream zone temps will drop as more zones come on, this is why they should be set up in priority, lowest demand at the end of the loop and temp gauges on supply and return to monitor the differential, adjust circ speed to heat full heat load with about a 20 degree differential.

[american-pacemaker]

Slimjim, will the speed of the circulator mess up the amount of btu's going to each secondary ? I have really thought about going to
the moose antler design ?

[slimjim]

No it will be fine on your system Larry!

[Sprinter]

A simple adjustment to the pipe layout will solve the issue. Just make sure the first thing the boiler supply sees is the feed or supply to each zone, then the returns. Cuz who cares what temps are downstream of the last supply.
The other option is moose antler headers. There are other ways. A good read on what P&S piping really is and what all the different versions are will answer all ?

[aries9245]

I have a question for you guys i about to do some retrofitting on my primary and secondary system with 6 zone baseboard and 4 zone radiant heat  as of now @ of my radiant loops have a circulator but baseboard only has 1 to feed all what would be the best way to pipe into a primary  secondary system  and would I have use a separate pump for each zone for my baseboard also or can I use a wilo eco pump? Or similar

[LittleJohn]

I have a question for you guys i about to do some retrofitting on my primary and secondary system with 6 zone baseboard and 4 zone radiant heat  as of now @ of my radiant loops have a circulator but baseboard only has 1 to feed all what would be the best way to pipe into a primary  secondary system  and would I have use a separate pump for each zone for my baseboard also or can I use a wilo eco pump? Or similar

You have to have an actuatoror or pump on each zone.

I prefer zone valves, as there is less chance of ghost flows potentially occuring, but it really is what ever you are comfortable with installing.  LIKE I SAID THIS IS MY OPINION, it might not be 100% right, but it works for me 

[aries9245]

Little John the way I did it was I ran my primary and secondary loops a 007 on primary loop with t on supply with 007 pump to supply baseboard zones with zone valves second t on return for aseboard into primary loop then it goes directly to my radiant loops all with there own circ pump and finally a 008 pump on return before my HX and it working fantastic all zones are feed without any starvation so I think I solved my problem..

[Sloppy_Snood]

Primary / secondary physics says minimum 8x pipe diameter on supply side and 4x pipe diameter on return of each set of tee's which is really cramping me for the space I have.

Where does that requirement come from in physics?   

The only "requirement" on a manifold I ever read about was no more that 4 times the main manifold pipe diameter between the supply and return reducing tees.  Every copper manifold I saw at the big box stores WAY less than 8X manifold pipe diameter on the supply side.

Just trying to understand before I start soldering my manifold together.

[LittleJohn]

I am not 100% certain, but I know that you must have a minimum length of pipe between one set of closely spaced tee and the next, so that the water has a chance to remix.  Otherwise there is a chance you could be pulling from the previous set of closely spaced tees not the main loop and cause some gremlins in the system.

[american-pacemaker]

Sloppy sorry I didn't see your post. The physics is from a flow standpoint and what happens when the dimensions are not right. Go to
the web site comfort-calc.net this is one of the best websites for this part of the primary secondary design. I just got my system running for both the inside oil boiler and the outside wood boiler and both are working extremely well.

[american-pacemaker]

I tried to upload a picture but the upload folder is full