primary/secondary

bigugh_4

book on primary/secondary pumping. Determine the correct heat loss of the building. Determine the correct loads of the zones. dteremine the correct temps of those loads. A rad. floor system needs cooler water that the convector, or BB will. Now plug in the correct numbers and walla On paper it will work! Installation is the next thing. Good luck

bottomheater_2

I'm doing my first primary/secondary on a itty bitty system with a small convector load, a smaller radiant load, and a smaller still baseboard load. Any harm done in oringinating each zone at individual closely space tee sets? Also, if a taco 007 is driving my 1-1/4 primary, can i use the same pump in the secondary loops and rely on the smaller pipe sizes to throttle the flow rate, or must i find smaller pumps? god bless y'all and this wonderful wall.

bottomheater_2

thanks bigugh but its thelayout

my math is in place, its just the tee takeoff pattern i was wondering about. my only experience with p/s is in huge systems with 2-1/2 circling the building with the secondary loops dropping off the main with no common manifold. i did the same in miniature(75KBtu)

bigugh_4

layout?

A short common manifold, Properly sized is what I see you asking for, and how to TEE it? I'd take the hottest needed temp off first, i.e. the DHW. then the convectors and BB's, The Radiant floor would be last off the manifold, near the return to the boiler. TEES close together, allowing space.for valves & pumps working & service..Always think of air and how and where it will be or go.,and how to get it out! If you intend to insulate the manifold, space may be needed for that!

Dave_13

Here's one...

I understand the princible of where to pick off of the primary. The radiant loop is last because thats the low temp loop. What if the radiant loop is the only one calling for heat? It will be supplied the full primary temp. What do you do when you pipe in this fashion to protect that loop? Mixing valve?

Guy_5

Circulators

Pay close attention to the manufacturer's recommendations for circulator sizing on the primary loop. There is more going on there than just moving the water to the heat medium. In the low mass boilers FLOW is critical through the heat exchanger. Failure to maintain that flow will cause short cycling, flashing, or a host of other issues.
Please check the manual for the MFG specs. It will save you some headaches later.