Boiler Zoning Help!

jetrcr

First, I'm not a heating and cooling guy so forgive me if I ask obvious questions. Everything I have learned about heating is off the internet. I installed a high efficiency boiler in my parents home where they once had a traditional boiler system. The boiler I purchased stated that I should make a primary/secondary system so I bought Dan Holohan's book and set out to change the Direct connection piping into a three zone primary/secondary system. I fired up the system yesterday and the primary system seems to heat up just fine but only the first zone seems to work. All the circulators work but the remaining two zones stay cold. As I get that this is all very complicated so I put together a short attachment of how I set the system up. Is there something obvious that I'm missing here? Any help would be greatly appreciated!

Leon82

There can still be a sizable air pocked preventing flow. Did you power purge it? Purging at a higher psi can make it easier

jetrcr

No I didn't do that (actually I guess I'll have to learn what that is!) That's kind of what I was thinking but I wanted to make sure I didn't do anything dramatically wrong.
Thanks!

Leon82

On the pressure valve, some have a fast fill lever. Or you can use a hose with 2 female ends. Just keep an eye on the guage

You want the water to flow out without air sputtering

jetrcr

I made a hose with to female ends when I hydrostatically tested the boiler per the instructions. I'll try that tomorrow.
Thanks again!

ch4man

it'll never work. you need one more circulator on the 1-1/4 loop.
there is nothing to move the water past the zones closely spaced tees.

or eliminate the 1-1/4" loop altogether and tie the zone loops into the boiler loop that does have the one pump

ch4man

or..... where the boiler loop ties into the 1.25 loop, install a ball valve where the common pipe is and close it. this will induce flow where you need it

jetrcr

So I have one primary circulator and you think I need two?

Leon82

Wouldn't the zone circs do that?

Ironman

Brace yourself: some more bad news. You've piped it p/s series. Which means each secondary loop will be cooler than the previous one because it's receiving return water from that one. It should be piped p/s PARALLEL. The boiler circ should also be pumping toward the boiler on its return line.

ch4man

water is stupid and lazy. it take the path of least resistance. look at the zone loops again. those circs are just going to feed right back into themselves. they cannot induce a flow in the 1.25" loop. thats the purpose of hydrolic separation, to keep one loop from causing flow in another

Leon82

Oh, I didn't see the top picture at first

ch4man

can you post pix of the actual near boiler piping? take the photo from enough of a distance so we can see it all as well as closer shots.

HVACNUT

You don't need an additional primary circ. Just move it to the return.
The system should have been piped like the last diagram as @Ironman said.
The piping in the first diagram is for decreased zone temps as it goes down the line. You want 170 on all so parallel piping is needed.

ch4man

hvacnut is right, i shouldnt type before thinking. you need less, not more.
i beleive what ironman posted is what is sometimes called "moose antler piping"

jetrcr

I really appreciate all the feedback! So why does the directions show the primary pump on the outlet with an option to place it on the return if the correct way is to have it on the return?

Ironman

It should "pump away" from the Point Of No Pressure Change which is where the expansion tank connects. The loop that the expansion tank is in is considered the "primary loop". All secondary loops "see" the primary loop as the PONPC.

It's simply better for the boiler and the pump. But this is a minor issue compared to how you loop is piped wrong.

IDK what directions your referring to since IDK what boiler you have, but when the boiler is piped direct, then the circ should be on the supply after the PONPC. You may be confusing the diagram from another piping method.

jetrcr

Thanks. I think I understand what you are saying regarding pumping away from PONPC but since it's a loop it was not totally intuitive initially since the zone circulator pumps are pumping away, but after reading your post it makes sense to me now. Based on the layout I have now (attached) it would be very easy to change to this but not nearly as easy to move the primary to the return location. It sounds like this should still work but is not the optimal positioning, correct?

STEVEusaPA

Close. Move the circ on the boiler loop to the return, pumping into the boiler

newagedawn

STEVEusaPA said:

Close. Move the circ on the boiler loop to the return, pumping into the boiler

i agree