Closely Spaced Tees - maybe not?

amherstNH

Is my primary/secondary transition piping done right? From what I've researched, the closely spaced tees between p/s loops are not correct.

Just installed a Burnham Alpine 105 to replace oil unit. Noticed high volume of short cycling. Also had problem getting/maintaining heat on colder days (0 - 20 degrees). Contractor had USBoiler rep check it out and he changed some of the modulation parameters (now starts at lower mod and works up vs. starting at highest). That helped solve the short cycling but I still have problem with reaching demand heat. I asked the rep if he thought that piping might be wrong and he said that he wasn't the "piping police" - figured he didn't want to throw his customer under the bus. Contractor is a good guy and would change it if necessary but has no clue if it would make a difference - kinda just shrugged his shoulder. I'm think it needs fixing.

mastercraft

don't think so

The 'closely spaced tees should be no more than 3 times the pipe size used.   It looks like 1 1/4 IPS so your tees should be no more than 4"  between them.

Zman

Not

The closely spaced tee's  could not be more incorrect. See the attached drawing with credit to Mark Eatherton.

 You also should not mount circulators as the one in the picture. It will not last very long in that position.

Carl

Harvey Ramer

Couple of

things.



First the closely spaced tees are improperly configured. Imagine a straight piece of pipe with the 2 tees in it. If the straight piece is the boiler loop, the secondary side of the system should come off of the branches of those tees. Or it can be reversed with the straight piece of pipe on the secondary side and the boiler loop connected to the branches of the tees.



Another thing. Which direction is the boiler circulator pumping? Toward the tees or away from them?



Also make sure the boiler circulator is actually operating. There is a good chance it is locked up. You see, that circulator is water lubricated. With it mounted in that upright position you can get an air bubble within the motor housing. If this happens the bearings won't get lubricated and will seize up.



Try and get some pics from a little further back so we can see the whole system.



Harvey

Unknown

i concur

Everything what Harvey said

Unknown

i concur

Everything what Harvey said

Unknown

i concur

Everything what Harvey said

icesailor

Closely spaced tee's:

I have never seen a drawing of "Closely Spaced Tee's" for a primary/secondary piping system where ANY of the tees use the run it a tee to feed into the secondary piping. I've seen lots of piping schemes where one of both tees do it. That one uses two.

In order for it to be "primary/Secondary", it HAS to have circular flow through the closely spaced tees and the ells need to be far enough from the corner to maintain laminar flow. The Secondary has to maintain circular flow through the closely spaced tees so you get MIXING of the two different flowing fluids. They must be close together to maintain their connections with each other. The farther away the secondary closely spaced tees become, the less the connection between the secondary supply and return. Its critical mass. Too close and the turbulence of the secondary will interfere with the primary flow. Too far apart and the connection is lost. If you do it that way, you need to put a ball valve in the crossover pipe, shut it off, and then, the whole thing becomes a primary with the first pump (shown) as a booster pump for the rest of the system.



Here's how it happens in plumbing pipes. The same effect happens in pipes. You just can't see it.

http://img.tfd.com/architecture/f0524-01.png

Please tell us that there are circulators to the right after the air eliminator and not zone valves.

Steve Whitbeck

piping

It isn't piped properly BUT I don't have a real problem with it. the ruturn piping should have gone straight to the supply main with two tee's spaced about 1/2 inch apart. The boiler then connects to those tee's. Is there a pump to the right of that picture? OR are there multiple pumps off to the right?

M Lane

Deleted

Changed my mind

Zman

I'd...

Have to disagree with you on this one Steve.

It is just not close.The loops will ghost flow each other.

Carl

Rich_49

Piped

this way I do believe this circ was not even necessary .  Any other circs installed on this system are working in conjunction with this one pictured . Hell , if I was water I would never decide to make a right turn when I could continue forward with  no effort . This is more of a bypass than P/S if you could even entertain the thought of calling this P/S , the worst thing about this is 2 additional fittings (90's) were used to do it wrong . Have the installer remove the 2 90s and place the Tees where the 90s are now and call it a day . Sorry , maybe that's just because I'm lazy and stupid .

      Is there something in the water in New England that continues to make installers purchase , install and commission Burnham Alpine boilers poorly ? There has to be over 600 posts about this boiler from this specific area within the last 45 days .  I would venture a guess that US Boiler may want to do some extensive training in this part of the world or just stop shipping there .  We should start a movement to require hydraulic seperators or buffer tanks for P/S systems . Would be pretty hard to screw that up . Decoupling , air elimination and dirt separation all in one , Gee that sucks .  Hey guys , this one look familiar ?



And the fix for that one is really special

   Amherst , Don't let this happen to you . Have him remove the 90s and put the tees where they are .Don't allow yourself to become the subject a a 500 post discussion .

Harvey Ramer

Indeed!

That pic has burned a hole in all our collective heads.



I too have been noticing a lot of Alpine stuff and Navien problems. Ironic isn't it, the promoters of Navien only show up when someone is looking to make a purchase.



Harvey Ramer

Ironman

Details of Closely Spaced Tees

Here's a little less detailed drawing of just the Tees. Study it until it's clear, then go to Mark's drawing which includes more components.

Pughie1

Black Pipe

Not to kill that former post that Rich referred to but, Rich's pictured showed it so clear. Just curious how you guys feel about Black Pipe being used in the make up water line. We have always used brass.

                                                         John Pughe

knotgrumpy

Rich for President!

Exactly what I was thinking.  It would be nice to see one of these boilers set up correctly.  If I see Alpine in a thread I expect to see a piping fiasco.



I'd assume these are good boilers, but Burnham is taking it on the chin with their installers lack of knowledge.

Rich_49

Black on make up

Don't think much about it on that side of BFP .

Harvey Ramer

I don't much

like the idea of using black pipe with a giannoni heat exchanger in the mix. If it has to be used the water should be treated with inhibitor.



That's how I feel about it.



Harvey