Splitting 1 hydronic zone into 2 using same plumbing? Sting?

The odd thing is, before I did the prime/sec loop, this same system pump supplied the same zone and satisfied it with a 100k oil boiler...
Why? My assumption is, that with the new set up, and the supply lines now getting fed by a 'tee' and a pump on the primary loop, probably 50% or less head is now available to the system pump/heat zones...and for this one troubled zone, it probably was just enough to push it past the tipping point.

So I am begining to conclude that I need a substantially larger system pump. I just measured all the footage of copper pipe, and counted up all the 90's and 45's on that zone, and measured the elements. I was astounded.. ( I did not install this zone!.. )
I came up with the following: Total length of 3/4 inch copper pipe: 284 ft, of which sits (first in line) 11 ft of HO element, and then another 34 ft of regular element..the return pipes loop back over the elements..
Number of 90's: 40
Number of 45's: 13

A whole lot of info in the previous posts. I am certainly confused as to what you have, what you tried and what you want.

It appears the first thing we need is a schematic of what you got. Boiler pumps, primary pump, system pump all on a 1" header - a lot of pumps for that small pipe. But zone valves? Yes, it is easy to overwhelm a 007 with too many zone valves. That is why I favor pumped zones over zone valves. Especially when forced into larger pumps. Pumps are about as cheap as zone valves and then then loops are easier to balance or if done right - don't need balancing.

The one zone you mention with 284 feet - does it go over to the neighbors house first? Certainly excessive.

The LL110 boiler is a sports car with a v-8 burner. Low mass with high input. It will swing with load and response. Proper boiler pump control is a must for this boiler. Even with my K-6 and it's 50 gallons of mass, it will bottom out on load and rely on the aquastat to shut off the boiler pump until the burner catches up.

Sting is simply trying to teach you the ZEN of hydronics, Grasshopper. If you come for advise, you must also listen to wisdom. Controls and design must be married properly. One good control layout may not apply to another good piping layout.

Hi Steam up..Thanks for jumping in on the topic..and thanks for making available your heat loss spread sheet...I used it.

steamup wrote:A whole lot of info in the previous posts. I am certainly confused as to what you have, what you tried and what you want.

-Well..As you say..there is a lot of info there..I thought I described what I have and what I tried...I have the two boilers.. 1 the LL110 coal/oil, 1 a 125mbtu wood boiler that I had in place. Prior to getting the LL110, I had in its place a low mass oil boiler which I ditched when I re-vamped the set up for the two boilers....The original set up was not primary/secondary..( I didn't install it), and thru educating myself found that a lot pertaining to the pipeing was messed up.

-What was there and is still in place is 3/4" suppy/return manifolds..4 zone set up. Yes, the zones have HW zone valves..some had problems of diff. nature, I corrected as needed.

-2 of the zones feed heating loads that utilize a fan coil unit, 1 is 4 ton, the other is 2.5 or 3 ton
- 1 zone is an indirect 40 gal hw tank.
- 1 zone is the baseboard heat zone.

PUMPS:
4 taco 007's
each boiler has 1 that feeds the primary loop...the primary loop itself has one, and there is one that feeds the supply manifold from the primary loop.

steamup wrote:The one zone you mention with 284 feet - does it go over to the neighbors house first? Certainly excessive.

-yes! excessive..I was shocked when I did an analysis of it..I didn't install it...but it is there...and is what it is

steamup wrote:The LL110 boiler is a sports car with a v-8 burner. Low mass with high input. It will swing with load and response. Proper boiler pump control is a must for this boiler. Even with my K-6 and it's 50 gallons of mass, it will bottom out on load and rely on the aquastat to shut off the boiler pump until the burner catches up.

-yes..I agree..and that is what is happening...and from my understaning and research, the big DeltaT numbers I have are a big part of the problem...

steamup wrote:Sting is simply trying to teach you the ZEN of hydronics, Grasshopper. If you come for advise, you must also listen to wisdom. Controls and design must be married properly. One good control layout may not apply to another good piping layout.

-Yes!..I agree!..Have read the books Sting advised..educated myself, and continue to do so..trying to learn more from the good folks here..I can only do that by asking questions and hopeing to get answers..
I am not trying to get off easy and find some miracle answer..I want to learn and understand... and do things the right way!..no doubt about that!.

..There ARE some things that just arn't feasable, economically or other..so I am trying to do the best with what I have. For instance, all the heating circuits are 3/4" copper...I can't rip all that out and replace it with a larger size.

-Zone valves-I would love to have pumps for the zones..but I just rebuilt what I have and replaced the zone valve controller, which is a Taco ZVC406exp....

Sooo...from what I can determine, my issue(s) come down to head/flow.
-The big DeltaT numbers on the Hydroair units (about 50*) overwhelm the boiler and cause the above problems that you stated..but at least the zones make temp set point.

-The excessive pipe resistance on the baseboard zone results in a DeltaT of like 85* and renders the zone inadequate..

So I was thinking from what I have learned and researched, that if I used a larger pump to feed the zones, I could achieve a greater GPM, which would improve my return water temps, make the problem zone at least more effective, and alleviate the issue of overwhelming the coal boiler..

Feel free to jump in with any conclusions/suggestions/corrections you may have!..Thats what I am here seeking!
Thanks..





TY

Holy Crap!!!

I'm a rookie, so I'll be little help.

Just curious if that wood boiler is in series along with all the other described piping?

This looks to have an interesting outcome!

Hi McG...

The set up is such that the boilers can be run in Series, Parallel, or stand alone..

Follow the advice of Steamup - its always more clear than my drivel

but yoru comment below was nagging me so I hunted it back up

stoker_RI wrote:-Anyway...as I think out loud to myself in my head...we rarely get down to the design* day temp.....prolly 95% of the time the pump would suffice with out a hitch, and I could use your ball squeezing trick, ball valve that is..to balance the load and make all the other zones nice nice with much tighter delta T's...

Now when ever you can simply adjust something that is no cost to do -- you should do it first. You can always be a professional and just throw money at a problem.

and if the system will heat nicely 95% of the time and that one zone falls behind only a few days out of the whole season -- You couldn't have a cheaper system to run. buy a resistance space heater for those few days to trim up the temp of a local space -- if necessary.

Pm sent with high tech rambling in response to Pm received. Solve the zone issues first, then look at boiler issues. All is not lost, most can be saved, some compromises will have to be made.

Yes Sting...I have come to that conclusion...not quite free...I'd be buying a bigger system pump..but total outlay of $$ will surely be less than any other option...and labor wise it is the easiest...and maybe, just maybe I'll see the $$ back in improved efficiency..

IT DEPENDS!

..but it will be nice to conclude this and see how the experiment affects the dynamics of things!

...and then I will join u for a (cyber) beer...
that is, if u partake in the suds...

Maybe you should trade pumps with Hollyfield

No kidding Sting!..Can you say: "Mirror Image Thread"?

well Sting..the results are in...sort of..

First off...Steamup was a huge help..you were right about him..he spent a lot of time going thru all the numbers that I fed him and graciously analysed them..

I did a heat loss on the house..I measure and calculated every piece of pipe and bend in every zone...got info on my air handlers...etc...

Prior to Steamups final thoughts, I got a deal on a Taco 0013 pump..got it below wholesale...Steams' recommendation was for a 009 or 0011..but today I was in experimentation mode and could not resist temptation..had to see what this pump would do..could always sell it and get my money back if it proved to be a problem..
So I swapped it out..big deal..15 minutes tops..

Soooo...today hit 48* out side..when I put it in it was 40*..basement zone had no heat on..stood at 56*...so I cranked that zone..and waited and watched...

Well..the pump works great without obvious issues..various noise, etc..the initial water going to the zone was going out at about 170*....comming back at 85..no prob..the pipes were ice cold..as I watched, other zones came on, and I watched the return temps climb until about 135, at which point those zones got satisfied, except the basement of course, and the return water temp. started to drop again...after a few hrs., the basement seemed to be at set point, but the return water temp was about 115...

Now all that time in the garage, I was a little chilly..thought "I'll fire up that wood boiler'..got it going full bore after a while...as it stands now, I have 2 boilers maintaining 145 gal of 205* water, idleing....42*out side...basement zone at temp, but always calling..new pump pumping away!

Return water temp 115...

Daughter came home and said "Dad! When are you going to put the heat on down there? my feet are freezing' !!! ...uuugghhh!!



and so it goes!..

stoker_RI wrote:now, I have 2 boilers maintaining 145 gal of 205* water, idleing....42*out side...basement zone at temp, but always calling..new pump pumping away!

Return water temp 115...

Daughter came home and said "Dad! When are you going to put the heat on down there? my feet are freezing' !!! ...uuugghhh!!

.

???? That zone is receiving 200 degree liquid and returning it from load to boiler at 115 ???? and the zone is cold

choke the flow to the other zones to increase the flow to the hi differential zone - this should do two things
1 the differential of supply/return should become less
2 more energy should transfer into that load because more energy bearing liquid is traveling the path --- so the area should become warmer - more comfortable

or the heat loss of that area out strips the radiation potential and a short term fix is to put several small slow speed fans on the radiators or fin tube - in effect making a poor mans convector - and that should transfer more energy into the room - but it should also lower the return temps - so rebalance the system by choking the flow to the other zones and AGAIN increasing the flow to the cold zone - now that written - 1/2 inch pipe will only carry so much energy, even above the accepted trouble free rates that you will/ may be forcing by "balancing" the flow as I suggest.

OR

you can only beat a horse up the hill so long and it will drop dead - this may be a lost cause - but didn't you say it all worked with the wood boiler?? If yes could it be because the wood boiler sent water higher than 200 degrees to that zone - this could also explain a lot and verify that the radiation of that area is vastly undersized.

Or I may be just rambling again about my navel --

Sting wrote: That zone is receiving 200 degree liquid and returning it from load to boiler at 115 ???? and the zone is cold

..well..not quite true..the water in the boilers is 200*..which gets pumped into the primary loop where it is mixed with the return water...so when it gets drawn out of the primary loop by the new pump (30psi) and to the heating zones, it is more like 185...the zone is not cold...it is def. improved...just calls for heat almost constantly to maintain and sends back 115 deg water..

-The baseboard output down there is about 31mbtu for a heated space of about 850 sq. feet..

-the pipe is 3/4" copper

Sting wrote:choke the flow to the other zones to increase the flow to the hi differential zone - this should do two things
1 the differential of supply/return should become less
2 more energy should transfer into that load because more energy bearing liquid is traveling the path --- so the area should become warmer - more comfortable

-i'm getting the biggest spread in differential when no other zone is calling!..when other zones call, the differential improves...!

Sting wrote: you can only beat a horse up the hill so long and it will drop dead - this may be a lost cause - but didn't you say it all worked with the wood boiler?? If yes could it be because the wood boiler sent water higher than 200 degrees to that zone -

-Yes..all worked fine before with the wood boiler..and I used to limit it at 180..(and I could get the room to 80 degrees)

The only variable is that the plumbing of the 2 boilers has been changed to a primary/secondary loop...and I HAD been up to today been using the same Taco 007 pump to supply the zones...which has been determined to be insufficient now..thats why I went up to this new pump that is vastly stronger..

-I suppose as a test I could put a ball valve on the primary loop and close it, effectively rendering it inoperable as designed...and check if I could get results as I had in the past...

-what kind of 'fans' are you talking about for the baseboad heat? I am not familiar with that...

Hmmm...you know..as I think about it...when I did the re-vamp of the pipes, I discovered that a couple of the Honeyell zone valves had issues that I fixed..the valve itself on the hw zone would not 'seat' fully, so I left the valve body and replaced the valve....and on the basement zone, I needed to replace the motorized head...
I'm beginning to wonder if I had a 'ghost flow' to the basement without an obvious call for heat...effectively sending heat down there whenever any of the other zones called...
does that seem plausable?

pm sent

Ok, this is rather late, and you may have solved the problem by now, and somebody else may have made a similar suggestion by now, but I'd think about an approach something like the following, (I didn't try to read all 74 posts in this thread):

1. Extend the existing basement zone to heat the new 15x20 office. UPDATE: I guess I didn't read the initial post carefully enough, I see now that the heating pipes for the existing basement zone go through the unheated area first, so, in general, my approach should still work--just add radiators in the unheated area. Heat used in the new area will reduce heat to the existing heated area without having to put covers over the existing radiators--the additional radiators will just result in a lower return temperature from this area (and less ability to heat this area, but with the Alaska Kodiak stove already in this area, it sounds like that won't be a problem, at least not very often.

2. Find ways to block the heat from being released from the existing radiators (convectors?) in the original section of the new combined basement zone. I think convectors sometimes have flaps to allow you to reduce the heat output. For radiators, you might build some kind of sheet metal (i.e., non-flammable) removable cover, possibly with some (non-flammable) insulation.

Then, as long as the existing zone does not require (much) heat, you keep those radiators covered and most of the heat goes through to the new zone. (In other words, as long as you run that other stove, or that area is not in use and doesn't need heat.)

When the original area needs heat beyond what the stove can provide, you can uncover one or more radiators to supplement the heat in that area.

Someone already suggested you make a calculation to see if the piping for the original zone can carry enough heat to heat the new area. You might still follow my suggestion even if there is not sufficient heat for the new combined zone, if the original area is not always "inhabited" or you can vacate your office or supplement the heat with some other heat source (electric, kerosene, propane) on a few very cold days per year.