HELP! Plumbing Closed loop wood boiler to indoor boiler

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Jcc583

New Member
Nov 30, 2018
60
New York
Good afternoon I’m having some trouble with plumbing my closed loop wood boiler into my indoor propane boiler. I have a 125 gallon buffer tank and my design is based on the simplest pressurized storage sticky. I think I piped my supply and return into poor location. I almost think I need to flip flop them. My wood boiler is 50’ away in an outdoor wood shed. The lines are 1 1/4” O2 barrier pex. I started with 300 gallons of storage but had issues so I now have 125 gallons and will be adding another 125 soon. I may have had an air lock issue but I couldn’t get my supply line to pump hot water into buffer tank. The return kept getting hotter and hotter and yes I triple checked my plumbing. My pictures will hopefully explain better. You will see my return for buffer is piped into my return manifold right before the pump, I think this is working against me! I appreciate all help!!!
 
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Why are the two valves closed?
 
Or are there four valves closed?
 
So what controls the circulation pump? Aqua stat turns pump on at certain temperatures?

Sorry. I’m no plumbing expert. Just trying to see where everything goes in pictures is tough. Maybe a little more explanation of how System works will spark someone to ask the right question (s). ?
 
I had mine plumbed like simplest pressurized storage sticky as well. Plumbed in parallel to oil boiler.
 
So was there heat demand from somewhere to turn circulating pump on?
 
I’m really hoping someone who knows much more than I do about this chimes in! LOL

How much do you know about this stuff? Is this your first time doing this?
 
I ran with and without a call. It’s ran by a taco 501 and a r89a with a break on rise aquastat. All zones are ran parallel, end switch’s powers load circulator and oil boiler based on aqua.
 
You might need to clarify some things. Like - what is the exact problem? I think you said can't get wood heat to buffer. But you also said return gets hot? Which sounds like heat is going thru buffer? Kind of hard to follow piping flows in pics. Can you add arrows? But I see a couple of high spots that would make real good airlock spots, with no bleed points.
 
This shows flow bleeders and air separaters. Thanks!
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I was also concerned with this return manafold and my position next to pump. I was thinking that pump could create a pull on my buffer return line. As my wood boiler climbed to around 260• my oil boiler ended up blowing off at the pressure relief valve!
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Other thought is maybe my three speed pump from boiler was pumping directly to system and not cycling through buffer as designed. Just throwing thoughts out.
 
Think you need to go one step at a time.

My first step would be get the wood boiler going, open the two ball vales on the pex coming in, & observe what happens.
 
Other thought is maybe my three speed pump from boiler was pumping directly to system and not cycling through buffer as designed. Just throwing thoughts out.

That would mean your wood heated water is going right to your system when it is needed. Which I wouldn't call a bad thing?

Might still be my eyes, but I still am not seeing bleed points on those two high loops to the right of the tank.
 
And which way are those check valves allowing flow? I haven't checked out that sticky for a long time, but something isn't looking quite right there.

I have to go out for most of the day though so won't be back to this for quite a while.
 
I tend to think it might be the above thought. Also I believe the purge valves are on the wrong side of the ball valves on the zone returns, if you opened the purge valves you’d be purging the boiler instead of the zone.
 
To start, the tees in the storage are oriented wrong. Should be a straight shot from wood boiler to storage. Supply and return to house should be going up from tees. Next, it looks like a big air trap where the circulator is with no way to vent. Those are a couple places I would start
 
To start, the tees in the storage are oriented wrong. Should be a straight shot from wood boiler to storage. Supply and return to house should be going up from tees. Next, it looks like a big air trap where the circulator is with no way to vent. Those are a couple places I would start
So I need to turn the tees towards the direction of the wood boiler and add a air vent in top section of load supply? Is the supply and return from storage into house manifold the correct idea?