Experimental install

[BrownianHeatingTech]

How much storage Joe? The grey tank is the exp tank? And the black tank is the storage?

The three dark grey tanks behind the boiler are the storage tanks. 220 gallons each, for 660 gallons total storage.

The light grey tank is the expansion tank.

What is the small black cylinder?

Duh - Shell/tube HX. I should think more and type less.

It's a Caleffi hydraulic separator, actually. There's a .pdf file describing how they work, here. Similar in principle to closely-spaced tees in a primary-secondary system, but including air and dirt separator into the same package.

Joe

 

[mysticfalcon]

Looks like a hydrolic separator to me.

 

[Jim K in PA]

How much storage Joe? The grey tank is the exp tank? And the black tank is the storage?

The three dark grey tanks behind the boiler are the storage tanks. 220 gallons each, for 660 gallons total storage.

The light grey tank is the expansion tank.

It's a Caleffi hydraulic separator, actually. There's a .pdf file describing how they work, here. Similar in principle to closely-spaced tees in a primary-secondary system, but including air and dirt separator into the same package.

Joe

Aha! Thanks for the link to the explanation for the hydroseperator. Very interesting option, and one that I am sure reduces install time and costs.

I did go back and re-read your OP and saw the storage volume. Sorry for making you repeat the info.

 

[Jim K in PA]

Hey Joe - any update on this install? How is the unit running? Issues? Success?

I sent you a PM too.

 

[Hydronics]

With respect to concrete: keep in mind that "3000 psi concrete" has a minimum COMPRESSIVE strength of 3000 pounds per square inch if cured under proper conditions.
For discussion purposes, a slab acts as a beam, under the load (tank weight) the top of the slab is in compression and the bottom is in tension. Concrete has very low tensile strength, this is why we place reinforcing steel and/or mesh in concrete. Rebar has 60,000 psi tensile strength (obviously much more than even the compressive strength of concrete). So, a small amount of steel placed in the tension portion of a beam can create a very efficient member.
Ultimately the allowable load carrying capacity in a slab does depend on many variables including the allowable bearing capacity of the soil beneath which can be only 2000 pounds per square foot (14 pounds per square inch).
It must be analyzed on a case by case basis. The more the load is spread out, the more the slab will carry (larger support under the tank). One thing to consider: if a failure means a crack in the slab, will that be an issue?

 

[TCaldwell]

joe, i would be curious about 02 percentages during different stages of the burn cycle, what their target % is and how it handles 02% towards end of burn, thanks tom

 

[BrownianHeatingTech]

Hey Joe - any update on this install? How is the unit running? Issues? Success?

The unit is running quite well. The only issue I had with the boiler was that the doors were a bit out of adjustment, so they didn't seal fully. They are adjustable, so it's just a matter of tightening them to seal better.

The cool thing about that is that we found the problem because the boiler announced on its display: "boiler has air leak." I'm rather impressed by what I've seen of the computer. It will be interesting to see what else it can do, when we actually have a proper manual for it.

That, and they include copious numbers of extra nuts, bolts, washers, screws, and the like, which is disturbing because it makes you feel like you must have missed something during assembly, but the folks at BioHeat assure me that the manufacturer just likes to include extra bits.

The biggest assembly warning I can give any other contractors installing these is that the air control rods (which connect the left- and right-side dampers, so both are actuated together) need to be inserted during assembly. Which means you need two or three feet of access to the side of the boiler, in order to align and slide the rod in. So, if the boiler will be placed too close to other equipment for that to happen, the rods must be installed before the boiler is slid into its final location. Don't ask me how I know that...

joe, i would be curious about 02 percentages during different stages of the burn cycle, what their target % is and how it handles 02% towards end of burn, thanks tom

I know that it's been running around 9-10%, when I've checked on it. I've never logged a full burn, though. I know that it's possible to do some data-logging (the control board actually has a serial port), but I don't know if anyone has done that and formatted it for distribution, yet. You might call the folks at BioHeat, but I'm not sure if they will have any information available.

Joe

 

[BrownianHeatingTech]

Interestingly enough, due to the heavy, wet snow last night, the customer had a power failure during a burn.

The bypass zone valve opened, and the natural convection kept the system from overheating. So I feel pretty confident recommending that as an alternative to a conventional dump zone, with the caveat that the piping size, pitch, and length must be carefully selected for it to work. There must be continuous slope upward from the boiler to the tank, on both the supply and the return, to avoid heat traps. That can be tight on the return, if the boiler is up on blocks (even with only 4" blocks). It also requires that a minimum of fittings and a high-CV valve be used, in order to avoid excess friction flow.

But it makes for a cleaner install, when the other factors allow.

Joe