EKO or Econoburn?

[heaterman]

IIRC, Garn's storage capacity is based on an 80* temperature drop so let's say for the sake of discussion your talking about 200-120* which is still plenty usable for an in slab radiant floor such as Father John has. If 90,000 is an average heat loss, I'd say it's safe to assume a cycle time of 10 hours on average. More in mild weather and less at sustained design conditions. The lowest design temperature for Virginia I could find on my heatloss program was 10*F. I'd guess 90-110K is going to be close to real world conditions for the monastery.

 

[Nofossil]

IIRC, Garn's storage capacity is based on an 80* temperature drop so let's say for the sake of discussion your talking about 200-120* which is still plenty usable for an in slab radiant floor such as Father John has.

I'm not familiar with the Garn design, but 200 degrees seems really high for a storage tank. Does the Garn idle when the tank is up to temp? Otherwise, it would seem that you're at some risk of boiling if you put a bit too much wood in it.

My tank is external, and my boiler outlet is around 185 max. I've never gotten the average tank temp above 165 or so. If the Garn can reach an average tank temp of 200, that's pretty impressive.

 

[heaterman]

200* is not a problem because with 1,500 gallons of integral storage, it still requires a bunch of BTU's to push the water temp up to 210*. There is no "idle" with a Garn. It's either at full burn or off. Idle in a Garn is when you are simply using the heat stored in your water which can happen even with a stone cold firebox.

You are correct and prudent in keeping your EKO and remote storage at the temps you indicated. A safety factor of 30* is a good thing in my humble opinion.

(1,500 x 8.33 x 10*) = 124950 btu

 

[Father John]

It looks like we are going with the GARN. They gave us a price we couldn't refuse, as I found it would be impossible to put together a decent gasifying boiler and similar sized tank with all the odds and ends and come out ahead. This is in spite of very generous discounts from Econoburn, Eko and STSS.

The model is the 1500, which has about 1420 gallons water storage and is rated at 350,000 Btu/hr. The big question now will be whether we should cut into our current boiler loop and redo so that the GARN is feeding the radiant zones directly, or use a heat exchanger. My understanding is that piping directly will allow us to draw more usable heat out of the storage tank, maybe even down to 100*. It will be a pity to have to redo the piping, but if it makes sense in the long run, it has to be done.

By the way, I found the fuel records, and it turns out we averaged 50,163 Btu/hr in Nov-Jan last winter, which was unusually mild, with the average in Feb-Apr going up to nearly 90,000 after we got the library zone hooked up and the weather got much colder.

 

[Gooserider]

Sounds like a garn good decision..... :lol: (Couldn't resist....)

As to the plumbing, I'm not an expert, but I would see if Garn had any specific advice as my first approach. If they didn't, I would say that if the Garn is providing pressurized storage, then go with direct piping, if it is non-pressurized, go with the heat exchanger... I shouldn't think it would involve all that much cutting into your existing plumbing either - I assume you already must have some sort of inlet and outlet manifold to tie your existing boilers together and into the circulator loops, I'd just add another connection into that piping.

Gooserider

 

[Happy]

I am also trying to order Garn boiler.I left several messages at their phone no. for last 10 days.I got 1 response back 3 days ago saying some salesman will contact me from my area.They did not give me contact information for this salesman.Now I am waiting for his call for last 3 days.I understand it takes 6 weeks for delivery and I have to decide fast if I want to wait longer for Garn or go with Orlan EKO.Garn has great product but if they are not ready to sell then it is just imaginery product for me.I talked to Tom from CT in detail about Garn who is using it and I am impressed.I am posting here and hoping to get some other contact information to one of the local salesman in New England.Do anyone know cost of Garn 2000 ? I have read on some other thread that it is close to $12,000. What are other cost I should expect.I currently have my 350k oil boiler in basement of main building.Oil boiler directly feed baseboard heat for 7000 sf building.It also heat two 80 gallons DHW tanks via one flat plate HX.The garn will be in my car garage.Two boilers will have distance of about 80 feet.But the distance between two Building is only 30 feet.So my understanding is I will need underground piping for only 30 feet.Tcoldwell, is it possible for you to post rough diagram for your system or pictures of your system? In future I will also have about 3000 gallons of hot water storage in my existing 21'x10'x5' concrete tank.I will have to insulate it and build a partition in the middle to seperate cold and hot water storage.

P.S. - I just got call from Garn when I was writing this post.They gave me local contact no. for chris from floor heat systems.I am going to call him.