Problem, not sure what size to get.

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ryooper

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Dec 18, 2013
49
centralu.p.
Ready to pull the trigger and get a gasser, not sure what size to go with, going to get an Eko but do I get the 25 or the 40? Talked to New Horizon they said either would work have 2800 sq. ft. will be putting in 500 gals. storage. Just wondering if the 25 would be a little under sized just redid heat loss calc and came up with75,000 btu/hr. loss. If I can get by with the 25 without burning a lot more wood saving a little more money would be great. Just looking for some educated advise thanks.

Ryan
 
75k btu/hr heat loss? Is that your average or peak? If that's anything near average you'd likely be undersized even with a 40KW if your plan is to install storage and start batch burnining eventually.

Tell us a little about your house. My 3200 square feet averages closer to 20k btu/hr, peak of double that +/-. I sometimes wish I had a 60KW for quicker storage charges.
 
your 500 gallon storage will also be too little for the size of the house and size of the boiler. 25 KW will be too small.
 
stee6043 said:
75k btu/hr heat loss? Is that your average or peak? If that's anything near average you'd likely be undersized even with a 40KW if your plan is to install storage and start batch burnining eventually.

Tell us a little about your house. My 3200 square feet averages closer to 20k btu/hr, peak of double that +/-. I sometimes wish I had a 60KW for quicker storage charges.
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Well like I said 2800 sq. ft. it was built in 83 have a fair amount of sealing up to do newer windows some added insulation, previous owners started putting new siding on have to finish
back side yet just house wrap and the 1/2 in. foam board ins. on entire backside. have old boiler sys. now with water to air hx.
 
Fred61 said:
your 500 gallon storage will also be too little for the size of the house and size of the boiler. 25 KW will be too small.
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I don't know if I can get any more storage than that? Maybe some what limited budget right now would the 500 be more compatible with the 40?
 
stee6043 said:
75k btu/hr heat loss? Is that your average or peak? If that's anything near average you'd likely be undersized even with a 40KW if your plan is to install storage and start batch burnining eventually.

Tell us a little about your house. My 3200 square feet averages closer to 20k btu/hr, peak of double that +/-. I sometimes wish I had a 60KW for quicker storage charges.
Click to expand...
On the heat loss that I am assuming peak I had design temp at -21.
 
I have a 200k boiler with 1000 gallons of storage with a peak heat loss at about 45k btu/hr. I also have forced air with a heat exchanger. Most of the winter I had 2 small fires a day to keep hot water at the top of tank.

With your heat load and 500 gallons of storage I would consider that a buffer tank not a storage. You could run it non stop most of the time especially if you had a 25Kw boiler. Just remember if you truly have 75k demand you might be running your backup also at peak demand, the 25kw boiler is at max. It will average less.

gg
 
I have an EKO 25 and it heats my 2200 sq. ft ranch and 9' ceilings very easily. I have no storage. My btu is about 25k @ 0 degrees. With a 75k btu , that is 3 times my heat load. I don't think you're heat load is tha high, even in Da U.P. unless yor house is a sieve. My 25 would never idle at that rate but it would work. Bare minimum though.
 
goosegunner said:
I have a 200k boiler with 1000 gallons of storage with a peak heat loss at about 45k btu/hr. I also have forced air with a heat exchanger. Most of the winter I had 2 small fires a day to keep hot water at the top of tank.

With your heat load and 500 gallons of storage I would consider that a buffer tank not a storage. You could run it non stop most of the time especially if you had a 25Kw boiler. Just remember if you truly have 75k demand you might be running your backup also at peak demand, the 25kw boiler is at max. It will average less.

gg
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O k thanks maybe I m doing something wrong with the heat loss calc seems every time I do it it comes out different. With some of the R values I m guessing not sure the exact on some of them. I guess I should do some more home work on that thanks again.
 
ihookem said:
I have an EKO 25 and it heats my 2200 sq. ft ranch and 9' ceilings very easily. I have no storage. My btu is about 25k @ 0 degrees. With a 75k btu , that is 3 times my heat load. I don't think you're heat load is tha high, even in Da U.P. unless yor house is a sieve. My 25 would never idle at that rate but it would work. Bare minimum though.
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Ya I m sure that cant be right house seems to be fairly tight, it has some upgrades newer windows and added ins. Trust me I m no expert when it comes to figuring out the heat loss and loads all kinda Chinese to me lol. But I m trying to educate myself with the help from everyone here on the forum.
 
ryooper said:
I don't know if I can get any more storage than that? Maybe some what limited budget right now would the 500 be more compatible with the 40?
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No! The minimum I would go with the 40 is 1000 gallons. Even if your heat loss is less than calculated, a 20kw Eko will need to be fed at least every 4 hours. It has a pretty small firebox.
 
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I'd spend more time to make sure I get my heat loss right.

500 gallons isn't a terribly bad match for a 25kw boiler (but more is always better), but a 25kw boiler might be a bad match for your heat loss. Then if you up to 40kw, your storage is getting to be on the small size.

I've got a 40kw boiler, and 660 gallons of storage. 2700 sq.ft. 20 year old two storey on a windy hilltop. I'd like to have more storage, but my boiler is big enough for me. Worst case coldest winter days I burn 12hrs/day, but more typical is 6 hrs/day.
 
It would help to insert past usage of fossil fuel to give you an idea of heat loss. Past experience in the building trade has prompted me to determine that the amount of insulation in a building can be compromised by the quality of the installation and flaws in the envelope design can cause the heat loss calculation to be a moving target.
 
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...the amount of insulation in a building can be compromised by the quality of the installation and flaws in the envelope design can cause the heat loss calculation to be a moving target.
Click to expand...

Indeed!
 
I have about same size house and I would go with the 40 for sure. You want the extra capacity to be able to heat your storage and the house at the same time. I have 500 gallons with my EKO 40 and find that its a little to small. I can get 10-12 hour reload times with it.
 
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maple1 said:
I'd spend more time to make sure I get my heat loss right.

500 gallons isn't a terribly bad match for a 25kw boiler (but more is always better), but a 25kw boiler might be a bad match for your heat loss. Then if you up to 40kw, your storage is getting to be on the small size.

I've got a 40kw boiler, and 660 gallons of storage. 2700 sq.ft. 20 year old two storey on a windy hilltop. I'd like to have more storage, but my boiler is big enough for me. Worst case coldest winter days I burn 12hrs/day, but more typical is 6 hrs/day.
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I agree after some further research I was able to get ahold of original owner he actually has all of the blueprints and specs for the house, all add ons and what not, so I will put this all together hopefully tonight, see what I come up with.
 
Hello ryooper. I use an EKO 25, bought it cause it can handle the load here and it was $4100 delivered. If I were to do it over with the experience I have now, I would go with the 40. If you have too much spare time the 25 would be ok for you. If not, you would find that the 25 will take more of your time to load, tend and reload. The 40 could most likely get your storage charged with on filling of the firebox.
 
O k after getting all my R values in order here I came up with 44,000 peak btu/hr. at -20, and I found another 500 gal. tank for storage so I would have a 1000 total.
So I guess I will probably go with the 40. Thank you everyone for the input.
 
ryooper said:
O k after getting all my R values in order here I came up with 44,000 peak btu/hr. at -20, and I found another 500 gal. tank for storage so I would have a 1000 total.
So I guess I will probably go with the 40. Thank you everyone for the input.
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Good choice! You won't regret it. Now the fun begins:eek:
 
40k eko is what i have with a 70k btu design home and a 35k btu shed where it sits. I get about 6-7 hrs on a -10 to -15 day which is more like 80kbtus in my opinion but
I think you will be very happy with a 40 and 1000gals of storage
 
rkusek said:
40k eko is what i have with a 70k btu design home and a 35k btu shed where it sits. I get about 6-7 hrs on a -10 to -15 day which is more like 80kbtus in my opinion but
I think you will be very happy with a 40 and 1000gals of storage
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Just found out about a Biomass 60 Used 5 yrs. old don't think I want used though.

Ryan
 
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