BTU Calculations

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MaverickM23

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Jan 8, 2013
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I don't have a heat loss for my house but I do know how many BTU's Im using by doing the math 1 gallon oil = 136,000 BTU's. So in November and December I used 223 gallons or 497,180 BTU's a day. And now in colder January I used 170 gallons or 745,806 BTU's a day. Heres my question why are all the boiler companies telling me I need the bigger Model. If I look at the Empyre Elite 100 with a 66,000 BTU per hour burn if I run it twice for 8 hours that would be 1,056,000 BTU's plenty more than I need. The 200 would be 1,760,000 BTU's for two 8 hour burns. Is my thinking correct here or am I looking at this the wrong way?
 
I don't have a heat loss for my house but I do know how many BTU's Im using by doing the math 1 gallon oil = 136,000 BTU's. So in November and December I used 223 gallons or 497,180 BTU's a day. And now in colder January I used 170 gallons or 745,806 BTU's a day. Heres my question why are all the boiler companies telling me I need the bigger Model. If I look at the Empyre Elite 100 with a 66,000 BTU per hour burn if I run it twice for 8 hours that would be 1,056,000 BTU's plenty more than I need. The 200 would be 1,760,000 BTU's for two 8 hour burns. Is my thinking correct here or am I looking at this the wrong way?
You are correct. I don't know why they are trying to sell you a larger unit unless just to make more money. It's not a good idea to oversize as the boiler would spend too much time idling. I was heating a 2700 square foot log home and 400 square foot shop with a 100 and it was not running right.
 
You are correct. I don't know why they are trying to sell you a larger unit unless just to make more money. It's not a good idea to oversize as the boiler would spend too much time idling. I was heating a 2700 square foot log home and 400 square foot shop with a 100 and it was not running right.

So what did you end up doing? Are you still running the 100 or was it too small?
 
So what did you end up doing? Are you still running the 100 or was it too small?
I had purchased an early version of the Elyte 100 in Dec. 2010. It had some serious design faults which I believe they have now corrected. Go to the Empire Elyte Boiler corrosion thread on this forum for a more involved discussion. Even though my unit was defective, causing less than advertized performance and ultimately premature failure it was adequate to meet my needs right up till it failed. From what I could tell it was running at about 50% of it's capability. If you note near the end of the thread it appears they have addressed the issue in the newer units. I'm currently fighting for my warranty rights. They were never forthcoming about their problems or my problem could have been avoided.
 
One guy told me I needed the EKO 40. The guy I bought it from ( Mark from AHONA) said all I need is a 25. He was right. I'm glad I didn't spend the extra 500 bucks. It would just idle more anyway.
 
One guy told me I needed the EKO 40. The guy I bought it from ( Mark from AHONA) said all I need is a 25. He was right. I'm glad I didn't spend the extra 500 bucks. It would just idle more anyway.

Sounds like I need to give him a call and discuss my situation with him. Just curious how are you heating your house with the EKO, HWBB, do you have a backup oil burner or something else? Im doing some more reading where they are telling me its not efficient to use the typical high temp fin type baseboards with a wood boiler.
 
I am heating it with a Heat exchanger in the furnace. When it calls for heat the fan goes on and it's forced air as usual. My hot water has a gravity feed hooked up with the boiler. My back up is just natural gas with the forced air. Marks number is 1-607-965-8101. He is just south of Utica New York. His price was good including delivery.
 
I am heating it with a Heat exchanger in the furnace. When it calls for heat the fan goes on and it's forced air as usual. My hot water has a gravity feed hooked up with the boiler. My back up is just natural gas with the forced air. Marks number is 1-607-965-8101. He is just south of Utica New York. His price was good including delivery.

I have been looking at the EKO and I like the simplicity of it. I feel that if I size the boiler right it will run efficiently most of the time since I don't plan on doing storage. How much are you heating with your EKO, square footage wise? I also like the prices Im seeing on the EKO's especially when compared to other models. I know the WG and Empyre are suppossed to relite themselves if they go idle, how does your EKO do if it idles?
 
Don't be fooled by the re-lighting claim. Think about lighting a fire with a hot brick. It's not happening!
 
Don't be fooled by the re-lighting claim. Think about lighting a fire with a hot brick. It's not happening!

I know its hard to imagine but some say it works. I need to have a boiler that will keep working by itself even if it idles a little bit. I am away all day teaching and no one else is at my house. Was reading about the wood gun with the timer that will run it every so often to keep the fire going, didn't know if the EKO or any others have anything else like that.
 
I know its hard to imagine but some say it works. I need to have a boiler that will keep working by itself even if it idles a little bit. I am away all day teaching and no one else is at my house. Was reading about the wood gun with the timer that will run it every so often to keep the fire going, didn't know if the EKO or any others have anything else like that.

I had a Wood Gun, ran it for eight years. I know what "some say". Most are in their first or second year of operating their units and are still convinced the fire shuts off and the hot cement re-lights the wood. When an oil boiler "shuts off" it is done by removing the fuel supply, same goes for a propane water heater "remove fuel =no fire, my diesel tractor, same thing, remove fuel firing stops. In these boilers the fuel is still there smoldering and hopefully there's still a small ember in order for the fire to re-kindle. Do you think the cycle timer these guys are installing is keeping the refractory hot enough to ignite the fire or is it keeping the coals glowing just enough to build upon adding air flow.
Nearly all of the most popular boilers except for a couple that are talked about on this forum will go into idle mode and re-light.
 
I have the Econoburn 200 that I ran the first season without storage and this is my second season with it. They will idle but it is so convenient with storage I would never want to run without it again.


That being said the Econoburn will do a 15 second fan cycle every 15 minuts to keep live coals. The winter that I ran without storage I never had the fire go out and not restart when needed. But it is never out the fan keeps a coal bed. No magic here you need O2, heat, and fuel for fire.

Gg
 
Keep in mind that unless the specs say otherwise, rated output is maximum output which may be reached during the "high burn" of the wood load. A more realistic number would be "average" output, which takes into account the much lesser output on the start of the boiler before it reaches high burn and the ever reducing output from high burn to the wood load burning down to coals and the boiler is ready for a reload. Probably 60-75% of rated output would get in the range of average output. So, a 140,000 btuh rated boiler may produce on average 80-100,000 buth output.
 
My experience is that the average output over the course of a fire is about 75% of rated output (peak output exceeds rated output by a bit).

Average winter day for me is 15k BTU/hr or 360,000 BTU. That works out to about six hours worth of fire at 60,000 BTU/hr. On a really cold day I need 12. During the burn I heat up the house, hot tub, hot water, and finally storage. Between burns storage keeps everything comfortable, though I do let the house temperature drop one or two degrees when heating from storage.
 
Don't forget to polish up the crystal ball real good and evaluate the possibility of future expansion or storage addition before ordering the new boiler - might be better off in the long run going one size bigger. Also, going oversize on the boiler is less of an issue if you're doing storage at the same time. If you determine no storage or future expansion possibilities, you're likely on the mark with your thinking.
 
Keep in mind that unless the specs say otherwise, rated output is maximum output which may be reached during the "high burn" of the wood load. A more realistic number would be "average" output, which takes into account the much lesser output on the start of the boiler before it reaches high burn and the ever reducing output from high burn to the wood load burning down to coals and the boiler is ready for a reload. Probably 60-75% of rated output would get in the range of average output. So, a 140,000 btuh rated boiler may produce on average 80-100,000 buth output.


^^^ what he said ^^^^
 
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