wood/oil combo help

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vpantus

New Member
Sep 24, 2010
5
Windsor CT
Hello Everyone i need some help deciding what boiler to put in.

Currenty i have an oil boiler with a coil for domestic water. It is about 22 years old, as old as the house. The house is a raised ranch, 1700 square feet on the top floor, and about 1000 finished square feet on the bottom floor. The boiler is on the bottom floor and heats both floors.



Last winter we spent alot of money to heat the house, it is just me and my wife. We want to upgrade out boiler for this winter and need help deciding what to do.
We have alot of wood stackedup ready to be burnt this winter, and have resourses to get more. Therefor we wanted to install a woild/oil combo.
I have researched online and found the Atmos DC 32 SPL . it seems to be a nice wood oil combo. it is glassification. It is made out of steel and not cast iron, can someone tell me which is better? Does anyone have any reviews on this boiler? .



One of the problems we have is that the boiler room is small, and there is only one flue, and enough room for one boiler (barely). WIth the set up of the house there is no where else to put in another boiler without having to make another flue/chimney. we do have room under our stairs to install a water tank for domestic hot water which would help during the summer.



Attached is a picture of my current boiler set up and how i was thinking to install the Atmos DC 32 SPL . it is kind of tight though.


So the options are: Atmos DC 32 SPL/ another wood oil combo that someone can recomnd/ or replace with just oil boiler (but if i go with this option, will it really be worth it? will it be that much more efficent then my current one?(i think it is about 86% effciency according to my hvac guy))

If anyone can share thier thoughts on our situation that would be great!
 

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Forgive me for my "sacriligeous" comments but

For what its worth have you considered trying to reduce your heating load by efficiency improvements yet? I am not familiar with the details, but CT appears to have funding for energy efficiency improvements http://www.cl-p.com/Home/SaveEnergy/Rebates/HomePerformanceProgram.aspx that may be worth researching prior to switching to a wood oil combo.

I am not familiar with the latest wood oil combo units, but the ones that I have run onto over the years have been compromises usually biased towards burning wood. The oil side works but the overall seasonal efficiency is marginal as the oil boiler usually ends up having to heat a large volume of water that is used on the wood side. This is okay in the winter but leads to a hot basement in the spring and fall. If you are willing to make a long term commitment to heating primarilly with wood, the long term lower effective efficiency of the oil combo may be acceptable, but realize that you arecommiting yourself to 4 or 5 cords of wood per year (depending upon whose table you use, 1 cord equals 100 gallons of oil) It also ruins the efficiency of putting in a "hot water maker" hot water tank that is fed off a zone on the boiler. An alternative may be to put in a "system 2000 type" cold start boiler, the actual boiler is the size of a dorm refrigerator and the units can be vented through the wall with no flue in many juristictions by the installation of a power vent. That would free up flue for a supplemental wood stove. If you have concern for power outages, the wood stove is a great backup heat and cooking source is the power goes out.

The other thing to check is your flue condition and diameter, many wood boilers require an 8 " flue and some oil flues are smaller.

The 86% efficiency mentioned by your burner tech is about as good as it gets with oil (I assume you dont have a natural gas options). Unfortunately the efficiency quoted is how much of the heating value of the oil is converted to heat in the boiler. What you really want to know is how much of a gallon of oil is going to lead to useful heating of the house and unfortunately that is specific to your house, although the AFUE ratings (annual fuel utilization efficiency) is an attempt at standardization. Switching from a continuously hot oil boiler with a "tankless hot water coil" to a cold start with appropriate outdoor reset controls and a separate hot water maker may give you a 20% reduction in oil use.
 
peakbagger said:
Forgive me for my "sacriligeous" comments but

For what its worth have you considered trying to reduce your heating load by efficiency improvements yet? I am not familiar with the details, but CT appears to have funding for energy efficiency improvements http://www.cl-p.com/Home/SaveEnergy/Rebates/HomePerformanceProgram.aspx that may be worth researching prior to switching to a wood oil combo.

I am not familiar with the latest wood oil combo units, but the ones that I have run onto over the years have been compromises usually biased towards burning wood. The oil side works but the overall seasonal efficiency is marginal as the oil boiler usually ends up having to heat a large volume of water that is used on the wood side. This is okay in the winter but leads to a hot basement in the spring and fall. If you are willing to make a long term commitment to heating primarilly with wood, the long term lower effective efficiency of the oil combo may be acceptable, but realize that you arecommiting yourself to 4 or 5 cords of wood per year (depending upon whose table you use, 1 cord equals 100 gallons of oil) It also ruins the efficiency of putting in a "hot water maker" hot water tank that is fed off a zone on the boiler. An alternative may be to put in a "system 2000 type" cold start boiler, the actual boiler is the size of a dorm refrigerator and the units can be vented through the wall with no flue in many juristictions by the installation of a power vent. That would free up flue for a supplemental wood stove. If you have concern for power outages, the wood stove is a great backup heat and cooking source is the power goes out.

The other thing to check is your flue condition and diameter, many wood boilers require an 8 " flue and some oil flues are smaller.

The 86% efficiency mentioned by your burner tech is about as good as it gets with oil (I assume you dont have a natural gas options). Unfortunately the efficiency quoted is how much of the heating value of the oil is converted to heat in the boiler. What you really want to know is how much of a gallon of oil is going to lead to useful heating of the house and unfortunately that is specific to your house, although the AFUE ratings (annual fuel utilization efficiency) is an attempt at standardization. Switching from a continuously hot oil boiler with a "tankless hot water coil" to a cold start with appropriate outdoor reset controls and a separate hot water maker may give you a 20% reduction in oil use.

Thanks for the Input, I Installed Effiecent windows last year before the heating system, didnt help alot. This year i installed siding insulation, so i hope that will help a bit. New doors too.

The cold start boiler may be a smart way to go. I was looking around and found some ideas to have a wood glassifcation boiler, and maybe a small cold start boiler. The only thing is will i be able to fit the two in my small boiler room? There is deffinetly room to power vent it outside.
 
I would think the improvements you have made to the house will be appreciated this year. I also looked at the Atmos boilers since we also were looking for a wood/oil boiler with one flu available and also limited space. We went with a Wood Gun partly due to their facility being fairly close to us and partly due to the overall build. I have read some good things about the Atmos in here. I'm not sure but I believe the Atmos and Tarm units would not fit in our basement bulkhead which was a shame as the Atmos was less $$!
We have 1 winter under our belts so we are still fairly new at the game. We only use the oil side when we are not home for extended periods of time(normally long weekends) and we are happy with the efficiency of the wood boiler itself.
 
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