Replacement needed for wood/oil boiler

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PA Fire Bug

Feeling the Heat
Jan 13, 2010
313
Blair County, PA
We are heating our house with a Riteway wood/oil boiler manufactured in 1979. This is our 6th year in our house but the first year that we have burnt wood in the boiler. My wife was afraid that I'd burn down our house. At the start of the heating season, I turned off the oil valve leading into the furnace and fired up a wood fire. It is great to have heat to our hot water baseboard radiators throughout the house but the boiler is terribly inefficient. It takes nearly 30 minutes with a roaring fire to heat the boiler temp. to 140 to kick on the hot water circulation. There also is no automatic temperature control for the wood fire. The air intake must be changed based on the temperature and pressure of the boiler which doesn't work well during the night. The guy who had the boiler installed said that once we burn wood, we will need to clean or replace the oil valve because it becomes dirty. We want to replace the boiler with a more efficient boiler that burns both wood and oil. Should I look for a combo boiler or buy two separate boilers? Our current furnace/boiler only has one flue with the wood and oil venting through the same pipe. I found this forum while searching for info on the Benjamin CC500. Thanks for the helpful information.
 
There are a number of manufacturers that make multi-fuel systems. I am not sure how they handle the single flue issue though. Generally it is not deemed safe to share the flue between wood burning and fossil fuel burning. You can direct vent the fossil boiler though and just use the flue for the wood boiler.

You have a number of options though. You are dealing with 30 year old technology right now and if you replace this boiler with a non-gasification one, you will likely still be using the same technology just newly constructed. I would suggest looking at gasification boilers and instead of mulitfuel or a second bioler, do what nofossil and perhaps some other have done and put in an on demand unit that can supply heat incase the wood goes out or can't keep up. Heat storage could be added up front or later to make loading times more flexible and to supply hot water year round.

If you give us some specifics on square footage, insulation, age of construction etc., we can probably give you some more specific suggestions.
 
Welcome to the forums - if you use the search, you will find a fair bit of discussion on the topic. The number of options for high efficiency gasification boilers that can also do fossil fuel are limited, and expensive, plus you tend to compromise on the performance of one fuel or the other, and also lose some of the redundancy you can get with separate units.

Oil boilers can be powervented through the walls of the basement, so what I would tend to suggest, based on the limited info you've mentioned, is looking at a gasification boiler w/ storage to hook up to the main flue, and then get a separate low cost powervent oil burner and stick it out the wall.

This would be a fairly high up-front cost system, but probably your lowest long term operating costs.

Gooserider
 
Firstly, welcome to the Forum :) I ditto your wife's concern . . . don't burn the house down!

I take from your post that you have hot water heat (Radiant or baseboard). Though I am far from an expert, my opinion would be to stay away from a combo unit. For backup there are some inexpensive options. And with adequate storage, you might not need backup.

Will you put the wood-fired hydronic within the residence? or in detached space? Pros and cons with each.

Jimbo
 
I have the benjamin CC 500 and am going to replace it. I am leaning towards a wood gun 140 or 180. My house is 3800sf with basement and garage. I currently do not burn oil in the benjamin and it will only keep up to the demand of heating 1 zone with 2 bedrooms (200sf) and our domestic, but to be fair I don't feed it the way it wants to be fed, I could add wood every 2 hours . The rest of the house is heated with a wood stove. The benjamin's wood output is only 80000 BTU's and the oil is 99-115000 depending on the nozzle. It might be fine for a smaller house but our is just too big for it. The benjamin currentlu uses ~9 cord and the wood stove uses 2-3 cord.
 
The Tarm Excel is a dual fuel boiler that may meet your needs. The Excel is a Solo Plus wood gasification boiler with a mid-efficiency fossil fuel boiler attached to the back. The Excel is a good option if you have a fossil fuel boiler that needs to be replaced anyway AND you only have one flue. This boiler is specifically designed to run two different fuels (wood and oil) up one chimney which, as WNO points out is normally not allowed. If you have two flues available, your are most likely better off with two separate boilers (one wood boiler and one oil boiler) instead of a combination unit. As others have mentioned, another option is to use your one available flue for a stand alone wood boiler and powervent the fossil fuel boiler out the side of the house (kind of like an overgrown dryer vent). I would add, however, that most of the contractors I speak with do not like powerventing oil boilers, so if you are inclined to powervent, then I would recommend you consider a propane boiler instead of oil.

I believe Wood Gun also makes a dual fuel boiler where the wood side is a gasification boiler. All others that I am aware of are traditional wood boilers like the one you already have.

Hope this helps.

Chris
(trying to walk the line between being helpful and blatant self promotion - sorry if I cross it occasionally)
 
BioHeat Sales Guy said:
Chris
(trying to walk the line between being helpful and blatant self promotion - sorry if I cross it occasionally)

As long as you keep giving good advice like this, Chris, we're going to cut you some slack. I think you pretty much covered everything I was going to say. I would reiterate that if you have two flues available, you will be way ahead to buy a dedicated wood gasification boiler and a cheap oil or gas backup.
 
Never did a complete scientific analysis of the efficiency of the oil side of my Wood Gun 140 but my "seat of my pants" analysis indicated that it was hogging allot of oil for a small amount of heat. Another downside was that when I was going to be away for several hours I would set the oil to come on at a boiler temp of saay 130 °F and just get home in time to see that the oil had just been running and heating 80 or so gallons of water up from 130 °F to 180 °F with no benefit to me. This happened several times but I still continued the practice since I didn't have any idea what the demand was going to be nor how long I would be away. If the oil were a separate unit, I could have maintained my house temp and not heated 80 gallons of water with oil.
 
Thanks for the advice regarding avoiding non-gasification boilers. I had never heard of wood gasification before I started researching boilers online. Now I realize that our current boiler and other new boilers that are non-gasification are allowing a lot of hot air to escape up our chimney. That would explain why I have burnt through several pick up loads of wood over the last month. I also had never heard of direct venting an oil burner. We would not want to do without an oil burner since we have a tank with a couple of hundred gallons of oil in it and would would not want to be without an oil burner when the time comes to sell our house (not any time soon). After spending some additional time looking online for wood/oil boilers, I was surprised at how few options exist. If an oil burner can be power vented without installing an additional flue, it sounds like having a wood boiler with a separate oil burner may be our best option. Most sites did not post prices but I'm afraid that the HS Tarm Excel is probably out of our price range.

Our house is 30 years old and is fairly well insulated. It is a split level with three bedrooms and two bathrooms in the upper level. The main floor has a kitchen/dining room and living room. The area to be heated is about 1500 square feet. Nearly half of the basement is finished. We use a coal stove to heat the finished basement (the chminey is on the opposite side of the house from the furnace chimney). It provides enough heat for the finished basement and bedrooms during the spring and fall. The old boiler is in the unfinshed basement which is not heated.
 
Aroth,

We are on our second season with an Tarm excel 2200. We haven't had to use the oil "side" of the boiler yet. We haven't need to. I am thrilled with the performance of the wood gasification side. I heat about 4,200 sqft and the 2200 handles that well. For 1,500 sqft the 2000 would work. We didn't have an option for a second flue or power venting. Yes they are spendy, but well worth it.

Good luck

LarryD
 
Hi Aroth,

Those with smaller, well-insulated houses are likely to just not see a payback to putting in a good (i.e. gasification) wood-fired boiler. And as you have learned, having a bad one is no savings either given the amount of wood they burn and other downsides. I have a 1250 square foot home that is well-insulated, and would love to go the wood gasification boiler route, and maybe some day I will, but it won't be because I will have a good return on my investment - I just don't burn enough oil to make it cost-effective, even with oil at $4 or $5/gal.

Other options - get a newer fossil-fueled boiler (heresy, I know) that is super efficient, or get a woodstove in your living area. I did the latter for now, and will wait to upgrade the fossil boiler until I really get over my fixation on getting a wood gasification boiler. I
 
Thank you everyone for the good advice. After discussing various options with my wife, we agreed that the lack of a readily available wood supply would increase the return on investment time on a wood boiler. I should've mentioned in my first post that we are hauling wood from my wife's parents who live 60 miles away. The wood is free but the number of trips and amount of fuel required to deliver enough wood to use a wood boiler as our primary heat source would work against us. We have a neighbor who buys logs and cuts and splits them but I haven't asked him how much he pays for a load of logs. I know that many people would consider cutting and splitting firewood too much work but I actually enjoy the work. Slitting wood is good stree relief!

For next winter, we are considering installing an efficient oil burning boiler without removing our 30 year old wood/oil boiler which will need to be cut up with a torch to be removed. We may purchase an EdenPure to heat our upstairs living area and burn wood as it is available during the coldest weeks of the year. Eventually, I would like to remove the old boiler and replace it with a boiler that burns wood and possibly coal.
 
I don't have any detailed information, but I think I have heard of people employing these tankless direct oil water heaters as an alternative to an oil boiler for situations where the heat demand is modest; seems like one of these with panel radiators with individual thermostatic valves for each room, and a new efficient ECM circulator like the Grundfos Alpha could be the cat's meow

http://www.toyotomiusa.com/products/waterheaters/OM-148.php

might be less hassle or even overall less cost than trying to do a boiler+powervent, and it has the advantage of being sealed combustion (it takes air in in addition to expelling the exhaust).

but I don't have any detailed knowledge of feasiblity/ cost of such a set-up- a pro could/ should chime in.

then you could put in some sort of wood unit later.
 
aroth said:
Thank you everyone for the good advice. After discussing various options with my wife, we agreed that the lack of a readily available wood supply would increase the return on investment time on a wood boiler. I should've mentioned in my first post that we are hauling wood from my wife's parents who live 60 miles away. The wood is free but the number of trips and amount of fuel required to deliver enough wood to use a wood boiler as our primary heat source would work against us. We have a neighbor who buys logs and cuts and splits them but I haven't asked him how much he pays for a load of logs. I know that many people would consider cutting and splitting firewood too much work but I actually enjoy the work. Slitting wood is good stree relief!

For next winter, we are considering installing an efficient oil burning boiler without removing our 30 year old wood/oil boiler which will need to be cut up with a torch to be removed. We may purchase an EdenPure to heat our upstairs living area and burn wood as it is available during the coldest weeks of the year. Eventually, I would like to remove the old boiler and replace it with a boiler that burns wood and possibly coal.

Wood availability is definitely a consideration - for what it is worth, the prices vary, but you can probably conservatively figure between $500-1,000 for a load of log-length which is in the neighborhood of about 8 full cords... It is also often possible to "scrounge" a good bit of wood, or make deals with local tree services - but this can be expensive in it's own way. Obviously one also has to figure in the cost of saws, splitter, etc. needed to process the wood...

The efficient oil burner does sound like a reasonable approach, and won't hurt you in the future for doing other fuels if you decide to go in that direction. OTOH, you might want to look a lot more into the question of getting an Edenpure - it's been discussed quite a bit in the Green Room area of the forums here, and elsewhere, with the general conclusion seeming to be that it isn't worth what they are charging for it - a basic oil-filled radiator from Wal-mart or Homer's Depot will do the same job for a lot less money.... At least some of the people posting were saying "scam" or worse about the Edenpure claims...

Gooserider
 
I have Toyotomi OM 148 that I have used for backup when I was heating with my Jotul woodstove.
It is a hot water heater that was tied into my space heating system through a plate hx.
It worked pretty well and is quiet and small. It direct vents.
They are online for about $1500.
It short cycled like crazy since my heat load is so small, but it worked fairly well.
The nozzle wholesale cost is $25!!
And it is a pisser to take apart to clean the tubes.

A better choice is the OM 180, which is a straight ahead boiler. It is still a pisser to clean, but it might not short cycle near as much and
it is designed to go up to 180F (a temp I did not need.)

I now have it tied into my system with a three way zone valve as a backup system in case the tank drops below 105F.
The flow diverts through the Toyo and heats the water for heating.

I have not used it since the tank is always 109F or higher.

If you are not using too much oil for backup (and not having to clean it much) I think the Toyotomi OM 148 or 180 makes sense.
 
I watched the Toyotomi video at http://www.toyotomiusa.com/productVideos.php# . My big question is how does the cost of operation compare to an electric water heater? In other words, if the oil fired water heaters are better than electric water heaters, why don't more people use them? Given the fact that our current heating system only requires hot water, the Toyotomi burners look like a good option. Since we only have moderate heating needs, the sticker price for the Toyotomi is much more attractive than the price for the larger wood or combination boilers. The settings on our current heating system start the water circulation when the water temp. approaches 140 F. We don't need water any hotter than 180 F. Everyone is expecting the price of electricity and oil to go up sharply over the next few years. If I'm spending on a new system, I want to buy the one that will be most cost effective.

Tom in Maine said:
I have Toyotomi OM 148 that I have used for backup when I was heating with my Jotul woodstove.
It is a hot water heater that was tied into my space heating system through a plate hx.
It worked pretty well and is quiet and small. It direct vents.
They are online for about $1500.
It short cycled like crazy since my heat load is so small, but it worked fairly well.
The nozzle wholesale cost is $25!!
And it is a pisser to take apart to clean the tubes.

A better choice is the OM 180, which is a straight ahead boiler. It is still a pisser to clean, but it might not short cycle near as much and
it is designed to go up to 180F (a temp I did not need.)

I now have it tied into my system with a three way zone valve as a backup system in case the tank drops below 105F.
The flow diverts through the Toyo and heats the water for heating.

I have not used it since the tank is always 109F or higher.

If you are not using too much oil for backup (and not having to clean it much) I think the Toyotomi OM 148 or 180 makes sense.
 
It depends on your needs and fuel costs.
If you are only requiring hot water, and your usage is low, put in an electric water heater.

If you are considering backup heat, the Toyo is worth considering.

I would suggest finding out your local energy costs and plugging them into a energy cost calculator like those on
www.builditsolar.com
 
aroth said:
if the oil fired water heaters are better than electric water heaters, why don't more people use them?

Electric water heaters have the lowest up front purchase price compared to other systems, and are also simplest and cheapest to install (no venting needed, can locate them in many places with few constraints, no connections to a boiler as you'd need with an 'indirect' heated by a boiler).

So electric water heaters are appealing to builders, or to people who are building a home and feeling like they're spending boatloads of $$$ on everything else.... so why not buy the less expensive water heater....

If you plan to stay in a house, though (and although the costs of different energy sources will vary by location) the others can definitely pay for the difference in cost, and then start making you money, over time.

Stand alone tank-type hot water heaters (there's one at my place that was here when I bought the house- and was about the only part of the plumbing or heating that was save-able...) tend to be particularly expensive to buy, and have burner heads that need their own annual service, so they only tend to make sense in places without boilers (that could heat an indirect hot water tank), and without natural gas or propane.

During a big chimney replacement and partial new foundation project at my home in the late '90s, I temporarily put in a second hand electric hot water heater that I placed in the yard, out of the way of the "big dig" (rigged a makeshift "roof" over it). My electric Co-Op called me suddenly to make sure that nothing had gone hazardously wrong at my place, as they noticed that my electric use more than doubled. That's how hungry they can be for electricity.
 
pybyr said:
aroth said:
if the oil fired water heaters are better than electric water heaters, why don't more people use them?

Electric water heaters have the lowest up front purchase price...


During a big chimney replacement and partial new foundation project at my home in the late '90s, I temporarily put in a second hand electric hot water heater that I placed in the yard, out of the way of the "big dig" (rigged a makeshift "roof" over it). My electric Co-Op called me suddenly to make sure that nothing had gone hazardously wrong at my place, as they noticed that my electric use more than doubled. That's how hungry they can be for electricity.



They also take FOREVER to recover.

Also, if/when the element(s) need to be replaced, the are usually a bear to get out, if the where in for some time and installed "up side down." Yes, there is an up and down on those higher wattage elements - the closed "U" should be on the top.
 
How about tankless propane. Much easier & cheaper to vent than oil. A lot cheaper to run than electric. In my detached work shop I had a 1 gallon electric water heater for washing hands. It's been off since the fall, tank failure, and, my electric bill has dropped $40 a month for stand by hot water. That's getting replaced with an electric, tankless, hot water.
Some of this equipment might get you a tax rebate or deduction.
 
RobC said:
How about tankless propane. Much easier & cheaper to vent than oil. A lot cheaper to run than electric. In my detached work shop I had a 1 gallon electric water heater for washing hands. It's been off since the fall, tank failure, and, my electric bill has dropped $40 a month for stand by hot water. That's getting replaced with an electric, tankless, hot water.
Some of this equipment might get you a tax rebate or deduction.

Tankless propane or NG heaters are not a bad choice IF you already have the propane / NG installed for other stuff. I doubt they'd be worth putting it in just for a heater... The OP has oil as the existing system, so he needs an oil based solution in all probability...

Gooserider
 
LarryD said:
Aroth,

We are on our second season with an Tarm excel 2200. We haven't had to use the oil "side" of the boiler yet. We haven't need to. I am thrilled with the performance of the wood gasification side. I heat about 4,200 sqft and the 2200 handles that well. For 1,500 sqft the 2000 would work. We didn't have an option for a second flue or power venting. Yes they are spendy, but well worth it.

Good luck

LarryD

Larry,

I'm also looking at the excel 2200, new home, lots of glass, 3700 ft2. Lots of radiant heating, very little baseboard. I'm curious whether you put any heat storage tanks in or you just let the wood cycle with the demand?

Thanks,
meth
 
meth said:
Larry,

I'm also looking at the excel 2200, new home, lots of glass, 3700 ft2. Lots of radiant heating, very little baseboard. I'm curious whether you put any heat storage tanks in or you just let the wood cycle with the demand?

Thanks,
meth

While you CAN run a gasification boiler on a demand basis, you will waste a lot of wood, and make a fair bit of extra smoke and chimney deposits that way, as you will stop gasifying and go back to smoldering every time you lose demand.

It is FAR better to put in enough storage to let the boiler be able to run through a load of wood at maximum output while dumping most of the heat into the storage and minimal heat to the load. That way the boiler works at max efficiency, you make the least pollution, and get the most BTU's of usable heat possible from your wood... It will also give you huge benefits (especially in the shoulder seasons) in not needing to run the boiler as often - just heat up the storage, and let the boiler go out while you live off the stored heat, repeat as the storage cools down...

It's more or less a standing recommendation from all the Hearth folks, as well as a REQUIREMENT or at least a strong recommendation from the boiler makers, that storage be a part of every gasification boiler install...

Gooserider
 
Gooserider said:
meth said:
Larry,

I'm also looking at the excel 2200, new home, lots of glass, 3700 ft2. Lots of radiant heating, very little baseboard. I'm curious whether you put any heat storage tanks in or you just let the wood cycle with the demand?

Thanks,
meth

While you CAN run a gasification boiler on a demand basis, you will waste a lot of wood, and make a fair bit of extra smoke and chimney deposits that way, as you will stop gasifying and go back to smoldering every time you lose demand.

It is FAR better to put in enough storage to let the boiler be able to run through a load of wood at maximum output while dumping most of the heat into the storage and minimal heat to the load. That way the boiler works at max efficiency, you make the least pollution, and get the most BTU's of usable heat possible from your wood... It will also give you huge benefits (especially in the shoulder seasons) in not needing to run the boiler as often - just heat up the storage, and let the boiler go out while you live off the stored heat, repeat as the storage cools down...

It's more or less a standing recommendation from all the Hearth folks, as well as a REQUIREMENT or at least a strong recommendation from the boiler makers, that storage be a part of every gasification boiler install...

Gooserider

Gooserider,

Definately looking into getting the storage put in, just curious more than anything how the excel may have performed without it. Storage is clearly the way to go. Thanks for the reply!

meth
 
DBoon said:
Hi Aroth,

Those with smaller, well-insulated houses are likely to just not see a payback to putting in a good (i.e. gasification) wood-fired boiler. And as you have learned, having a bad one is no savings either given the amount of wood they burn and other downsides. I have a 1250 square foot home that is well-insulated, and would love to go the wood gasification boiler route, and maybe some day I will, but it won't be because I will have a good return on my investment - I just don't burn enough oil to make it cost-effective, even with oil at $4 or $5/gal.

Other options - get a newer fossil-fueled boiler (heresy, I know) that is super efficient, or get a woodstove in your living area. I did the latter for now, and will wait to upgrade the fossil boiler until I really get over my fixation on getting a wood gasification boiler. I

I was looking back over some old posts and realized that I never updated this one. We took advantage of the 30% tax credit of 2010 and installed a Pacific Energy Super 27 in our living room. At that time, the tax credit included installing a stainless steel flue which was pricey, as well as the cement board and tile on the wall and floor. I bought a tri axel of logs and was thankful for the use of a log splitter from a generous neighbor. We enjoyed a warm home during one of the coldest and windiest winters. I replaced a worn out Craftsman chainsaw with a Stihl farm boss and bought a grinding wheel chain sharpener. I have been able to find free wood from another generous neighbor who had two very large trees cut down by the power company and from a friend from work who lives near Blue Knob and wants to clear some trees from their property. Since then, we sold our coal stove, bought another Super 27 and are heating exclusively with wood. We have electric heat as a backup in the basement but rarely use it. I bought another load of logs to stay at least a year ahead. My wife has never been more happy about the temperature of our home. :)
 
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