Hi Umbra,
My fiancée and I bought a house in October. We plan to green the house up as best we can, and one of our first projects will be how we heat the house. Since we didn't have any money after buying, we had to limp through this winter with an oil-powered steam boiler from 1962. Obviously not efficient at all. Plus it was having "puff back" issues so part of the time our basement was filled with lovely oil smoke. What should we do to replace this boiler? I know there is natural gas in the street so we could have the whole system replaced. Or should we look at alternatives such as biofuel and a new oil boiler? Or are there other options that I don't know about?
Jesse
Wayland, Mass.
Dearest Jesse,
Oily boiler toil and trouble, that's what you've got. (If I don't start with a joke they dock my weekly M&M's allowance.)
You look radiant.
Photo: iStockphoto
Let's assume that you'll replace your boiler, although if there is any doubt, call in a technician. Yours is so old that it would be shocking if it were as efficient as modern models. Furnace and boiler efficiency are measured in AFUE (gesundheit): annual fuel utilization efficiency. This is a measurement of how much of the energy is turned into heat, versus how much leaks out or vents off as waste. Modern furnaces and boilers have AFUEs above 80 or even 90 percent; older types often fall below 70 percent. Lord knows what your boiler is, other than a hilarious relic, but others of us who don't have Puff the Dragon in the basement can learn our AFUE either from a label, from a professional, or from learning the combustion efficiency from a professional and then multiplying by 0.85.
I can't find one heating system that is touted as best in all situations, which is logical, since your electricity comes from coal and mine from hydro, your house may have three finished floors and other people have exposed pipes in the basement -- It Depends. The web is here for you, though, and I've picked the U.S. Department of Energy's Energy Efficiency and Renewable Energy site and the government of Ontario for your preliminary decision-making; for lists of the best furnaces/boilers, the American Council for an Energy-Efficient Economy. The EERE and Ontario are thorough, laying out all the choices and assisting you with charts, decision-making tips, contractor assistance, thoughts on fuel costs and environmental impact, and generally overwhelming (but useful) amounts of information. Fuel costs, installation costs, the infrastructure and layout of your home, and various soon-to-be-revealed other limitations will hopefully winnow your choices down until you know which system is best for you.
The simplest thing is probably and obviously to replace the current system with an updated version. Then, if you have biofuel available in your area (which you do), you can look into using that in your boiler instead of heating oil and do a little petroleum sidestepping if it works out. That's a great option if it's available to you. Natural gas burns cleaner than oil (or wood, pellets, or propane), so if the costs and boiler efficiencies work out, changing your fuel source to natural gas might make sense. Other common energy sources include solar, heat pumps, wood or pellet-fueled stoves or furnaces, and electricity. Electricity in your area is probably coal-generated and not so clean.
A drawback to deciding on any system other than a steam boiler is that you'll have to replace the infrastructure that delivers the heat to the "conditioned" spaces. If you switch to a hot-water boiler in order to have hot-water radiators (one reason to make this choice is that hot-water boilers are apparently more efficient than steam), you will have to futz with the radiators if not outright replace them, and you may have to replace the pipes. If you wanted radiant floor heating and your joists aren't exposed underneath, forget it. If you switch to a furnace and a forced-air system, you'll need to install ducting and grates all over the house -- I've learned from EERE that a reason to consider doing this is to have air conditioning as part of your central heating/cooling system.
In sum, yes, there are other options you haven't heard about, and you should look into it because I can't even begin to do the topic justice. Set aside a good chunk of time to do so. When you do purchase a new heating system, be sure it is properly sized for your home. And before you have someone size your furnace or boiler, you want to do all the efficiency improvements, such as insulation, that reduce the BTUs required to heat your home. That's what you want to do. Whether you will have the time and money to do it, who knows?
Flexibly,
Umbra
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Comments
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Sunny Side Up Posted 6:50 am
18 Apr 2007
Don't fret! There are tons of options that are great. And don't hold out: radiant flooring IS a possibility. Let's talk....
But Umbra's summary is right on.
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J26 Posted 7:02 am
18 Apr 2007
Mass Energy Consumers Alliance is a non-profit organization that provides affordable and sustainable heating and electricity options through out the state.
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PBrazelton Posted 7:20 am
18 Apr 2007
As for insulation, windows and doors are a no brainer. Also consider slow rise foam for your exterior walls - imagine having R-30 walls. That's a lot of heat (or cool air) saved.
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crisrich Posted 7:27 am
18 Apr 2007
If you buy a new heat generation system first, it will be oversized in the future, after you insulate your house. Oversized equipment is always less efficient than one sized correctly. So you would overpay twice: for a too large system and for comsumption of energy that is higher than needed (because of the lower efficiency) over the whole lifetime of the new equipment!
As Umbra wrote, the number of options are very large, so it´s best to invest some money hiring a specialized consultant who will make you a complete project, starting with the reduction of demand, which will consist mostly of insulation measures.
You should also ask around and search the Internet for possible financial asssistance and/or subsidies to do a complete energy savings project.
Have fun!
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boogaloo Posted 7:54 am
18 Apr 2007
That is, if I compare the amount of oil I would use in my oil furnace with the amount of oil the utility would use to make enough electricity for my heat pump, the utility will use less.
Incidentally, my preconception was that we could
not drill the wells because of being in the city,
but I was wrong.
I understand the problem that electrical generation can be noxious, but that is a separate battle for all of us to fight with the utility companies and the government.
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eriqa Posted 10:57 am
18 Apr 2007
See: http://tinyurl.com/2m4538
If I were starting from scratch, that's probably what I'd go for.
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Phil Smith Posted 11:57 pm
18 Apr 2007
Any new equipment you get should be of a direct vent design, providing a direct supply of combustion air from the outside into the combustion chamber, and a direct exhaust to the exterior. In both cases two or three inch PVC pipe can be used for venting.
When deciding on upgrading your heating system (You will want to move from the steam boiler as you will not want to tolerate the low efficiency with the peak efficiency available now and in the future being only about 83%) you will need to have the distribution system assessed for possible conversion to hot water.
If you have a single pipe steam system, then it is total replacement time!
Replacement of everything is not always needed. If you have a two pipe steam system then a possible conversion including a reworking of the existing radiators is possible.
You may have to replace the piping and this can be done with pex type piping , the same used for infloor radiant heat. This can be run through the interior of walls to the radiator locations with out as much destruction as one might think.
I like radiators as you can get better zone control with little perks like a radiator for a bathroom that also serves as a towel warmer! You can keep the bathroom cooler with a warm towel to dry with!
A new boiler can also be used to heat your tap water and Solar can be added to this as well.
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Phil Smith Posted 12:03 am
19 Apr 2007
When I say cold, not that mamby pamby stuff of 10 or 15, rather -15 to -30.
Efficiency in the building reducing the need to heat and cool is the BEST investment.
depending on your fuel mix and Location chances are the high efficiency gas heating equipment will end up with a net lower greenhouse gas emissions than a ground source heat pump as well as provide a better return in investment.
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A Siegel Posted 3:55 am
19 Apr 2007
INSULATE! INSULATE!! ... BUT FIRST AIR SEAL!!! Get the house "efficient" in terms of usage as the first step. This is an integrated process.
Re heating ... there are so many options.
If steam/radiant, consider the value of solar hot water as the feedstock. This will lower the energy required to heat up the water to required temperatures for heating. (And, if radiant as a choice and the option is available, dig down a reservoir for storing solar heat from summer for winter purposes.) The solar option thus picks up probably 70+% of the annual hot water heating demand.
Natural Gas: In the Northeast, definitely worth checking out a combined-heat power system. (Such as the Micro-CHP system from Honda / Climate Energy. (http://www.hondanews.com/categories/1048/releases/3822)
If you have an air conditioning requirement (not common in MA), can consider a 'fossil fuel system' combining high-efficiency Heat Pump (mine, SEER 16+) with a high-efficiency gas furnance. With a good controller/thermostat, system switches between the two for the most fuel (and/or cost) efficient option for heating. (And, this creates a mixed gas/electric option for heating.)
Solar passive: Any ability to build back in solar passive heating?
But, to go back, SEAL LEAKS & INSULATE (which, by the way, slow rising foam does both ...) to reduce overall requirements.
Key question for anyone looking to replace a heating system on an old home: Have they had a home energy audit? (A good start is Home Energy Diet (see my review at: http://www.ecotality.com/blog/2007/energy-bookshelf-1-put ... )
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hillhi Posted 5:19 am
19 Apr 2007
That's it--then compare alternatives
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longhsore1 Posted 10:21 pm
19 Apr 2007
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Liara Covert Posted 7:50 pm
21 Apr 2007
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sanjo Posted 10:41 pm
23 Apr 2007
You can turn these panels on and off just like your lights. There are no moving parts, installation costs are minimal, they are 95% effecient (as opposed to the gas burner which is only 84%) and they are comfortable! I am getting ready to do the rest of the house this spring. check out http://sshcinc.com/BarNone2.htm
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reguru Posted 2:10 am
24 Apr 2007
A solar system with an adequately sized storage tank, placed in the basement, could meet not only his heating needs but also provide his domestic hot water (and heat his hot-tub to boot).
If he "backed up" his solar thermal system with a Bosch or Takagi variable flame tankless water heater, which are very efficient, he'd be "greening up" on several fronts AND solving his boiler problem.
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