Oil vs. Natural Gas boiler?

[GayleDC]

I'm a homeowner, not an HVAC pro, with a couple of questions. Thought someone might be able to help me out.

We currently heat our home with an oil boiler. It was originally coal and at some point was converted to oil. I have no idea when, but the house was built in 1932. Anyway, we have received quotes to replace the current oil boiler with a new oil burner, as well as for natural gas. Cost is basically the same for both when you include the cost of removing the above-ground oil tank (in our basement) and lining the chimney, etc.

Our current boiler works just fine and we have it serviced annually. It appears from the paperwork from the most recent service that it runs at 79%, but we are thinking a new one would be more efficient and better for the environment (you know, going "Green" is hip these days).

My questions are:

Should we replace?

Oil or gas?

Any suggestions would be most appreciated. Thanks!

[BaldLoonie]

What's your local cost per gallon of earl and cost per therm of natural gas?

[Freezeking2000]

I would only be installaing a condensing modulating gas boiler if I were in your shoes.

[heatpumpguru]

I agree with the FREEZEKING!! I have never taken out natural gas and installed oil in my 30 years of HVAC!

[beenthere]

As above, what are your gas rates, and what is your oil costing per gallon.

1932 house will be either CI rads, or CI baseboard. Either one will get you good use from a mod/con gas boiler, then you don't need your chmney linered.

[lolson]

i would go with nat. gas
it dont smell

[hedtedjr]

I would have to say that if efficiency and going green are your priorities and natural gas is available in your area, that is the obvious choice. You will have a much better chance of finding an efficient and reasonably priced gas unit than an oil unit.

[tigerdunes]

gayle

get the efficiency of both the oil and gas boiler as well as your cost of oil/gal and nat gas/therm.

use the attached link for fuel comparison calculator.

IMO


http://www.warmair.com/html/fuel_cost_comparisons.htm

[flange]

You really need to understand the system better to make an informed decision, but for the most part a mod-con gas boiler with a reset control scheme should do you more justice. In your climate, you should be able to run your water temps low enough under most conditions to be in a condensing situation. This will give you about 95% efficiency most of the time, as well as good overall comfort. There are a few brands out there capable of doing this, so far I seem to like to Traingle tube the best, along with Viessman. Theeuropean manufacturers have been dealing with high energy costs for much longer than we, so it is my opinion that their technology is superior and proven.

[skippedover]

Gayle, you're going to get as many differing opinions on this as there are responders to your question. Some of the ideas involve solid mathematical calculations. Some involve honest opinions based on experience. If you can sift through them and determine for yourself what suits you, you're a marvel, IMO. Either way, here's my $.02 worth.

Oil and gas are controlled by the same companies. In 35 years of heating service, I've yet to see any significant price advantage of one fuel over the other for more than a year or two. So I always advise my clients to make their decision on something other than current price, unless they have direct communications with the future to see what lies ahead.

You say you've got a converted coal boiler. That connotes large, cast iron radiators and large water pipes. If that's truly the case, you should be sure to get an installing company that knows how to handle big water volume systems. That is, unless you're also replacing the distribution system. Any boiler, be it oil or gas, that can handle low water temperatures is to your advantage. The lower the water temperature used to heat the home at a given outdoor ambient temperature, the less your heating costs will be. If you do have cast iron radiators, you need to know that those are true radiant panels and can produce significant heat at relatively low water temperatures. In that vein, a modulating/condensing gas boiler or condensing oil boiler, all with outdoor temperature reset controls would be the best way to go.

Service is something else again. Getting an installing company that has a stellar reputation for quality service is a must with any modern boiler. With oil boilers, you'll always or should always be getting a combustion efficiency test done with each tune-up. That should be true of gas boilers as well but unfortunately it is not. Relatively few gas boilers are installed and properly set up with combustion analizers. Make sure the installing company does that analysis if you go gas. The gas side of the industry is loaded with mod/con boilers at this time. Life expectancy of the boiler and/or components is something on which the jury is still out. They haven't been in the marketplace long enough to have that data. On the oil side you've got the Buderus and Viessmann who have both had their oil boilers out there for a respectable period of time, particularly in Europe. On the gas side, you've got Viessmann with newer products, Lochinvar Knight mod/con with the highest AFUE, Munchkin, Trinity, Peerless Pinnacle and others.

Finding the right company is the challenge. Everyone wants to sell you a boiler. Not everyone will service it. Not everone has the knowledge to service it. So shop carefully. Educate yourself on-line. Ask a lot of questions and to some extent, cross your fingers. Good luck.

[jackhmr21]

Skippedover, thanks for the detailed info. I see you're from MA too, so I have a question for you.

I have an 1890 victorian and it still has gravity hot water heat. The pipes are as huge as you described. FYI, it is a closed system now (with a compression tank) but it used to be an open system. The oil heat boiler is an ancient cast iron system -- our oil guy estimates at least 50 years. It still chugs along, but the estimate is only 70% efficiency.

The house is fully insulated so we don't get killed with heating bills, but I still think it's time to convert. The similarly ancient oil tank worries the heck out of me.

So, I'm contemplating getting a new system, either oil or gas, and converting to a forced hot water system.

Any words of advice? I found a really helpful Q&A here http://www.oldhouseweb.com/stories/Detailed/830a.shtml but I'm interested in your opinion too. I asked our oil supplier to give me an estimate for a conversion, but I haven't gotten the details yet. I have no idea what he's going to propose, but I want to be armed with lots of info.

Thanks!

[inhoth2o]

condensing high efficiency gas is the way to go a little more $ but they mosty all have out door reset, as said they do need that low return temp to get that efficiency, condensing oil reaily won't be here til low sulfur fuel oil comes, til then you get mad at your gas compamy to bad, oil you call someone else

[twisterbret]

Home owner here

I might kicked kicked a bit but I converted from Oil to Nat Gas in Dec and I saved 2000.00 on fuel alone. I also saved on 200.00 for my oil repair contract. My payback is 2 to 3 years. Your payback my diff. We never hear our 94.1 AFUE Bryant Evolution.

[beenthere]

Home owner here

I might kicked kicked a bit but I converted from Oil to Nat Gas in Dec and I saved 2000.00 on fuel alone. I also saved on 200.00 for my oil repair contract. My payback is 2 to 3 years. Your payback my diff. We never hear our 94.1 AFUE Bryant Evolution.

Just curious.
How old was yoour oil furnace?

[twisterbret]

Just curious.
How old was your oil furnace?

It was around 12 years old. 80% Ducane. It was tuned up each year and ran very well. I figured out my savings my just added of what it would cost to fill my oil tank.
I got a .35 per gallon discount via buyers group. That put in the price at around 3.00 gallon and by Jan even higher.
3.00 x 275 Gallons is 825.00 and 1000.00 Feb.
3 fill ups per winter/early spring 3000.00
My gas bills have been
119.00 Dec
195.00 Jan
125.00 Feb
New bill should get here soon.

This past winter has been pretty mild and I'm basing my 3 tanks on harsher winter weather. So say 2 fill ups.
2000.00 VS 439.00 plus this coming bill 120.00

2000.00 vs 559.00

We've also been keeping our stat at 71 with no setback. With oil we had it at 70 with a 68 setback at night.

The switch worked out for us. Our local gas company was offering 3 year interest free loans.

[beenthere]

Cool.
Thanks for the info.

[da_poppa]

I asked this question on another site a few months ago and no one had an answer. Thought I'd try here. What is the life expectancy of a mod/con boiler? any differences between aluminum and stainless? Any local issues with condensate disposal?

[beenthere]

They haven't been aroound long enough to know the average life expectancy.
Many SS ones have 10, or 12 years warranty on the HX. Some Aluminum ones have 15 years warranty on the HX.
I prefer the Weil McLain Ultra, aluminum block.

[CurtisALCH]

Niether oil or gas, go electric with this very disruptive technology. The Acadia Combined Heating and Cooling System. www.gotohallowell.com and it works down to -30 degrees. I saved over 60% in oil cost this winter alone! It's awesome and I would tell anyone and everyone to check this out. Good luck.

[beenthere]

They may catch on.
Let us know how it holds up over the next 5 years.