After last year's budget busting oil bill for my 44 year old hot water boiler, it's time for an upgrade. House is 2150 sqft. DHW is supplied by an electric tank. We also have gas service to the house.

Before this year, oil and gas were fairly equal cost-wise. Now with oil at 4.00+/gal., oil costs almost twice as much as gas per 100,000 BTUs. But will gas eventually catch up with oil?

My options are:
87% efficiency oil boiler
83% efficiency gas boiler
95% efficiency condensing gas boiler (with some venting issues)

If I go with the 83% efficiency gas, I need to line the chimney, and with either gas system, the oil tank in the basement with $700 worth of oil in it will have to be removed at some cost. I hate these kinds of decisions.

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1985 380SE Blue/Blue - 230,000 miles
2012 Subaru Forester 5-speed
2005 Toyota Sienna
2004 Chrysler Sebring convertible
1999 Toyota Tacoma

I can't tell much without knowing the unit costs in your location. Around here natural gas always wins in cost per btu compared to electricity and oil.

If your oil fired boiler is in good operating condition there may be no reason to remove it. You can probably without too much trouble leave it in place and intall the new gas fired boiler beside it. Probably a heat exchanger to boost your electric hot water heater would make sense too.

I would go with the 93% effecueint unit and either save the oil for future use or burn it in my diesel car or truck.

Good luck.

Tom W

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

I just recently went through this myself. I don't have gas in my house but could have it run from the street.

I ended up upgrading the burner on my 60+ year old Dynatherm (it has a 36" heater coil). It reduced my oil consumption but I still have to deal with the oil prices. I'm getting a fireplace insert and will be burning wood this winter.

My heating bill for oil last winter (excluding DHW) was $3600 and I can get corded would delivered for the same heating ability for $700-$900. It will be more work, but the savings are worth it.

I also plan to install a solar preheater to lighten the load on the burner. I may end up getting an electric water heater and use the preheat just for that.

After the upgrade to my heater was complete, the tech showed me how carbon build up had my heater running at less than 50% efficiency.

With the new burner and a new delay that gives a 5 second flue priming before the burner fires, I am running at at least 87% efficiency and the carbon won't build up nearly as fast.

I'm in the process of adjusting the boiler temp so I can have it as low as it can be and still offer comfortable hot water and heat. So my efficiency has the potential to be even better.


I'm interested in knowing what you end up going with so I'll be following this thread. Good luck.

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Chad
2006 Nissan Pathfinder LE
1998 Acura 3.0 CL
OBK#44
"Pleasure in the job puts perfection in the work." - Aristotle (384-322 B.C.)

SOLD
1985 300TD - Red Dragon
1986 300SDL - Coda
1991 - 300TE
1995 - E320
1985 300CD - Gladys

Gas is about $1.70 per therm. Oil is $4.00 per 139,000 BTU.

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1985 380SE Blue/Blue - 230,000 miles
2012 Subaru Forester 5-speed
2005 Toyota Sienna
2004 Chrysler Sebring convertible
1999 Toyota Tacoma

Electricity is the only way to go where I live. Gas and LP is only used for cooking, for those who prefer it.

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1999 Toyota Corolla VE (Mine)
2006 Honda Odyssey (Wife's)
1979 300CD (sold)

My girlfriend can heat homes....she's pretty HOT

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1981 300 SD 213k miles "Stock for now"
1999 Super Duty 7.3L 113k miles
1981 300 SD 180k miles "Heavily modified" SOLD

Send her over.

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1985 380SE Blue/Blue - 230,000 miles
2012 Subaru Forester 5-speed
2005 Toyota Sienna
2004 Chrysler Sebring convertible
1999 Toyota Tacoma

I'm in your exact situation and am pondering your exact scenario.

I'd like to take a look at the 90% condensing gas boilers. I don't think any of them approach 95%. I did install one of them in a rental house with hot air and it did an excellent job.

If you find any good one's please advise or post on the thread. With oil at about 2X the cost of gas, there really isn't much of an option..........have to make the switch. Shouldn't cost more than $2K...........plus another $500. for a hot water heater.

She probably would... she grew up in Rockville.

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1981 300 SD 213k miles "Stock for now"
1999 Super Duty 7.3L 113k miles
1981 300 SD 180k miles "Heavily modified" SOLD

Then she can bring her sister too - double the BTUs!

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1985 380SE Blue/Blue - 230,000 miles
2012 Subaru Forester 5-speed
2005 Toyota Sienna
2004 Chrysler Sebring convertible
1999 Toyota Tacoma

I worked out a spread sheet and none of the options pay for themselves until 3-5 years down the road. I figured in oil prices climbing from $4 to $5, and gas increasing by 20% each year. The most expensive after 3 years is still the condensing gas boiler. In my case I have to consider the $700 loss of the oil in the tank (you can barely give the stuff away around here) and $1500 to have the tank cut up, cleaned, and removed. I liked the idea of keeping both oil and gas systems, but I don't have the room.

The cheapest solution is switching to a retention flame burner on the existing boiler. I might even be able to do this myself. Next cheapest overall is the regular 83% efficiency gas boiler. As a rule, you pay a steep price up front for the best efficiency. Of course my calculations could all mean squat if fuel prices go on another wild roller coaster ride.

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1985 380SE Blue/Blue - 230,000 miles
2012 Subaru Forester 5-speed
2005 Toyota Sienna
2004 Chrysler Sebring convertible
1999 Toyota Tacoma

I haven't priced them out yet.

But, I did get a 90% efficiency gas hot air furnace from an e-bay seller for $700. This was a 60K BTU unit for a small rental house. It was a brand new Goodman and worked perfectly.

The cost of the unit is usually a fraction of the "total price" that you get from a contractor. So, I'll probably do it myself...........as usual.

If I can get the boiler for $2K, it will pay for itself in just over one heating season at current gas prices.

I have gas H/HW already but the furnace is easily pushing 40 and the HWH is from the early 80's so there is definitely room for improvement (once funds permit).

Are those combination HHW units a good option? Or is it like many multi-task items that do both things but neither particularly well? I like the idea of downsizing to a single unit as long as the efficiency is still there. I haven't looked into any pricing yet as it's not something I can tackle yet financially.

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1980 300TD-China Blue/Blue MBTex-2nd Owner, 107K (Alt Blau) OBK #15
'06 Chevy Tahoe Z71 (for the wife & 4 kids, current mule) '03 Honda Odyssey (son #1's ride, reluctantly) '99 GMC Suburban (255K+ miles, semi-retired mule) 21' SeaRay Seville (summer escape pod)

I just called my oil company and oil is now at $4.76. I will have to rework these numbers for sure.

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1985 380SE Blue/Blue - 230,000 miles
2012 Subaru Forester 5-speed
2005 Toyota Sienna
2004 Chrysler Sebring convertible
1999 Toyota Tacoma

Just adding my 2 cents

I am not sure what to do about your furnace, but I know that one of the best bangs for your buck is having extra fiberglass insulation blow into your attic. Not sure if your house has an attic. I am going to have it done this year. It is quick and not very messy. It especially makes sense as fuel prices rise.