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Oil-natural gas conversion. Boiler and water heater question

My Colonial is roughly 3000 sf, two full baths with no fancy hot tubs or shower systems. I have baseboard, hot water heat. Four differant plumbers gave four widely differant quotes on four differant units. Some units they've recommended are: Buderas condensing 95% efficient, Burnham 82%, Munchkin 95% and a Weil-McClain unit. Some say the European wall hung units are most economical and enviromentally sound while others say the traditonal units, while less efficient, provide a better burn and require less time and effort to work thus burning less fuel. European wall hung units, I'm told, are best suited towards radiant applications while the "traditional" burners work best with baseboards. All agree that a water storage tank is the best way to go, but all have their favorite manufacturer. What are the facts? What units are reliable? With a car purchase, there are many resources for information. For this type of work, I've found very little. HELP! Thanks!

Re: Oil-natural gas conversion. Boiler and water heater question


You didn't mention your location, or if you have done a fuel cost comparison for your area, or if you need any insulation in your exterior walls or attic---this should be done first before you order a new boiler.

Did the plumbers you consulted so far do a HEAT LOSS CALCULATION to determine how many btu/hr boiler you need???---many boilers installed these days are too big & thus waste fuel.

Hot water heating with an indirect hot water heater is the best way to go---with fuel oil reaching historically high levels, a lot of homeowners are converting from oil to natural gas, if it's available in their area.

It's quite common to get wide variations in quotes from heating contractors & oil dealers on choice of boilers---------there's so much equipment out there & contractors tend to recommend what works for their area, but also perhaps because the wholesale boiler distributors in a given area carry only a certain number of brands and the competition is fierce.

The boilers you mentioned all have a good reputation---Buderus is German and well-regarded--Burnham, Munchkin, Weil-McLain & the others are good U.S. mfgrs.

I've always recommended Triangle Tube, Viessmann, Buderus, Peerless, Dunkirk, NTI Trinity, Crown---Viessmann is also German, well regarded, but expensive.

Yes, you are right, the newer generation of boilers are usually condensating, wall-hung, made of stainless steel (rather than the traditional cast iron)---I prefer a roof vent, rather than a side-wall vent to avoid any noise or fumes at a lower level---I would avoid condensing boilers with an aluminum combustion chamber--especially if you have hard water---they don't hold up as well as a stainless steel unit.

The less-expensive line of boilers made of cast iron have an 85% efficiency, instead of a 95% efficiency, but cast iron is a tried & true design & the equipment tends to be much less expensive, simpler in design, easier to service with less breakdowns & 10% efficiency, though significant, is not a deal-breaker---if you intend to move in a year or two a less expensive cast iron system may make more sense, instead of plunking down $10k for a top of the line condensing/variable output boiler.

There's some truth to the idea that the condensing boilers are more appropos to radiant heat---baseboard is designed to operate at water temps of 180 degrees--so make sure you get a boiler that operates at that temperature---sometimes more baseboard is added to the house & the boiler is allowed to operate at lower temps---this saves fuel but means a higher cost in more baseboard installation.

Don't ignore getting quotes for a new system from fuel oil dealers in your area---they are also licensed to install gas equipment & often will give you a better quote.

The links to two articles I've written (below) previously will give you some background on quality boilers & other resources.

Furnace Compare reviews the different mfgrs & their warranty statements; energy star. gov has a list of all the most energy efficient boilers (AFUE of 95%); the other links allow you to do your own heat loss calculation & fuel cost comparison.

Fuel cost comparisons compare the dollar cost of 100,000 btu of oil heat with the dollar cost of 100,000 btu of natural gas heat---make sure you do this before you convert--you don't want to convert only to find that fuel oil will actually cost you less in your area, despite its price spikes.


Re: Oil-natural gas conversion. Boiler and water heater question

Thanks Jack!
I live on Long Island, New York and am doing some renovation work at the house so the insulation will be upgraded as you've suggested.

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