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Recommendations for a new boiler


I am a first time home buyer that purchased a house that was built in the 1920's (in central NJ) that has a Weil Mclein gas-fired steam boiler from the early 90's that appears to be cracked and will need to be replaced. The BTU rating on the unit is 175,000 (input) and 142,00 (output). The house is roughly 1,400 Sq. Feet. I have looked at several websites that allow you to calculate the BTU's required based on the square footage and location of the house. The results that I get estimate that I need roughly 66,000 BTUs for my house.

Now that it is time to replace the boiler I am wondering if I should replace it with a comparable size to what I already have or would it be a better idea to go with something smaller and more in-line with the recommendation I got from the calculator? (some notes on the house: it was built in 1927 and retains most of the original plaster and has not been insulated with the exception of the bathrooms and kitchen that were recently remodeled. I am not sure if the lack of insulation allows for more heat-loss which could possibly explain the higher than normal BTU boiler)

Also I have priced out a few different brands but am not really sure which is a good choice to go with. I have looked at Weil Mclain (which is what I have and appears to be more expensive), also Williamson, Slant Fin and Burnham.

Any information or recommendations would be greatly appreciated. Thank you in advance!

Re: Recommendations for a new boiler

I think 66K BTU will be insufficient. Are you sure about your calculations?

A good idea is to start calling plumbers/air conditioning guys for estimates. Act fast, their schedules are getting full this time of year.

Re: Recommendations for a new boiler

bigel 6,

I agree with dj1----look in the Yellow Pages under Heating Contractors and get at least 1 or 2 techs in there ASAP to give you a solid evaluation of exactly whether you have a broken boiler or something that can last another winter---make as many calls as you have to---techs are very busy this time of year doing routine boiler cleanings for all their customers---you should think seriously of following the recommendation of the tech(s) you call in as to if the present boiler can last another winter or needs immediate replacement---hopefully it can wait until the spring if you need a replacement (a replacement takes time & the heating techs are very busy now, but you may be able to find one that can do it)----I would strongly consider a replacement that would remove the steam system & install a forced hot water boiler, perhaps using the existing radiators, if they can be used for forced hot water (hydronic); otherwise, hot water baseboard heat can be used, or even forced hot air, if the estimate is lower; as you've perhaps already found out, steam boilers require constant daily maintenance (dirty water blowdown, for example), and it's much harder to get reliable steam heat with all rads functioning, headaches you wouldn't have with forced hot water or forced hot air---the fact that you have natural gas on site is a big plus for the house, but you will also have to address the serious lack of insulation inside the exterior walls---this can be easily remedied by having insulation techs blow in fiberglass or cellulose in the 4 inch/6 inch exterior wall cavities---they remove a small piece of exterior outer siding, drill a small hole & inject the insulation to create a whole-house blanket that keeps the winter heat in and the summer heat out----an insulation job pays for itself in less than a year with reduced heating & cooling bills, not to mention having a much more comfortable house---and the savings $$$ keep coming year after year!

Try to find several other HEAT LOSS CALCULATORS on-line (Google heat loss calculator); an acceptable heat loss for a 1400 sq ft well-insulated house with double-pane storm windows would be between 25 to 35 btu per sq. ft.--that would give you no more than 44,800 btu/hr heat loss that the boiler would have to replace in winter per hour (1400 sq.ft. X 35=44,800 btu/hr); compare THAT with a loose-fitting house with zero exterior wall insulation & perhaps no double-pane windows & the heat loss is probably 100 btu/sq.ft. or well over 100,000 btu/hr---that's gas heating bills that are flying right thru the loose walls & windows to the great outdoors---there's no need for it!

You're really spending a lot of money on gas bills with a steam boiler that has a heat input of 175K and an output of 142k--this boiler is probably way oversized, & is burning way too much gas---with much of the heat going up the chimney as waste energy (if the present boiler is rated at less than 75% efficiency) to heat the great outdoors.

The "higher than normal input/output boiler" was therefore previously put in because the installer will put in 1) a larger than needed boiler "just to be safe", regardless of how much gas it burns, and 2) because there is no exterior insulation & storm windows present to hold the heat in the house.

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