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Replacing 25y old furnace

I have noticed there is a similar thread, but the situation is different enough for a new thread.

I have an old house (90y) with an old furnace (22y?) that is connected to hot water heating system. I was recommended to repair a few things (boiler valve (all three) and bleeding valve) that runs ~$1300, and suggested to consider total replacement.
The cost or buying and replacing (there is no way I can DIM) depends on efficiency of the furnace, and 80%: ~$7300, 83%: ~$7900, 90%: $12000, 95%: $17000 (and $1500 return).

I am looking into staying for 5y or so, and the heating cost is low because I don't spend time at home (~$500 at most). If the energy efficiency of the current furnace is ~65%, I would save 75$ each year. If I just repair what I have, it would cost me $1300+$150x5 (maintenance fee)=$2000, so even buying the least energy efficient one does not make a lots of sense to me.
(Plus I secretly think keeping old car or old furnace to the end of the life is greener than buying a shiny new one...)

BUT: I am not taking into account additional maintenance fee that could be needed in future, and an old furnace could hurt the selling price of the house when the time come.

Any suggestions? Opinions? Experience?

I also like to know if the quote I was given is reasonable one.

Thanks everyone!

Re: Replacing 25y old furnace

Hard to tell from here what's best to do in this situation---did you have trouble with the boiler this past winter---do you live in a cold area, or moderate locality.

You can't be using it all that much if you spent only $500 past heating season.

Is it oil-fired or gas-fired--what are the "valves" mentioned---are they zone valves??? Do you mean a bleeder valve on the radiators, or on the boiler???

How about the total square footage of the house---is it well-insulated, are the windows in good shape????

If you've had problems with the unit in recent heating seasons & it seems on its last legs, try getting additional quotes---consult the Yellow Pages under "Heating Contractors" & get several opinions about the condition of the boiler.

A 25 year old unit is probably on its last legs & even a reliable standard, every day boiler at 83% AFUE can be had for $1500 plus installation---that's why it's important to get as many quotes as you can, if you've decided to replace it.

Any photos would be helpful.


Re: Replacing 25y old furnace

Sorry for non-descriptive thread.

I live in Nothern OH and it does get cold in winter. The house is two-story 90y brick house and the walls are not insulated. I have done basics such as weather-stripping and insulating attic (to R-60) but still have single pane steel windows (replacing will cost >15000 so I am not looking into those). It is ~1500sq without basement, ~1800sq with basement.

I did not have any problems with my furnace this past winter. It is gas furnace. I called in the tech person for basic maintenance, and according to him, the heating system (hot water) has a lots of air in (I could hear sizzling sound) and is inefficient. That is because the valve (it is not for zoning, it is used to fill/relief and possibly drain in spring and refill before winter) and bleeder (attached to the expansion tank) is clogged. Replacing them costs ~$1300.

The heating bill for me is low because I don't spend much at home and keep the temperature just enough so that the pipes do not freeze. I am ok with my life style.

Is 80% unit only cost $1500? Could installation cost $5000? I plan to look around a few more quotes, but ball-park idea of overall cost would be helpful. In the past thread, I saw # like $3700-$6000, but that was two years ago.

Re: Replacing 25y old furnace


Getting a specific quote on a boiler replacement (you have a boiler there, not a furnace) is difficult for various reasons, but for an average boiler plus installation costs you can expect to pay anywhere from $3500 to $10,000.

When you get bids from installers, tell them you are out of work & money is very tight at the moment, & that you want the lowest quote they can manage to give.

What drives the $$$ quote up is the added components.

Newer boilers, for example have a flue exhaust of <300 degrees, as opposed to older boilers which have an exhaust of ~600 degrees---this often means a stainless steel chimney insert has to be installed to get an adequate draft, because masonry chimneys are much harder to heat for draft purposes---sometimes a forced air draft inducer has to be attached to get the exhaust up the chimney---both these items are quite expensive---a double-wall stainless steel chimney (big bucks) may have to be used instead of a brick/masonry chimney.

But if you can use your present chimney without any add-ons the installation should be much less expensive.

Home Depot in northern states sells Slant/Fin boilers for $1500---consult the Yellow Pages under "Heating Equipment" for heating supply houses--some of them will give a quote for various boiler models--there are sites on the net like www.patriot-supply.com and www.pexsupply.com that carry a limited number of boilers, and give quotes---also Google boiler supply chains like R E Michel, Sid Harveys,Pameco,& Simon's Supply for online websites.

You may be able to get a better price on the needed repairs you mentioned---the dual valve (pressure relief/pressure reducing) sells for ~$60 & the valve for the expansion tank should be half that---this stuff is not rocket science; if there is a friend or relative that can do some of this it will cost lots less---see if any of the "handy man" people that advertise in your area do heating work.

It sounds like you have a conventional steel expansion tank attached to the joists above the boiler---these are often replaced with an Extrol Model 30 ($40) bladder-type expansion tank that have much less problems with air getting in.

Boiler systems should rarely, if ever be drained/refilled---this introduces additional air (entrained in the new water) that separates & has to be bled out----bleed the system by opening the bleed valves on the radiators/baseboard that are highest in the system.

If the expansion tank (older type) gets "waterlogged", it DOES have to be drained.

Try to do something about the wall insulation---brick walls sometimes have cavities where an insulation co. can blow in cellulose insulation for a few hundred $$$ for the whole house---this is money well spent---also try to get some 2nd hand storm windows you can install for the winter months---this would mean a big drop in your fuel & cooling bills.

Google "boilers product list" to get a list of hundreds of energy star boilers with their model numbers so you can check their prices--- download the XLS version of the 3/26/10 version of the list, or "view as HTML" version---you can then Google specific model numbers of the brand names listed below--figure you need approx 70k btu/hr size cast iron boiler; thus a gas-fired Slant/Fin Victory or Peerless PSC can be Googled for an online price check.

I favor affordable boilers by Crown,Dunkirk,New Yorker,Peerless, Slant/fin, Utica,Biasi,Smith.

Many heating issues, components,info & repairs are covered at www.inspect-ny.com/heat

Click onto "heat" on their main page.

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