how long will old boiler last?

[Tom]

Here's my question stated simply: How long do boilers generally last? I'm trying to determine if the one in my home will last through this coming heating season. Is there any way to check besides looking for leaks?

Here are the details: I've got a Utica oil-fired boiler with radiators, in a single family home. It's a Utica O.U. Series. I'd guess the boiler is roughly 35 years old. The burner on it was replaced, I think in 1995. The boiler also has copper tubes running inside it to heat the home's hot water.

When a boiler fails, does it usually fail suddenly or can I limp through a season with a small leak by simply refilling the water? It doesn't seem to leak now, judging by the water level in the glass tube. I have to manually operate a valve to add water, so I'd know if the water level was noticeably declining.

What happens with a sudden big leak? Does the burner then just not come on because of some overheat-sensor?

If it does develop a leak, can a leak be plugged?

There's one other consideration: I had it shut down from May to December of

2008. When I started it back up, all seemed fine but later I noticed a rust colored stain on the concrete floor. I believe that happened because of the sudden change in temperature. There has not been a single drop of visible leakage since that one time. When I do empty the low water shutoff every other week or so, the water that comes out is never is rusty. It is either black if the boiler's been run a lot, or else it's pretty clear otherwise.

So, what should I do to try and figure if it will be good through this winter, in PA? Thanks.

[Mikepier]

Sounds like you have a steam boiler which is more forgiving with leaks as opposed to a hot water baseboard boiler which is always under

10-15 PSI of water pressure from the regulator. Generally if you have a leak below the water line, you'll know because you'll see water on the floor. And if the leak is above the water line, you'll see steam leaking out, and thus the boiler can never get up to pressure.

I have seen boiler last 50 years, and I had a steam boiler that only lasted 15 years. Just turn it on and see if the pipes get hot and check for leaks. If everything checks out, your good to go

[salty]

I'd say that at 35 years, you are well beyond the normal service life. Utica makes good boilers, but 35 years is a long time for a residential boiler.

[Pete C.]

I wouldn't agree with that at all.

Oil fired boilers tend to be notably more durable than most gas fired boilers. The wear items on a boiler are the burner, the circulator pump and the firebox / chamber. The bulk of the boiler should last pretty much indefinitely unless there is a real problem such as an unrepaired leak leading to constant refilling with hard water.

Since the burner was replaced recently, it is unlikely there is anything really wrong with the unit and no reason to believe it is in imminent need of replacement. A newer oil fired boiler will be a bit higher efficiency, but not a lot higher if the current unit has a newer burner and is in good tune.

A normal seasonal tune-up and inspection by a reputable service company will tell you how the boiler is doing in terms of efficiency and should not any potential problem spots. The water you saw was most likely a little overflow purge from a full boiler of cold water heating up and expanding, a very normal occurrence.

[HeyBub]

It'll probably be okay.

The steamboat S.S. Sultana, during it's life, had multiple leaks in its boilers. They were patched with iron plating and bolted in place. The Sultana continued serving commerce on the river with little interruption.

Until three of its boilers blew up, killing an estimated 1,800 returning Civil War Union Soldiers and sinking near Memphis.

[Vic Smith]

No way to check unless you're a chimney shaker. If you are you, see how hard it is to drill a hole in it. Not something I'd worry about. Worse thing that can happen is you have to buy a kerosene heater or 2 until you get a new one in.

Hot water boilers last a looong time. My ma replaced one because she went from coal to oil. It was maybe 50 years old. I replaced that one for her when it was 20 years old to go to NG.

The one in my old house is still working and is probably 60 years old. If the water is dosed with a rust inhibitor and the fire sides are cleaned once in a while cast iron lasts a long time.

The water heater part I don't know about. And I'm assuming you're talking about a boiler with cast iron water jacket, which is the only kind I've had.

Hot water boilers are normally replaced to put something more efficient in, not because they leak.

--Vic

[ransley]

For just boiler pros post at

I have a 55yr old Kewanee that is now looking shot, but it has been flooded in summer many times. Old Kewanee commercial boilers were made to be repaired but I have no idea on the construction of your unit. If its hot water heat you might save 20-35% on a new condensing boiler, if its steam savings will be less but you could sav e 20% easily, so energy savings should be something you should look into, not just how long will it last.

[RBM]

The only thing on it with moving parts is the burner, and you've replaced that. It's 35 years old, no autofill, probably no low water cutoff, it's really unlikely to suddenly have a catastrophic crack. I certainly wouldn't lose sleep over it.

>

[Ed Pawlowski]

Here's my question stated simply: How long do boilers generally last? I'm trying to determine if the one in my home will last through this coming heating season. Is there any way to check besides looking for leaks?

Here are the details: I've got a Utica oil-fired boiler with radiators, in a single family home. It's a Utica O.U. Series. I'd guess the boiler is roughly 35 years old. The burner on it was replaced, I think in 1995. The boiler also has copper tubes running inside it to heat the home's hot water.

************************************************************

Utica was one of the better, but they all fail in time. I replaced min at

30 years, a friends replaced theirs at 29 years. From talking to a couple of installers, that is a common time for them to start to fail. That said, I know a few that are over 50 years.

The copper coil for hot water will also plug in time too. They are fairly expensive to replace ($450 to $700) and they are not the best way to heat water. When operating properly, they make a lot of hot water fast, but they also lose heat and run far too often just to keep a reservoir hot and ready for use. How often do you hear the boiler start up when not heating? All that oil is wasted. Many boilers today use heat exchangers with indirect tanks.

Since you have a sight glass, I'm guessing you may have a steam boiler. Steam has many advantages, but not often used in residential service. If this is new to you, be sure to find out how to operate it it properly.

Boilers can often be repaired, but the cost may be high. The burner m ay be better than the original, but still not as efficient as the newest ones. In my case, the house was build in 1978 and I put in a new boiler almost two years ago, a System 2000 by Energy Kinetics. With the state rebate, the federal tax credit and the savings for oil (38%) it is paying for itself just with oil savings. It may be worth looking into the real cost of buying new and having better, reliable heat.

[Pete C.]

It's the common tankless DHW coil inside the boiler jacket. When those die, typically due to hard water deposits and corrosion in them, you either replace them if the part is available or switch to an indirect fired DHW tank setup.

Yes, and if it is a good quality boiler and already had a burner replacement in 1995 it's going to be running pretty close to the efficiency of a new until already if it's in proper tune.

[salty]

Take it up with the manufacturers, then. I think they know a little more than you do about the AVERAGE service life of the products they build.

[salty]

As wasteful as it sounds, an oil fired water heater coil is still far cheaper to operate than a free standing electric water heater.

[Pete C.]

The manufacturers want to sell boilers, not give customers the maximum service life. If you're paranoid you can replace your boiler every year if you want, or you could be sane and do an actual evaluation of the unit to see if it actually has any issues.

[salty]

The manufacturers don't maintain statistics on average boiler service life just to sell boilers. In any event, it is a statistic, based on historical records, and not an arbitrary number.

We know the statistical average life of humans, too.

[Tom]

[snipped]

First off, thanks to everybody for all the great replies. I'll probably see if I make it through this season and then maybe switch to a gas boiler next year. Yes, it is steam heat here.

I'm getting frazzled looking at pages for "indirect DHW setup" quoted above, even this brochure:

nobody explains what exactly it is. It's apparently a separate tank, rather than having the coils right in the boiler primary water - but where does it go? How does it attach to or connect with the boiler?

Thanks again, I learned a lot.

[Pete C.]

Based on warranty claims and parts sales, which really don't tell the full picture.

[Pete C.]

Indirect fired DHW tanks are separate highly insulated hot water tanks, much like a standalone water heater. Instead of having a burner or electric heater, they have a heat exchanger coil which is plumbed into the existing boiler like an additional zone. They work quite well, but the tankless DHW coils are common, cheaper and also work pretty well.

If you are looking to replace the boiler, be sure to do an accurate comparison of your options. Don't fall for the common ploy of comparing a new gas boiler to an obsolete oil boiler. Compare apples to apples, i.e. a new gas boiler of a given quality level to a new oil boiler of a given quality level. Also include in your comparison items such as monthly service charges for gas service, annual maintenance costs, etc. along with the cost per BTU for each fuel.

If you're looking at a system replacement you should also look at the big picture and include in your comparison a change to a heat pump (air or ground source as appropriate) which would give you both heating and cooling. Installing ductwork is an added expense, but there are some decent options there depending on the structure, and in replacing a boiler you might well switch to hydronic instead of steam which would entail replacing radiators.

You certainly don't appear to have any time pressure, so you have plenty of time to research the options and if you decide to make a change, make it during the cheaper off season.

[salty]

bzzzt!

[Pete C.]

How many people do you think report to the OEM that their long out of warranty boiler had failed, was not economically repairable and was being replaced? The answer is close to zero, therefore the OEM has very little information on the true field longevity of their equipment.

[salty]

Oddly enough, the people who sell, service and install boilers have a lot of contact with the manufacturers. They sometimes talk about something other than the weather.

DOH!