Steam Boiler Early Failures

heatman

Just had my third Burnham IN9 steam boiler fail due to premature corrosion. First one lasted about 9 years, but I owned the house for only 2 of those years. The second one lasted about 4 years. This third one lasted 11 years.

The system has no obvious leaks, properly functioning vents, no buried wet returns, no additives, no surging, and piping that multiple experts have told me is fine. When the third boiler was installed, a VXT water meter was added to monitor makeup water. The VXT adds water (2 gallons) roughly once a week in the winter if it is cold, less frequently if not so cold (Boston area). For reference, the IN9 is a 13.5 gallon boiler with 10.5 gallons of steamable water. The makeup water comes from town supplied water with the following analysis:

pH - 7.0-7.5
hardness - 80 ppm
total dissolved solids: 350 ppm
chlorides - 140 ppm
sodium - 50 ppm
sulfate - 12 ppm
calcium - 20 ppm

This is getting expensive. And no the boiler warranty did not do me any good. It only covered the heat exchanger cost, but the repair cost to replace the heat exchanger was so high that it cost only slightly more to buy a whole new boiler and install it. It’s kind of like having no warranty at all.

Just a comment here. I’m an engineer. Usually when you design something, you over design so that there is a margin of safety. These boilers seem a little too fragile to me. I see many discussions where the install or maintenance is blamed for boiler failures. Although it may be true that an excellent installation and excellent maintenance would provide long boiler life, should the boiler designers be counting on that? I have never counted on such things for any products that I designed. That would be way too optimistic. Just a casual reading of various web sites to see how often these steam boilers corrode to the point of failure should convince them otherwise. It is not so unusual for steam systems to leak some water. It is not so unusual for chloride to be present in the water supply. My opinion is that the design should take these as a given and still function for 15-20 years. These should not be used as valid excuses for failure.

SWEI

304 stainless is generally specified to handle up to 100 PPM of chlorides. Above that we specify 316.

2 gallons per week is a lot of makeup water. I suspect that and the chlorides did the job.

KC_Jones

2 gallons per week is MASSIVELY excessive. You have a real problem somewhere. Burnham states in their manual you shouldn't use more than 3 gallons per YEAR. You have a system problem somewhere and you should seriously find it. Metal corrodes, you can't "design" that out.

BobC

Are you on MWRA water? Ive attached the MWRA report from about a year ago, chlorides are listed on the last page.

Some areas between Boston and Providence are known for having high chlorides and it sounds like you are in one of those areas. The water use is high, I assume this does not include water added to refill after blowing the boiler down?

Bob

Steamhead

My solution would be a Peerless 63-06. Or, for slightly better efficiency, a Slant/Fin TR-50H with a Carlin power gas burner.

New England SteamWorks

One hates to cast aspersions, and it could be as simple as Burnham sells more boilers than anyone else (no idea if that is true), -but the reports and our own instances of Burnhams failing are nothing less than alarming. I've read their chloride report and my first thought was: If it's the chlorides, why don't other boiler manufactures report the same/suffer the same?

As a company, with the exception of the world-renowned MegaSteam, we have abandoned Burnham boilers altogether, as we operate in their "Boston to Providence" chloride exclusion zone.

Steamhead isn't Steamhead for nothing: "My solution would be a Peerless 63-06. Or, for slightly better efficiency, a Slant/Fin TR-50H with a Carlin power gas burner."

Time to get off the Burnham band wagon. But you also have to tackle your water usage.

Lastly (you can't really blame us) you state: "and piping that multiple experts have told me is fine."

We'd love a photo or two. Just our nature.

jonny88

You said a house correct,with a IN9 why so big?

heatman

Thanks for all the very helpful feedback.

SWEI suggested stainless. Sounds good to me, but I have never seen a stainless residential steam boiler. Do they exist?

KC_Jones says the water loss is too high. I believe that, but how do you go about finding the mysterious leaks? I have never found any evidence of them, nor have two different heating companies that have inspected the system. What good is a 3 gallon per year spec from Burnham if it is not practical to achieve? I also disagree that you "can't design out metal corrosion." Yes you can: de-oxygenating the water, and using way thicker cast iron are two ideas that come to mind immediately for me. Given more time, I'm sure I could come up with others. And if you think these sound too expensive, try the cost of replacing a large steam boiler every 5-10 years. That's pretty expensive too.

In response to BobC, the water is a mix of MWRA and local wells. Chloride is high at 140 ppm. My water use does not include blow down water. My message to Burnham is "140 PPM of chloride. So what. Make it reliable in the face of this since this is a normal municipal water system." If you can't, then tell your customers in advance that the product will only work with some water supplies."

Thanks to Steamhead and RI_Steamworks for their recommendations with respect to boilers. I didn't know that I lived in the "chloride exclusion zone".

Some piping photos are attached:

heatman

In response to jonny88, the boiler is big because it is a big old victorian house (5,000 sq ft) with very little insulation in a cold climate. (Boston)

SWEI

heatman said:

SWEI suggested stainless.

I never actually suggested stainless.

My intent was to point out (in my somewhat roundabout manner) that if 304 SS is rated for 100 PPM then plain cast iron at 100+ PPM doesn't have a chance.

What good is a 3 gallon per year spec from Burnham if it is not practical to achieve?

That number is entirely practical to achieve.

you "can't design out metal corrosion." Yes you can: de-oxygenating the water

You left out both chlorides and sodium. You can forget about "de-chlorinating" which isn't what the name seems to imply. Doing so merely dissociates (hyper)active gaseous Cl2 into two Cl- ions. You need to either remove the offending ions (think RO or ion exchange) or chemically buffer them so they don't attack the ferrous components of your system.

using way thicker cast iron

We did that for decades, and it worked pretty well. It also gave us boilers that weighed roughly twice as much and burned 35% more fuel.

ChrisJ

Just thinking out of the box here but.
How about some water treatment?

Wonder how one of the IN9s would last under the same exact conditions, but with 2 Steamaster tablets in it.

Rhomar also makes a great product.

As had already been said, 2 gallons a week is excessive. Start checking packing nuts, vents and the connection between valves and radiators.

KC_Jones

Have you gone around to every pipe joint with a mirror to find the steam leaks? Steam is invisible you won't "see" the leaks. You must do your due diligence before blaming a manufacturer. Everything you posted tells me your house is destroying the boiler and has been for years. I won't get into the Burnham quality discussion, but I will say in my opinion that system with that amount of make up water would eat probably any boiler on the market.

heatman

Thanks again for the additional feedback. I learned some things here. One is that steam leaks are apparently not typically obvious, and that a system should be using very little make-up water. Having said that, all of my radiator valves and vents have been checked and re-checked, and, in some cases, replaced, to little or no avail. Perhaps some problem ones have been missed. It sounds like a tiny leak can be a big problem. (Refer to my earlier comments about these steam boilers being too fragile.) Imagine that there is a tiny leak in some pipe joint buried in a floor or wall. I don't think I'm going to find that without tearing the house apart. Probably cheaper to buy a new furnace every ten years as much as I hate to say that.

What about systems to pre-treat the boiler feed water? Large commercial boilers use these, but the ones I have seen are not practical for residential applications. If the primary goal is to eliminate contaminants like chloride, I can accomplish that with a tank of distilled water that I fill once a year. De-aerating the water also seems possible with various electric hot water heaters. It would only have to run just prior to a boiler fill operation. Seems crazy, I know, but given the boiler's sensitivity to naturally occurring chemicals (chlorides and oxygen) in my water, and an inability to find the leaks, it would at least be more robust than trying to control my municipal water supply and find leaks that can't be found. Sounds like there is a market for a smaller, residential water pre-treatment device. Anyone know if there is such a device?

SWEI

If you really can't find and fix that leak...
Caleffi is bringing out a small DI system for just this sort of thing. http://www.caleffi.com/usa/en-us/catalogue/hydrofilltm-na570912 is the big one for contractors doing system commissioning.

heatman

In response to KC_Jones question: "Have you gone around to every pipe joint with a mirror to find the steam leaks?" Yes for the joints that are exposed (at radiators, etc.) but most of the joints are elbows and unions inside walls and floors so this is not practical. I could pressure test each leg of the system in an attempt to isolate the problem slightly, but that doesn't help much since there are 15 radiators and 4 legs. Maybe it allows me to rip up only part of the house. And the location of buried piping is not known to me.

My earlier point about this, is that steam systems leak a little, and short of ripping the whole house apart, you aren't going to fix it. There needs to be a better solution that is robust enough to deal with these small leaks. That's why I put it back on the manufacturers. They should not assume ideal conditions with near zero leakage. It's just not achievable except in a brand new installation. How many old steam heated homes have you seen with no leaks? I venture to say it is the exception, not the rule.

Put yourself in my position. I have hired 3 different contractors to address the water leak problem, and they have not been able to. My conclusion is that this is not a viable path to addressing the problem. I have tried it multiple times with no success. On to something that might work, like pre-treating the make-up water. Sounds a lot easier and less expensive than ripping the house up. The manufacturers should have recommended solutions for pre-treatment. With that in place, you would have a robust system that works with leaky systems (the norm for old houses), and corrosive water supplies (the norm in my area). Wouldn't that be better in the end? You install it and it just works. No worries about the water supply. No worries about a valve or vent developing a small leak. I would pay thousands for such a system, since I have paid tens of thousands for replacement boilers.

Wouldn't a water distiller and perhaps pre-heater do the job? Remove all contaminants and most of the oxygen. And it could be low capacity since make-up water requirements are low volume and infrequent. You only run it when needed so electricity usage would be negligible. Just poking around, I can buy things that do that for hundreds of dollars. Add some control electronics for a few bucks and you got yourself a steam boiler life lengthener. Any takers? Maybe it already exists, but I can't find ones that are smaller than a Buick since they are intended for commercial.

ChrisJ

The only steam systems I've seen using a ton of water are broken ones. Mine which is from the mid 1920s uses a gallon per season.

I've found steam leaks tend to leak when the pipe is cold but stop rather quickly as soon as it gets hot. This includes valve stems.


And I'm going to recommend water treatment again as it'll likely solve the problem. Contact Rhomar for recommendations.

http://www.rhomarwater.com/

They have Boiler Pro 903, and they even sell STEAM-PRO which they describe as a premixed ready to use boiler fluid.


Just because running plain water in your boiler rotted it out (which is a bad idea in general in my opinion) doesn't mean a simple quality treatment won't solve the problem.


Fix what leaks you can, and contact Rhomar. There's no need to go to any extremes. The previous boiler in my house rotted out twice in less than 9 years. My current boiler with treatment is 5 years old and like new. In fact, when I drain any water from it, the only rust I find came back from the radiators. The block it self doesn't appear to be rusting at all and if it is, it's incredibly little.

Water treatment is important.

hot_rod

With high TDS andChlorides a demineralized fill water may be a good option. For any new or replaced boiler in those water conditions

But the bigger question as KC presented is where is all that water going?

jumper

Too long ago I sold water solutions. After several years I ran out of customers. Most prospects roll the dice.

gennady

hot rod said:

With high TDS andChlorides a demineralized fill water may be a good option. For any new or replaced boiler in those water conditions

But the bigger question as KC presented is where is all that water going?

leak inside of the boiler above water level?

Fred

gennady said:

hot rod said:

With high TDS andChlorides a demineralized fill water may be a good option. For any new or replaced boiler in those water conditions

But the bigger question as KC presented is where is all that water going?

leak inside of the boiler above water level?

That would be my guess too.

SWEI

Simple enough to check for one of those.

Multiple experts in what?