WH lifetimes

Discussion in 'Water Heater Forum, Tanks' started by Thatguy, Aug 22, 2009.

  1. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    27,230
    Location:
    Cave Creek, Arizona
    heaters

    There is NO general life span for a heater. Gas heaters can last 20 years, but there are also many which are exchanged during their 6 year warrany period. Electric heaters, generally, have a shorter life span, but many also go bad within the normal 6 year warranty. Water softeners usually PROLONG the life of the heater because it creates a more compatible form of deposits in the heater.
  2. Thatguy

    Thatguy Homeowner

    Messages:
    1,459
    Location:
    MD
    I pay 16¢/kwh ($4.69/therm) and $1.10/therm of NG.

    If an elec. WH stays at 90% its whole life, a gas WH that's down to 21% from 60% would consume as much of my money per month as the elec. one.

    Now to find a link that measures or calculates gas WH decrease in efficiency over time.

  3. Of course not, you're an opinionated homeowner that thinks your personal experience is the rule of thumb for many, which leads down to maybe a couple of water heater experiences which I deal with weekly.

    Should I or anyone trust your opinion at this point given your limited point of view on such matters of information trading? I think not.

    I love people who doubt logic, first hand experiences with product knowledge. I'm no different than any other plumber on this site but I have no problem being the most descriptive to the nonsense that was thrown on this thread.

    Am I expected to discount my firsthand experiences of weekly water heater replacements to listen to a couple homeowners speaking from solo experiences, cherishing the fact you have dinosaurs in the basement still producing hot water without a "known" cost to you because you can't gauge against a new one?


    I replace a lot of water heaters around the 5 to 9 year mark quite often. 99% of them were never touched since the day they were installed.


    What does that mean, intelligent homeowners? That means the heater never was drained, never removed of sediment, never had an anode rod replaced inside the water heater when the rod substantially started to lose its ability to protect the steel tank. Do you all comprehend this well known fact about water heaters?

    Secondly, hard water and high water pressure also has deciding factors about these water heaters. That constant flexing of mild steel in water heater tanks allows for the paper thin glass lining to pop off the inside of the tank walls, exposing bare steel to be in direct contact with water. We know where this leads.

    The constant "flexing" of the tank between pressure variations creates microscopic cracks in the steel tank that start an ongoing process of leaks that can close themselves back up, calcify shut. If you could cleanly strip an older water heater apart and see how many other points of failure has before the big one that leaks rears its ugly head, you'd see that the tank's condition was poor before the final leak arrived.

    I've seen burners that were completely covered with carbon buildup, scaling of the flue walls inside the heater or even further up the exhaust system that contributed to the demise of the tank's efficiency.


    People change their tv's almost every 5 years these days

    Their phones

    Their cars


    IF, people could visually and financially see how inefficient a water heater becomes by viewing the condition inside the tank, they'd replace them more often.

    The penny-pinchers would see the issue and instantly understand that there's no way that unit is producing the efficiency as it once had when initially bought.


    Yahoo just posted a link about now they are going after appliances, cash for fridges. I have a 24 year old freezer that still keeps food frozen, but there's no way in hell it is efficient like the day it was installed.

    The gaskets are wore out on the lid, the coils have probably never been cleaned (like the majority) and after that many years, you cannot expect anything of the nature to be cost efficient product.

    It's the attitude of "it still runs it's fine" attitude that creates a glutton of extra expense not visually seen in the electric or gas bill. It's there, but until you know the costs incurred, for many it just simply does not exist.


    I wonder why every water heater I pull out weighs 20 to 70 pounds more than what it weighed when it was first installed.


    Oh I don't know, maybe I'm a plumber and have the back pains and hemmorhoids to prove it?



    Continue with the circling of the wagons, it's not getting anywhere but debunked.

    The majority put-it-in-and-forget-it with water heaters. Job security for me because the homeowner isn't educated enough to understand that the water heater is always the lowest point of the potable water system inside the structure. It's a given that it's going to be the collector of everything brought in from the public or private water supply. Every single water heater made today is a water heater with a boiler drain attached to the sidewall, not the bottom of the tank which indirectly seals the fate of that water heater given the fact that sediment, once entering that unit will never leave it.

    It's a fact that my rhetoric on these subject matters will be used as resource links for understanding plumbing systems and situations across the globe. The information I put out there coincides with manufacture's recommendations and product knowledge reality.
    Last edited: Aug 24, 2009
  4. Thatguy

    Thatguy Homeowner

    Messages:
    1,459
    Location:
    MD
    http://en.wikipedia.org/wiki/Ad_hominem
    :(

    Nobody doubts what you see.

    How we should interpret
    what you see
    so we can use this info
    to our benefit
    is
    what's at issue.

    BTW, if the homeowner knew how inefficient his WH was becoming, would he keep it anyway because he paid for it and it still sort-of works?
    http://en.wikipedia.org/wiki/Sunk_costs
    The same with an old car that gets lousy mileage (a hidden cost) but it still runs and the cost of a new one is considerable and is not a hidden cost.


    The manufacturers usually "have a dog in this fight" so I discount what they say except on issues where they are afraid of lawsuits.

    Getting new TVs, phones & cars when the old ones still substantially work could be considered "vanity purchases" but nobody competes with the neighbors about who has a better, faster, stronger water heater; purchasing one is a necessary evil if you want hot water.
    Last edited: Aug 24, 2009
  5. And that's why I'm here, because I know homeowners benefit from what I type. That's why I try to be as concise, accurate as possible in my statements and analogies of how I represent the plumbing industry in my state and abroad.

    As fast as I can state that I follow mfg's recommendations, I can point out the flaws in such representations just as quickly and if you stick around here long enough, I have a reputation of speaking my mind about which ones make life hell for you and me and which ones are providing a great product and reputation.



    I mentioned to you about my freezer. I'm just like you about not spending money unless it is absolutely necessary. I will not replace it until it quits working or someone tells me of the huge costs involved to fix it. I'm tired of de-icing the damn thing once a year but I've never had much success replacing rubber strips around doors on appliances because the damn things always come off easy, but never go back on easy.


    Now,

    My water heater hasn't been drained since the day it was installed. I'm 54' from it as I type, right now. I even put a damn date on it so I'd remember to drain it once year...but guess what?


    I'm a homeowner, I keep putting it off, It's producing hot water and I keep saying "I'll do it this weekend" and everything else becomes a priority.

    That's about the clearest honesty anyone can give that I'm preaching it but not doing it, and I don't expect the majority of homeowners to drain their water heater.

    It's a 40 minute task, it involves numerous steps and for all my customers and non-customers there's a page that people can print off my website that they can take with them to the front of their water heater or tape it to the tank so they know how to do it.

    It's my give back contribution to society and this wonderful profession of plumbing I've come to love. But one thing I never hold still for is misleading or misinterpreted information about plumbing. I'll stand up in ritual and describe what I see to a tee if what is being told doesn't match reality.

    That's why you have me in discussion in this topic, as it doesn't represent the 100's of water heaters that have been installed by me personally.

    I hope for everyone to have long lasting water heaters but the manufactures don't want that, they build them to break. A favorable situation is a long lasting water heater, meaning "normal" water quality, "normal" water pressure and the owner taking preventative steps, including actual purchase of a well built unit from the get go.

    In the late 80's I replaced a water heater for $200, that was with me supplying a $125 water heater, the parts to switch out and $70 labor. Cheap.

    Every water heater today, especially PowerVent water heaters suck! to replace along with every water heater today has different dimensions from the one coming out.

    Rarely do I ever get a straight changeout, and I'd have a heart attack or erection, possibly both if I ever graced that luxury again given the way these water heaters are built to purposely be different in size all the time.


    A regular gas water heater is $400-$500 these days with FVIR technology that is mandatory by the government. I'll gladly take a water heater that's aging and "spend a little more" each month than follow a ritual of replacing a water heater every 6 years.


    But that doesn't negate/nullify the statements I made about how much efficiency they lose.

    In essence the guy driving a high efficiency car in the driveway getting 48/38 mpg has no clue what sits in his basement that literally zaps electricity and natural gas as it gets progressively older.

    If you remember in high school when they had us do the science experiment with the charcoal briquettes in the fish bowl and those formations were created with chemical interaction...

    that is what it looks like inside a water heater as it ages. Buildup. Insta-hot water dispensers made from Insinkerator? Every one of those I've taken out are solid full of corrosion/buildup from the end product of heating water.

    I think I've stated enough for the masses that my knowledge on this subject matter is pretty evident. It's time for tea and two 3 packs of chocolate zingers. :D



    Dunbar "Livin' for the sugar high" Plumbing
  6. Runs with bison

    Runs with bison Member

    Messages:
    897
    Location:
    Midwest
    My personal experience spans enough geographies and homes that it is unlikely to be mere coincidence. It sure isn't "solo." Plus I've not seen your guideline anywhere else, making it highly suspicious. And you have a serious conflict of interest in recommending such rapid replacement. One wonders if this is really about the homeowner's econ, or about your wallet?

    Should anyone trust an opinionated plumber that can't/won't prove what he says? No! They are a dime a dozen. Ask half a dozen tradesmen a question an you get half a dozen answers...often mutually exclusive. That's precisely why many of us end up doing the work ourselves once we do some research. I've had enough of plumbers that price gouge, don't come prepared, and that I have to scrounge my own tools and parts for because their massive truck/van doesn't seem to carry anything of value to actually complete a job.

    That describes the problem with your response perfectly. You have problems with logic and get all beligerent. As it is my experiences are first hand as well, but you can't explain them.

    The primary nonsense in the thread is coming from you. You've been challenged and refuse to provide any support for your claim.

    The average life I've seen listed for gas water heaters is 11-13 years, based on reality and a wide array of users. Consider now your claim of efficiency falling by half in only 6 years... It doesn't add up.

    My father-in-law's water heater is about 20-30 years old IIRC--I was shocked when I checked its tag. That thing still heats like a champ, didn't have any problems with running out of water. Now tell me about this 6 year theory again? Losing 50% of its efficiency in 6 years...I suppose dropping by half again every 6 years. Gee, if it started at 58% efficiency it should be somewhere between 2 and 7% efficiency by now and the flue would have a constant glow.

    Unlike you I'm handy with numbers and can gauge the cost to me, which is why I'm calling you out on this one. I however doubt you can accurately do the economics of a change out.

    And did you interview the homeowner and look at their bills to record gas use over the life of the tank?

    Did you also go out and identify how many water heaters did not require replacement during that time and get their gas records as well so that you could determine their efficiency decline? Seeing only the ones that are failing gives you a really skewed perspective. Apparently you never considered that.

    Actually, I do. I've done quite a bit of heat exchange equipment design and troubleshooting. I've also solved problems with high pressure boiler chemistry control to prevent tube ruptures.

    I'm well aware of the retrograde solubility of hard water minerals. And have cleaned more water heater tanks than I care to recall.

    Nope, I tend to hang onto things for 10-20 years. My TV is 19 years old. I maintain stuff. It's cheaper than replacing it every 6 years... Plus my TV is much more energy efficient than the new LCD's/plasmas.

    You might have bought into the disposable society mindset, but many of us have not.

    Actually, being a penny-pincher is exactly why I keep track of utility use and find your assertion dubious. I'm accustomed to doing the economic analysis of both my home and process gear.

    It's easy enough to compare things like this with a Kill-a-watt. I did that very thing for a 14 year old fridge that I cleaned up (before and after). It was surprisingly close to the original energy guide after I cleaned the coil thoroughly. Didn't stop me from selling it to buy a bigger, more efficient fridge that I wanted, but I'm not fooling myself about the economics. There are some actual published figures for expected degradation of refrigerator performance, mine was in much better shape than they suggested.

    A 24 year old freezer would have been inefficient from day one compared to current gear or even early/mid 90's. But that's because performance standards have improved. There is some loss of efficiency over time depending on both wear and maintenance. If you haven't measured it, then you don't know.

    It's not there if you can't see it in increasing kwh, ccf, etc. It's pretty easy to isolate the nat. gas usage each year for the water heater. That's what I've done in looking through the past decade of bills.

    Ego has clearly gotten the best of you.

    Your real argument is that folks don't maintain them and therefore they should treat them as disposable so that you can change them every 6 years Hey, I've got a thought...why not suggest that people maintain their gear and save a bundle both on operation and change out? Seems that might be more useful to your global audience. ;)
  7. Wow, I'm sitting here staring at my computer screen watching the glow from your post like I should be impressed.


    Can I have your autograph, the permission to post your writings on my wall?


    I enjoy your "personal experiences" as there's not a name, a company, or a face to back up anything you just said.


    Just someone that didn't like being instructed the facts about products that consistently break down and lose their efficiency as they age.


    Tell me, "Runs with Mike Tyson"

    In your travels in geographies and tell tale histories of homes, water heaters and freezers...

    tell us if you've ever seen a water heater cut open after a few short years of use,

    and are you willing to do this to your water heater when it fails, not "if".

    ???

    Also,

    Tell me great one, when I have to replace a water heater that's 6 years old, why is it very apparent that something evidently didn't hold up to the 20 years you're preaching? Was it built on a monday, friday?


    Let's see your scribed words and comical mathmatical equations you've surmised on your legal sized notebook, and I'll start believing you're just not here for the entertainment and the kind patting of my ego.

    Seems that you feel entwined to discredit what I've made a profession out of, thinking you're geographies trump the resident professional.

    Continue, I have cheese puffs and french onion dip. I'm prepared for this revelation of water heater knowledge unfound that I never knew was placed in my very hands every time I replaced one, installed one, discussed why I was there. :p


    Let us know who you are "runs with bison" as your quite the intimidating scholar you be...:eek:
  8. Runs with bison

    Runs with bison Member

    Messages:
    897
    Location:
    Midwest
    In other words, Dunbar, you've got nothing. You refuse to back your claims with anything concrete and those of us with different experiences should believe reality is only what you say it is in your area.

    I'll do you one better. I'll continue to track this water heater's gas use until it fails (or I replace it) to see if/when it tumbles. So far water heater gas use is down about 33% in the past year (from 18 therms/month to 12), but I've been reducing wall/pipe losses and hot water consumption by various devices/appliances. I'm approaching half of the Energy Guide rating.

    I'm still scratching my head over your electric water heater claim... How again is the electrical efficiency lost? Sure the elements will burn out and quit working, but nearly all of it from beginning to end is going into the tank because it is a resistance heater. The tank can be full of sediment but the heat is still going into the water. The only other place it has to go is surface losses...which are not changing much. Ask an engineer buddy how to draw a box around a system, it's one of the first things you learn.

    Now if one really wanted to prove a point about efficiency losses in the gas fired heater, the solution might be in measuring flue gas temps. If the efficiency falls dramatically that heat has to go somewhere during burner operation. And that somewhere is up the flue in a traditional non-power vented model.

    Efficiency loss is not necessarily the same as poor recovery or lost working volume.

    I'm not "preaching 20 years." Unlike you I don't pretend to know when the water heater walls will begin to leak nor how rapidly efficiency will decline. I'm not trying your "one size fits all" approach.

    If efficiency fell off as rapidly as you believe, energy conservation sites and greenies would be all over it.
  9. Heres a water heater cut open for you

    [​IMG] Most of the lime probably blew out when it exploded but you can still see the scale build up


    give him hell Dunbar...



    [​IMG] here is an electric with the gunk that the bottom
    element was buried in... That is not efficient...

    Honestly, Runs with Bulls,

    they really do lose their efficieny rateings
    over time and really do cost more money the older they get..


    Listen to Dunbar....him very wise.....
    Last edited: Aug 24, 2009
  10. Thatguy

    Thatguy Homeowner

    Messages:
    1,459
    Location:
    MD
    if anybody is still listening

    Replacement time

    Here's a method that works for gas water heaters that become less efficient [very rapidly for the purposes of this example].

    This method can be modified to use on cars, with a resale value, that gradually become less fuel efficient and cost more for repairs each year.

    Cost new for gas water heater = $600

    Cost for fuel, 1st yr., $400
    2nd yr, $600
    3rd yr, $800 (it's already at half of its original efficiency)
    4th yr, $1000

    Figure the cumulative cost for each year:
    1st, $400
    2nd, $400 + $600 = $1000
    3rd, $1800
    4th, $2800

    Add the price when new to the above column
    1st, $1000
    2nd, $1600
    3rd, $2400
    4th, $3400

    Now divide each column entry above by the year number
    1st, $1000
    2nd, $800
    3rd, $800
    4th, $850

    The cost/year drops at first, and then starts rising. In this example you should replace it at about 2.5 years.

    This is best done on a spreadsheet.
  11. Runs with bison

    Runs with bison Member

    Messages:
    897
    Location:
    Midwest
    I went back through the utility records for the only water heater replacement I've ever had (nat. gas). It was in a place I rented for a long time. It wasn't a necessary replacement, the landlord wanted to do it after the plastic drain valve failed. The tank still looked good inside and had little scale or sediment. The existing water heater was at least 8+ years old, don't remember the model. The new one was a Kenmore I believe (Sears install, wasn't my choice.) Gas use in the years before and after were unchanged averaging about 18 ccf/month during the summer. (Same old furnace with pilot the whole time, same showerhead, etc.)

    There seems to be some confusion here about terminology: efficiency is not the same as recovery time or effective capacity. This is especially noticeable in electric water heaters as elements foul and burn out.


  12. First of all,

    I'm not the 5 post wonder you are.


    Secondly, I moderate/admin plumbing forums across the internet, but I just started plumbing last friday. :D



    Second, you don't "grasp" sediment that lines the bottom of a water heater on gas models

    you don't "grasp" electric water heaters that can have sediment issues that reach the lower element which is the worker bee of the tank in producing hot water, that when it is submerged in sediment like the picture above shows...the energy guide is wasted print on the heater.

    Comprende? Si?

    Run with Bison,


    Have you never seen an electric water heater element pulled out of an older, sometimes relatively newer water heater at times when a layer of sediment bakes itself to the element, and you hear what sounds like bacon sizzling when the upper thermostat calls for action and you know your water heater is operating?

    Are we on the same planet or did I make a wrong turn at Mars today. :confused:

    Do you think that efficiency isn't lost when buildup is on the elements OR in the bottom of the tank?

    DO you think Master Plumber Mark shoved oatmeal in that water heater to make up stories?



    Are you serious?

    So, when a tank's capacity is lost due to mineral buildup, and the conversion is.....wait.


    You fill in the blank. You tell me what the conversion is for capacity against ready to use hot water, figure out the # of gallons and then tell me what's the factor used in consideration for doing conversions from gas to electric, electric to gas and what needs to be increased or decreased when doing so.





    Did the picture above your post ever make you think that sediment can bury the bottom element...???

    Never heard of scale/lime buildup on an element?

    You mentioned burn out and quit working...wouldn't that be a dead end statement in reference to knowing that it's going to be instantly replaced to make it operable? Hello?

    "The tank can be full of sediment but the heat is still going into the water" images.jpg


    What happens to thermal transfer/dissipation when someone cooks food and beans burn in the bottom of a pot? It traps it, interrupts the cycle of heat rising to the top like all water heaters are designed to do...

    that's why cold water enters the tank through the dip tube,

    that's why electric water heaters operate by the lower element to heat the incoming cold that rises to the top for the ready to use hot water,


    the top element is only for sustaining ready to use hot water when the heater has been inactive for a period of time.


    The statements you're making are easy to blow holes through with how much you don't know about the operation of a water heater.


    "But my dad works on computers, and he's got tools. We can use his tools and fix things." :D



    If you're going to dance with me, at least dance to the same song with me.

    Now I have a reason to use my camera more effectively so the proof is in the pudding to reference what I already know.


    You're going to get charged for the ear plugs for every water heater I cut open for the visuals so this "unknown" by years of knowledge comes out and people can point and giggle at the empty statements I just filled for you.


    It almost sharpens the pencil for me, it really does when reality and perception get mauled over by someone who can type and argue. I'll be waiting for your response on what you should know in the paragraph above to see if I should stop.

    No, I can't do that, I got pictures coming! Whoops, here's one with a little more of that non-efficiency rust buildup:

    WAH-WAH HEATER.jpg
  13. Runs with bison

    Runs with bison Member

    Messages:
    897
    Location:
    Midwest
    This is why it can be so hard to communicate with techs/tradesmen, they routinely misapply theory while scoffing at edumacated engineers. Let's review how to draw the box:

    Energy efficiency is a measure of how much energy goes into the water versus how much ends up going to the surroundings (flue losses, piping, walls, etc.) If it goes into the sediment (see electric) it is still in the tank with the water. The energy still has to get out either with the water or out through the walls/piping. The effective capacity of the electric heater goes down as the element fouls and if sediment gets high enough to cover it, etc. Efficiency does not. Unless the water in the tank along the walls is much hotter than before, the losses to the environment on electric are going to be essentially unchanged. If you lost X watts out the walls and piping before you will still lose X watts. So for a given amount of hot water usage, your efficiency will be unchanged. Now if you crank up the temp to compensate for lost capacity, you will see greater losses as the delta T to ambient is greater. However, considering that standby losses for electric water heaters are small (90+% energy factor), you won't see much decline in efficiency even then. You are likely to hear complaints about the hot water running out early...been there, done that. Funny thing is, the water heater can work like crap...but still get about the same electrical efficiency per gallon of heated water.

    I've pulled out enough electric elements that I have some feel for the sedimentation/scaling aspect. Never had to replace one of the tanks though...they seemed to live on for the dozen or so years I lived with/serviced them. I've scraped out a lot of that carbonate in the bottom. I do recall the capacity dropping off, which was an indication the "death spiral" had begun and that I would soon be replacing the bottom element.

    The death spiral in a nat. gas heater will be different than an element failure. Sure sediment will reduce capacity and recovery time at some point. An efficiency loss will result and the wall temps will be higher than before. The question is one of degree. Until that burner is having a really hard time heating the water the energy efficiency is not going to change much. Water's ability to transfer heat is a wonderful thing for those of us with heat exchange design experience. Heat transfer coefficients on the liquid side of an exchanger tend to be an order of magnitude above that on the non-condensing gas side--two orders of magnitude when phase change is occurring. This will handle some scaling before efficiency suffers appreciably. When heat transfer does begin to suffer appreciably the tank is likely starting a death spiral. Flue temps will rise (something you can measure) because the burner will be firing hard, but the heat transfer coefficient is plummeting. Wall temps in the flue will shoot up and the exiting gas will be hotter. This will increase corrosion rates on the flue walls/base.

    You can't predict when a wall failure will occur due to corrosion because there are so many types (particularly the exterior wall failure posted earlier--hint: it's not the heat transfer surface, looks like the external weld seam but I could be wrong.) I've seen and troubleshot enough different corrosion/cracking mechanisms in many types of systems and metallurgy (including several grades of titanium, several types of hastelloy, duplex stainless, monel, inconel, brass, copper, aluminum, silver as well as differing grades of stainless and carbon steels), so I know better than to make some sort of bold statement about when something must be replaced without inspecting it.

    Putting a six year life on it wasn't smart to begin with because use will also factor in. If one is firing the thing hard and long, cycling it frequently, and/or running high tems I would expect the sedimentation rate to differ from one being run milder. Then there are other factors such as location (water chemistry), maintenance, and water softeners.
  14. Ahh you're an engineer. Now I know why this thread interested you so much. You know this situation from an entirely different angle than what I represent.


    However, (and I've said this countless times) that I never retract a statement on the internet. I stand by my 6 year statement because soon enough I'm going to get my hands on one with a camera and start disecting these jewels to show the various situations from different areas that water/pressure/mineral content plays havoc on a water heater and its warranty.

    What sucks is I just had a scrap guy take away 9 water heaters I had sitting at the shop. Those would of been a great show and tell as they all came from differing cities, all had a reason why they were replaced, with the common denominator of they all leaked but one. 1 customer took a preventive approach and the sediment buildup was ridiculous.



    In your statement about sediment on a gas water heater, If a thermostat is set to 150 degrees to produce hot water for an aging unit, and the customer is complaining of "running out of hot water" in these conditions...

    Where is the efficiency of that aging water heater, even though it is not leaking.

    Property owners command hot water demand, they almost always don't care about the workings of the situation, they just want hot water like a new tank offers.

    That thinking enters a different form of thinking when the end user considers a tank "lasting" a good deal from a consumer perspective if they feel that the unit is operating at a cost efficiency the same as the day it was installed. That's the point I'm making and replacement, especially with the new energy guide requirements (Higher R Value ratings) on these tank water heaters make the older ones an unwise choice, especially when a 20 year old water heater will have rail thin insulation wrapping the tank. That's a no brainer that the cost to operate that unit, along with what's hidden inside that tank collecting, affecting the operation of that unit.
  15. Runs with bison

    Runs with bison Member

    Messages:
    897
    Location:
    Midwest
    Dunbar,

    Sounds like we are closer to being on the same page now. I don't doubt that you primarily see the units that were/are badly scaled/sedimented and need replacement regardless of age. I expect you to, that's why folks call you. Unfortunately, through no fault of your own this will produce a skewed distribution. How many calls do you get from customers or non-customers who just out of the blue say, "My water heater is running great after X years, just thought you might want to come see it!" I'm betting you don't, just like plant superintendents never called me to show me how beautifully their equipment was running before it started misbehaving. I got called for help when things were in the ditch as did the mechanics, instrument folks, and other support staff. Often it was for processes I had never worked with, and equipment that was new to me. Afterward, if I wanted to find out how things turned out, I usually had to call them (that typically meant it worked.) They would remember to invite me to some BBQ victory celebrations though. On the other hand, if it didn't work they were sure to let me know...

    I also do not doubt that when gas heaters enter that death spiral their efficiency drops. But the death spiral will likely differ from normal aging where the efficiency hit will be modest (like I said, I've so far not been able to measure it from background on water heaters I've used.) Having to crank the thermostat up is a warning to the owner that the heater is having trouble. Leaks of course are the other obvious indication that time is up.

    I am sincere about wondering about flue gas temps (for non-power vented units.) This should probably be measured an inch or so below/inside the heater's exhaust after a minute or so of burner run time so that external draft into the flue at the top of the heater is removed as a variable. This is one of those things that would require a bit of a history to be useful. Could be a wild goose chase. Figuring out a correlation of flue temp with fouling could be quite useful for both energy conservation and equipment changeout. Changing out equipment early wastes money, but changing it out about the time the death spiral starts could save folks a lot of heartache, and money.
  16. death spiral of a water heater

  17. GoldMaple

    GoldMaple DIY Junior Member

    Messages:
    29
    Location:
    Canada
    My 2 cents

    I had to respond to this post. I'm in the middle of researching water heaters because I'm in desperate need of a new one. My water heater still works but I can't imagine how low it's efficency rating is. It's 27 years old... (John Woods) Here's the thing, I'll bet that it's half full of scale. I have a water distiller that I descale 2 times a year and when I do it has a heavy layer of scale in it. After descaling the unit a gallon of water is distilled in less time.

    My water heater has never been cleaned. I don't even know if it's possible and simply draining the tank is most likely next to useless. I base that assumption on the cleaning of my distiller, where the scale is hard packed and stuck to ALL surfaces. Every once in a while a chunk may break off but it's too big to pour out the drain spout. So, it accumulates and I'm able to clean the distiller because it's small and has a lid that opens.

    I'm a typical home owner when it comes to water heaters. For the most part I just ignore it. As a result my water heater probably looks worse than this one inside............

    Attached Files:

  18. Thatguy

    Thatguy Homeowner

    Messages:
    1,459
    Location:
    MD
    If it's gas it has outlived 96% of its peers.
  19. GoldMaple

    GoldMaple DIY Junior Member

    Messages:
    29
    Location:
    Canada
    Yup, it's gas

    Yes, it's a gas heater and I'm now just realizing that it could blow at any moment....... Based on everything I've been reading a Bradford White would be a good replacement so I'm tracking down dealers in my area and will get one installed soon.
  20. ferd

    ferd New Member

    Messages:
    15
    Location:
    Ohio
    Our WH was installed in 1972! Nothing ever comes out when it's drained.
    So I guess we are ahead of the curve. I credit the longevity with it heating at 65k btu's and we have a softener on well water. We never run out of hot water! I think that by heating at this high rate it is not as efficient but it keeps everything dried out. I've been looking for a new one but can't find a fifty gallon with more than 45k btu short of going commercial. When we change it I'll cut it open to see what's inside.

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