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mackey
Premium Member
join:2007-08-20

1 recommendation

mackey to Hall

Premium Member

to Hall

Re: Replace TP valve or water heater?

said by Hall:

said by jjoshua:

Yes. HWH tanks are engineered to last the life of the warranty. Anything longer is borrowed time.

I call bullsh*t on that. No one can design (predict) how long components can last accurately enough to do that. If they did design this way, plenty of water heaters will fail before the warranty is up and by plenty, I mean "too many" as far as the manufacturer is concerned. By the same token, many will last longer as well, but companies won't consider that a wash. Every one that fails under warranty is one too many.

Actually, in this day and age material science can tell you exactly how long it is likely to last. No matter how well they build it, there will always be defective units or units that fail earlier then expected. This is built into the cost of the product. When they engineer something to last just the length of the warranty they know a few will probably fail sooner; if the cost of replacing those units is less then how much they save by using thinner/cheaper materials then they have no problem with doing that.

/M

garys_2k
Premium Member
join:2004-05-07
Farmington, MI

garys_2k

Premium Member

True enough, warranty length is a matter of statistics. In this case the manufacturers no doubt look at the type of water it's likely to be exposed to (market-wide distribution of hardness, pH) and go for a 95-99% survival rate for the warranty period. If you have water that's less abusive (higher pH, less damaging minerals) it will last longer.

Part of the equation with water heaters is how much anode rod they supply -- they know that more anode material will make the tank last longer, but adding more than needed to survive the warranty is a waste of money. So, if you're good about keeping up with the anode changes you can definitely beat the system (at least for corrosion, but that's the major failure mode).

I think that the consumer's sweet spot is to not pay for a "premium" heater and be diligent about maintaining it -- regular flushes out the drain and refreshing the anode (or using an active anode). Doing those two things can make even a cheapie tank WAY outlive its warranty, no question. It's just that few people do those things.

StillLearn
Premium Member
join:2002-03-21
Streamwood, IL

1 edit

StillLearn to mackey

Premium Member

to mackey
I agree that the OP should replace the water heater. This is a comment on the other discussions. The life of a tank can be affected by various things:
The water as it enters the house -- acid, base, minerals, and more
Whether there is a water softener
The anode rod material and whether it is replaced (maybe with a powered anode).
The tank construction.
Whether a glass lining got cracked.

I suspect the temperature of the water and the usage might even play a part. If you want to increase the life of your tank, consider replacing the anode. You may need an impact wrench and a big socket. Use teflon tape when you put the new anode in. You do not need to tighten the new anode nearly as much as the old one was tightened.
James_C
join:2007-08-03
Florence, KY

1 recommendation

James_C to mackey

Member

to mackey
Actually no, even in this day and age there are far too many variables to even begin to estimate lifespan more than make a best guess about it or go by historical data on prior designs. Surely you can think of a few variables. Most water heaters last closer to 2x their warranty length than 1x.

They do not engineer them to only last the life of the warranty, except to factor in worst case usage/stress which we should assume isn't the situation unless told otherwise.

They also factor in their company reputation because the people dealing with replacements know a crap unit when they see it.
Shady Bimmer
Premium Member
join:2001-12-03

Shady Bimmer

Premium Member

said by James_C:

They do not engineer them to only last the life of the warranty, except to factor in worst case usage/stress which we should assume isn't the situation unless told otherwise

Actually this is exactly what is done and it is not a simple calculation.

Usage patterns are charted, and a cost analysis is done to determine the appropriate percentage of failures that is acceptable based on unit cost. The target profit margin determines the loss percentage (for failures covered by warranty).

From that the unit is engineered such that the minimum number of units that exceed the warranty lifetime, by percentage, is met.

Warranties are not designed for zero claims, and product lifetimes are not engineered for 100% clearance of the warranty. Everything is a complicated numbers game based on statistics.

Yes, water heaters, like many other products, are engineered based on the warranty. Life beyond the warranty is expected but is gravy for the consumer.
James_C
join:2007-08-03
Florence, KY

James_C

Member

I'm sure you've read that somewhere because in some cases it is true, but in many cases it most definitely is not true. Most products outlast the warranty by quite a margin. It's not "gravy" at all to expect the average product to last multiple times the warranty period. It's not only about replacement cost for the manufacturer, it's also about product reliability as that affects customer perception of brand.

What examples would you like because almost everything I own has this situation? Literally, 90% or more of the products around me have far outlasted the warranty. The other 10% are simply too new for me to make a guess, or I'm too lazy to look up the warranty period. TV, computer components, furniture, vacuum cleaner, water heater, furnace, dish washer, fridge, etc, etc... I'm not going to list everything I own.

While what you wrote seems to make sense on the surface, there's a staggering amount of evidence to the contrary.
Shady Bimmer
Premium Member
join:2001-12-03

Shady Bimmer

Premium Member

said by James_C:

What examples would you like because almost everything I own has this situation? Literally, 90% or more of the products around me have far outlasted the warranty.

There is a big difference between what you, as a consumer, experience and what the manufacturer produces. I already acknowledged that a product may last longer than its warranty.

Do you really think that all production samples have exactly the same lifecycle? Just because your experiences show that products last longer than their warranty does not in any means indicate that manufacturers engineer their products to last that long.

As I already noted it is based on statistics and profit. Some percentage will fail earlier and some will fail later. Products today are generally manufactured such that a company has enough product to last beyond its warranty to generate a profit. This means that some percentage will fail earlier and some will fail later.

I'm not sure of your point, being one sample among millions, that based on your singular experience how a manufacturer could not possibly engineer products that last only as long as their warranty. This is in fact standard practice and there will (as already noted) be some percentage that does fail within warranty and there will be some percentage that does not fail until much longer beyond that.

What other evidence do you have to the contrary? My statements are based on real-world knowledge from real world interactions and discussions.
Shady Bimmer

Shady Bimmer to James_C

Premium Member

to James_C
said by James_C:

While what you wrote seems to make sense on the surface, there's a staggering amount of evidence to the contrary.

Could you provide such evidence? If there is truly a "staggering amount" you should be able to provide this easily.

At one time manufacturers did have the notion that quality products that lasted would in fact have higher sales. Thanks to competition from foreign entities that had different insight this turned out to be be false.

Across most product manufacturing products are engineered to last only long enough such that the producer is able to make a profit while still honoring their warranty. Granted this would be a small percentage of claims during that time, it still does not negate the fact that it is standard practice to engineer products such that a minimum percentage lasts at least as long as their warranty.

I will request again - please provide your claimed evidence that this is not the case. From working with manufacturers in many industries I already know this to be true. While most may find products last longer than the warranty this in no way indicates that a company engineers products to specifically last that long. It only means those samples are part of the statistical distribution on the profit side of the line. Expecting a larger percentage of samples to last longer than the warranty is not unusual and is part of the profit margin determined by the manufacturer.

This is not black and white. Some product will fail before the warranty and some will fail later. The percentage of product on either side is what is the determination for engineering such that enough fails later in order for the manufacturer to still maintain a profit.
James_C
join:2007-08-03
Florence, KY

James_C

Member

Absolutely, shall we start in your home or mine? Whichever, one of us will have to drag out receipts, compare warranties, and note that practically everything both of us own has far exceeded the warranty period.

This is the case in everyone's home.

Sorry but you are simply wrong. You're taking an overly simplistic idea that all a manufacturer would consider is replacement cost when this could only be true in a closed market where there is no competition.

A manufacturer first has to make the sale, either making good money because of their reputation, or setting for far less because everyone considers the product junk.

You can't know something is true when it is only a "at least better than" philosophy about product lifespan. The "at least better than" (warranty) philosophy in no way limits upper lifespan nor determines average lifespan.

Let's get back to the central issue which is, is it really gravy if something lasts longer than the warranty? To most consumers the answer is cearly "No", they'll be quite upset and buy a different brand next time if a product were to fail right at the end of the warranty period. Manufacturers know this is the majority customer expectation and they DO engineer products to last longer than the warranty period.

Products that fail prematurely (even at end of warranty period) tend to come from extreme environments, misuse, or defect... not the typical, targeted application. Again, this is proven by the vast majority of property we all own, and how ironic that we're discussing this in a topic about an 18 year old water heater.

AVD
Respice, Adspice, Prospice
Premium Member
join:2003-02-06
Onion, NJ

AVD to James_C

Premium Member

to James_C
said by James_C:

I'm sure you've read that somewhere because in some cases it is true, but in many cases it most definitely is not true.

what century do you live in? We are living in the era of planned obsolescence and the walmartization of America.
Shady Bimmer
Premium Member
join:2001-12-03

1 recommendation

Shady Bimmer to James_C

Premium Member

to James_C
said by James_C:

Sorry but you are simply wrong. You're taking an overly simplistic idea that all a manufacturer would consider is replacement cost when this could only be true in a closed market where there is no competition.

A manufacturer first has to make the sale, either making good money because of their reputation, or setting for far less because everyone considers the product junk.

I would echo AVD See Profile's question about what century you live in. Price (not value) is the primary factor in most purchases today. If quality was a primary factor for most purchases products manufactured in foreign countries using inferior parts and inferior labor would not have such high sales in the US. For items such as water heaters, for instance, if two choices have the same warranty length but one is 20% less expensive than the other, which do you think will have more sales?

I am certainly not taking a simplistic view, and in an earlier reply I even explicitly stated it is not a simple calculation.

This discussion has gotten far off topic from the OP question so lets get back on track.

The short answer is that 18 years is a good lifetime for a water heater. If an inexpensive repair or part replacement may be made that would be an option but for something this age spending a large amount of time or large amount of money on a repair likely is not worth it.
James_C
join:2007-08-03
Florence, KY

James_C

Member

The thing is, they can only work within what their parts suppliers allow.

Suppose a switch on product X is rated to last for 1,000,000 cycles but it would typically encounter only 2,000. They can't just decide "we'll buy a 2,000 switch to save money", because such switch doesn't exist.

They could say "we'll go with a lower gauge of steel", but you can't get fractional gauges at good price, the optimal thickness to a penny pincher is probably somewhere between two standard gauges.

Same with a glass lining thickness, wire quality, and any other parameter. They can't just decide to spend less to try to aim for a warranty period, only to not spend more than necessary to meet that period.

Again, the proof is everywhere around you. The theory that this is what they do, must then be tested to be proven true. No matter how much they claim that in an ideal world this is the goal, in the real world it doesn't work out that way.

If two choices have the same warranty length but one is 20% less expensive, it's time to look at the reasons why the other is less expensive. Many people do not make the warranty the primary purchase criterion.

If your claim is that an elaborate calculation lets someone sleep better at night thinking they spent the least amount possible, good for them to sleep better at night but this in no way bears on a consumer's expectation that a product shouldn't last longer than the warranty. Again, this is proven to be the existing factual state of things by the actual products' lifespans.