Home Improvement → Re: Replace TP valve or water heater?

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.

I would echo AVD '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.

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.