All of these sort of things are just based on hours used. It's like looking at your hot water heater warranty and replacing it when it's over (I live an an area where the PPM of the water is rather high and hot water heater warranties are basically calibrated for water like mine, so we do have to replace them on warranty expiration, most places you at least get a few years or double)

> It's like looking at your hot water heater warranty and replacing it when it's over

Why would anyone do that? Seems like a waste of a hot water heater that probably has a lot of life left.

People that do this probably throw out food the moment it hits the best before date too.

Changing a hot water prematurely is probable less expensive than having one blow the bottom out and flood whatever area it is in. I don't have a basement, so my central unit and water heater share a utility closet in the hallway sharing a wall with a bedroom. It's a pretty bad design flaw, as during the summer of 110°+ temps, it is unnecessarily heating the house. IR temp shows that shared wall from the bedroom side over 90° radiating into that bedroom. </rant>

That's not so much a design failure of the house, as it is a heater that is not sufficiently insulated.

Maybe, but it's a rental, so only some much to be done about that. So much was defined by me as buying a $30 roll of insulating whatever it is that then got stapled to the interior wall of the closet. Took the thermal temp down 15° on the bedroom side of the wall.

also they make hybrid water heaters that will cool whatever space they are in while they heat the water using a heat pump on top

The whole device is a product and experience. He disabled the razor saying he couldn't use his razor blade. You're supposed touse it until it goes to zero and replace as instructed.

If you want a speaker you don't buy Sonos and say I turned off the drm, firmware and added a headphone jack.

If you want filtered air for cheap you buy a box fan with HEPA.

>but there's a perverse incentive here for the warning to undershoot the actual useful life of the filter

Hypothetically, yes, there's a perverse incentive, but is that what is actually happening?

A clogged filter can stress the fan motor which can A) increase power consumption and B)reduce overall product life.

It's not unlikely. A while ago I had to deal with a laser printer that automatically reported the end of the drum's life after 15000 pages or so, even if there were no signs of stripes on the printed pages. The solution was to stick a 220 ohm resistor on the electric contacts between the drum and the rest of the printer. The printer would sense the resistor (which is present on genuine new drums too) as a signal to reset the page counter. Once the resistor gives a puff of smoke it can be removed, and the old drum can be used until its true end of life.

What does it take to burn a resistor? It sounds terrible to me. Guess it was hot all the time?

Depends on the wattage/power rating of the resistor

It was a through-hole 1/4W resistor. It burnt in about 5 seconds as far as I remember.

And it is for the consumer to decide which path to take. Not the product itself.

Until the consumer complains that the air purifier isn't doing its job and thrashes the company online, and changes for a model from a competitors.

Most consumers aren't really capable of this type of nuance.

This sounds like a completely made up problem, I don’t think this ever happens.

A clogged filter is obviously full of dust and grime, anyone who can use a vacuum cleaner can understand that

> A clogged filter can stress the fan motor which can A) increase power consumption and B)reduce overall product life.

you got it completely backwards, unless you have a very fancy and expensive ECM motor.

Increasing resistance decreases power draw, as the fan needs to do less work. You can test this by hooking up a vaccum cleaner to a killawatt and blocking the intake.

There may be concerns about cooling the motor, but it really doesn't take that much air movement to dissipate heat.