Finally figured out why we were burning through dishwashers every few years

I went through the same cycle with our KitchenAid a few years back. Our water is even worse, testing at 11 gpg, and I didn't realize how much that mineral buildup was choking the circulation motor. I was convinced the machine was a lemon because the filter would get this weird, waxy grey sludge after just a dozen loads. I actually moved away from pods entirely. Those things are convenient but they dump way too much soap for a standard cycle, and if your water isn't soft, that excess detergent just bonds with the calcium and turns into a cement-like paste. I switched to using standard Cascade powder so I could control the dose. I also started adding a tablespoon of Lemi Shine to the pre-wash cup.

The temperature thing is spot on. I had to dial back our Rheem water heater because the internal sensor on the dishwasher was getting confused by the incoming heat and cutting the cycle short. Since I started running the kitchen faucet until it's hot before starting the load, the spray arms stay clear and I haven't had to poke a toothpick into a nozzle in over eighteen months.

I had a similar issue with my Bosch 800 series, but for me, it wasn't the water heater—it was actually our "pre-rinsing" habit that was killing the machine. We were rinsing everything so clean before loading that the turbidity sensors thougth the load was done after fifteen minutes. beacuse there wasn't enought food debris for the enzymes in the detergent to latch onto, the soap ended up being way too abrasive on the plastic impellers and seals. Instead of switching to liquid, I stuck with the Finish Quantum tabs but started using the built-in water softener compartment. A lot of people don't realize their Bosch has a spot for dishwasher salt in the bottom. Once I filled that up and set the hardness level to H04 to match our local utility report, the scale stopped forming entirely. Now I just scrape the big chunks into the bin and let the machine actually work. It feels wrong to put dirty plates in, but the pump sounds much smoother now that it’s not circulating sand-like mineral grit.

This is so helpful! I’m totally new to owning a place and I’ve been staring at my control panel like it’s a spaceship. I had no idea the water heater setting coud acutally break the seals on a pump, that’s wild! I’m definitely going to check my temp settings tonight before I run another load.

Quick question though, since you guys clearly know your stuff—does anyone here use a tankless water heater? I’ve heard they can sometimes cause more sediment issues in the pipes, and now I’m terrified it’s going to fry my brand new washing machine too!

Spot on about running the faucet first to get that heat up. One thing I've noticed with these Bosch units when the water is that hard is the check valve gets hit the hardest. If you don't have a solid high loop in your drain line, that mineral-heavy backwash just sits against the pump seal all night.

I had to replace my check valve twice before I realized my drain hose had sagged. It's a cheap part, but it stops that scale from settling back into the motor housing and cooking the gaskets while the machine is off.

Since you've got a Bosch, check if yours has the built-in water softener reservoir in the floor of the machine. I realized after two years that I was ignoring that little 'salt' light, and once I actually started using dishwasher salt, the scale issues stopped entirely. It treats the water before it hits the pump, wich saves the seals. Also, instead of the toothpick, I started popping the spray arms off and soaking them in a 50/50 mix of hot water and vinegar or CLR. It dissolves the gunk inside the arm that you can't reach with a pick. Just make sure you rinse them good before they go back in or you'll have a suds explosion.