Yet another Bosch dishwasher question

For those of you with recent model Bosch dishwashers, have you noticed if the initial rinse (like the first 15 minutes or so of a 2 hr 15 min cycle) is with hot water or just lukewarm?

The reason I ask is that I just opened up my dishwasher during the initial rinse to put a couple of extra things in, and was surprised to discover that the water inside was not hot. Seemed weird. Opened it up about 5+ minutes later, though, and it was substantially warmer.

I find that it’s helpful to run the hot water in the sink next to the machine. I don’t know about your home / pipes, but it usually takes mine about 30 seconds - a minute to actually start producing fully hot temperature hot water. And it’s my belief that the Bosch heats the hot water that’s already coming through the pipes up a few more degrees, so if you want it to be max heat right at the start, you kind of need to prime the pump.

Or that could just be superstitious, energy wasting nonsense. It has become part of my dish washing routine. Try it out!

I had a repairman advise us to run the kitchen sink hot water prior to running the dishwasher as well.

My Whirlpool does this as well. When I noticed it, it had more than enough time to heat up, so I just figured it’s supposed to work like that. It does get much hotter later in the cycle.

Ditto. I’m guessing the reason is that your in-home water heating whether it be tank or tankless is better at heating the water than the unit inside the dishwasher.

[ HOT WATER SOURCE ] -----------------------------------> [ MACHINE ]
                                           ^^^^^ this part holds cold water that needs to go

my shower takes 1 minute to warm up despite an instantaneous water heater. i figured out it’s because the pipe in between holds a lot of water. if the shower is 1.5 gpm, and the pipe in between holds about that much water it means I gotta flush it for a minute.

my solution was to switch it to the bottom tub part so it dumps all the water out in 20 secs or so

I’m pretty sure my Bosch dishwasher is only hooked up to the “hot” water line, so if the water isn’t hot right away that’s either the (no longer hot) water in the line between the dishwasher and hot water heater getting flushed or it’s the hot water heater taking a minute or two to kick in and heat the water. I suspect this may also explain the “run the hot water in the sink first” wisdom, since that would flush the no longer hot water from the pipes and prime the water heater.

Modern homes in California if they are over a certain size are required by law to have a hot water recirculator, whether on demand or constant. Constant means it’s always on and always looping hot water throughout the house. This is a great way to develop pinhole leaks in copper pipes and waste energy.

We have an on demand system, which means instead of running the water in the shower until it gets hot we hit a button (or ask Alexa as I engineered a smart home integration), wait a few minutes, and then we get hot water in two seconds instead of wasting a minute’s worth of water.

oh wow that is fascinating. I have only ever seen them in hotels.

My setup is backwards. The hot water heater is in the garage, so it takes forever for the water to heat up. But it heats up faster when the dishwasher is on. Maybe the water pump in the washer pulls water faster?

Thanks for all the replies. I do generally (maybe not this time) make a point of running the kitchen sink hot water long enough for it to get hot, and luckily my sink is almost directly above the hot water heater in the basement so it doesn’t take long.

Anyway, the dishes came out fine.

As far as avoiding water waste, upstairs where the shower is I have a 5 gallon bucket to collect the water till it comes out hot, then use it to flush the toilet or whatever (especially when it needs cleaning). Doesn’t everyone do that?