50gal Power Vent turns on at the slightest use of water????

I just installed a Kenmore 153.332050 (50 gallon Natgas power vent) water heater in my basement.

After a couple of weeks of use, I have incrementally lowered the temperature setting all the way down to its lowest point.. After that, it goes into vacation mode.. We still have plenty of hot water.

My question has to do with the frequency that it turns on. If you wash your hands and use a small bit of warm water, the heater turns on. WHAT?? So even if I pull just a couple of quarts of hot water out of it its going to turn itself on to reheat? Is that normal?

Seems to me that the thermostat has a very tight hysteresis (dead-band).

In my old place, I had a normally vented 40 gallon unit and it wouldn't turn on until you used a significant amount of water..

That can lead to something called temperature stacking. Frequent small uses may cause the water to layer in thermal gradients resulting in the risk of scalding. Turning down the temp to combat it can result in the water not being hot enough when there is no water drawn for some time. The better option is to add a tempering valve that blends in some cold water as needed.

So you're saying the tank is stratifying? All the hot water is headed to the top while the controller reads the cooler water towards the bottom?

I have the controller set at 120 but the water is coming out at 135. I used to have our other heater set at 115 and we had plenty of water..