Hello, I had a relative install a Takaji Jr. in my apartment. It's a small apt., and space was the main consideration for installing a tankless water heater. It's been running great for about 4 years, but now I'm getting hot water that only lasts a few seconds in the shower. Sometimes it doesn't give hot water at all. I've got to turn the hot water shower spigot on and off several times before the hot water is finally consistent. Needless to say this is a pain. Water pressure in the apartment appears okay. As does the hot water for the washer/dryer. I don't have a dishwasher or sink running when I'm trying to get hot water running. My wife thinks that if the washer's running (even if it's just doing a cold-water cycle) that this makes the problem worse. But it's not exclusively the problem (if it is, in fact, a problem at all), because the problem is still present even when no other water source is going. I've also noticed that the water heater is "on" (making that blowing sound) even when the water in the shower isn't coming out hot, when it should. Anyone ever have a problem like this? Or any ideas? Thanks, Thomas.