Just moved into a newly built house a few days ago. This morning, we gave up
trying to get hot water into our master bath after 30 minutes of waiting. The
water from the cold tap was pretty much equivalent to the water from the hot -
both cool (We are in FL). We have a tankless water heater (A O Smith 510) and
the tank was purposely placed on the wall right outside the master bath so it
would be close. Turned the water on upstairs, and about 5 minutes later, we
had hot water coming from tap. THen went back to master bath, and there was
hot water within a minute. But then, only an hour later, again tried to get
hot water in MB, and it took 2 minutes for the water to begin to get warm, but
then a blast of cold water came out and 8 minutes later, hot water showed up.
But it didn't last - after about 30 seconds, it was cold again, and stayed
that way for several minutes until it just became lukewarm, but I gave up at
that point and just turned it off. On the other side of the house (maybe 60
ft away), we never got anything more than lukewarm water. On those instances
where we did have hot water, it was really hot. But it never lasted.
Showering was an adventure. There are absolutely no controls on the hot water
heater. It is run by a remote, which we were never given by the builder, so we
can't even attempt to adjust the heater. But I doubt the heater itself is the
problem. Any ideas? THANKS

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