i have 2 water heater tanks located at the attic. they were installed as parallel or tandem.
my house is 2-storey that was built about 2 years ago.
i have this weird problem this morning because the 2 showers in the 2nd floor dont have hot water.
All other faucets in the 2nd floor and 1st floor have hot water also the shower in the 1st floor has hot water.