Most people believe that if something costs more, it has to be better quality. In the case of generic drugs, this is not true, says Gary Buehler, Director of FDA's Office of Generic Drugs. The standards for quality are the same for brand name and generic products..uch of FDA's review of generic drugs and brand name drugs is the same, Buehler explains (See Same FDA Requirements for Brand-Name and Generic Drugs below).
Then evaluate tank water heaters on the same gph basis to determine how many gallons of storage are needed to meet this demand. While tankless water heaters do not run out of hot water, if not sized correctly, the flow rate of that water can be adversely impacted.
And with 50 feet of pipe, it can take a long time for hot water to reach the tap; while waiting all the water goes down the drain. How long you have to wait for hot water depends on three factors: the distance from the water heater, the diameter of the piping, and the flow rate. The effect of distance is pretty obvious: the further hot water has to flow, the longer it will take to get there.