Correct and that would lead one to think that it would last longer. The problem is that it doesn't work that way. When I tear down a heater to find why they have failed, most of the time it is bacause the contacts are bad. Either the current welds themn together and they are full on or they arcing causes the contacts to stop making contact and they won't heat. The reason the contacts go bad is due to their tiny size and the number of times they open and close. Looking at a heater, you find there is usually a bi-metal spring with the contacts all inside a glass or metal tube. When the air in the tube get cool, the bimetal bends and closes the contacts. This turns the heat on and the air in the tube gets hot until the bimetal bends the other way. The large heat coil makes this cycle much more frequent than a smaller heat coil. The heater rarely fails due to the coil going bad but due to the contacts which control the heat coil. Bigger coil, more cycles, and quicker failure. If the water temperature were being sensed rather than the air, the bigger coil would be fine. That can't be done with a cheap heater as the contacts and bimetal would have to be in the water mixing water and electricity.exasperatus2002 said:generally the bigger heater will have to run less to maintain the set temp then the smaller unit would.