How It Works
How Tankless Water Heaters Work
Open a hot tap and cold water flows through a heat exchanger, where a gas burner or electric elements heat it on its way past. Close the tap and the unit stops. Hot water is made at the speed of the flow, which is why sizing is measured in gallons per minute rather than gallons stored.
The practical consequences follow from that design. There is no standby loss from a tank kept hot around the clock, and no stored reserve — the unit will run as long as the tap runs, at the flow rate it was sized for, and no faster.
Exceed that rate — too many fixtures at once on an undersized unit — and the water arrives cooler than asked, because the exchanger is splitting its heat across more water than it was built for.
Every part of tankless ownership flows from those facts: sizing is destiny, incoming water temperature matters, and mineral scale on the exchanger is the enemy the maintenance exists to fight.
The exchanger's material is the quiet engineering fact: stainless and copper exchangers tolerate the Point's water differently, and the choice interacts with the descaling rhythm the household will keep. It is a planning-stage detail, raised once and decided on evidence, rather than a surprise discovered at the first service visit.