Tank or tankless water heater: which makes sense for your house?

How each one works

A tank heater keeps 40 or 50 gallons hot all the time. When it is used up, you wait for it to reheat. A tankless heater has no stored water. It fires when a hot faucet opens and heats the water as it passes through, so it does not run out.

What a tank does well

• Lower cost to buy and install
• Usually a same-day swap using the existing gas line and vent
• Simple to service, with inexpensive parts
• Handles several fixtures running at once without trouble

What tankless does well

• Hot water that does not run out
• Takes up far less space, mounted on a wall
• Uses less gas, because it is not keeping a tank hot all day
• Generally lasts longer than a tank when it is maintained

What a tankless install involves

A tankless heater burns much more gas while it is running than a tank does, so many houses need a larger gas line run to it. It also needs its own venting, and often an electrical outlet nearby. On a first-time conversion, that work is a large part of the price. Replacing an existing tankless with a new one is much simpler.

Hard water matters

The water in Cerritos, Norwalk, and the rest of southeast LA County is hard. In a tank, the scale settles on the bottom. In a tankless, it coats the heat exchanger, and the unit needs to be flushed about once a year to keep working properly. A tankless heater that is never flushed will not reach its expected life here.

Which one for you

If you run out of hot water regularly, plan to stay in the house, and the gas line can be upsized, tankless is worth a quote. If you want hot water back today at the lowest cost, a new tank is the answer. Mickey looks at the gas line and venting, quotes both when both fit, and tells you which he would put in his own house.