Plumbing tips · October 11, 2026
Tank or tankless water heater
When a water heater wears out, the question comes up: put back a tank, or go tankless? Neither one is right for every house. Here is what each one does well and what each one asks of the house.
How a tank works
A tank heater keeps a set amount of water hot all the time, ready to use. It is simple, it is what most houses already have, and swapping one for another of the same kind is usually the most straightforward job. The trade-off is that once the hot water in the tank is used up, you wait for it to heat back up.
How a tankless works
A tankless heater warms the water only as it flows through, so it does not run out the way a tank does and it is not keeping a tank hot all day. It also hangs on a wall and takes up far less room. The trade-off is that it can only heat so much water at once, so it has to be sized for how many showers and taps run at the same time.
What tankless asks of the house
Switching is often more than swapping one unit for another. A gas tankless usually needs a larger gas line and different venting than the old tank used, and an electric one can need a much bigger electrical supply. Those changes are part of the job, and they are worth knowing about before you decide.
Upkeep on either one
A tank collects sediment and does best when it is drained and flushed from time to time. A tankless needs its own periodic flushing, especially with hard water, to keep scale from building up inside it. Neither one is set and forget.
Which one fits
If the house is used to a tank and the tank has done the job, putting back a tank is a sound choice. If you are short on space, run out of hot water often, or are remodeling anyway, tankless is worth a look. A licensed plumber can look at your gas or electric supply, the venting and how your house uses hot water, and tell you what the switch would actually involve.
Questions we get asked
Will a tankless water heater ever run out of hot water?
It does not run out the way a tank does, but it can only heat so much at once. If too many showers and taps run together on a unit that is too small, the water will not stay as hot. Sizing it right is what prevents that.Can I just swap my tank for a tankless in the same spot?
Sometimes, but often the gas line, the venting or the electrical supply has to change too. A plumber can tell you what your house needs before anything is bought.Do both kinds need maintenance?
Yes. A tank should be drained and flushed to clear sediment, and a tankless should be flushed to clear scale, more often where the water is hard.Plumbing questions we answer
Where we go
Parker, Wise and Tarrant County, out of the shop in Springtown. Springtown, Weatherford, Azle, Boyd, Decatur, Newark, Millsap, Fort Worth and the country in between.
Call 817-487-8866