Gas (Natural Gas Or Propane)
The most common choice for whole-house use. Highest flow rates, works well for larger households. Needs proper gas supply and dedicated venting.
An authorized Rinnai dealer · Mr. Plumber, Inc. · Since 1958
Everything You Need To Know Before You Go Tankless.
New to tankless water heaters? Start here. We'll explain what they are, what your options look like, why homeowners switch, and how tank and tankless honestly compare, with no jargon and no pressure.
Serving Columbia, Lexington, Irmo, West Columbia and the wider Midlands of South Carolina.
Start Here
What Is A Tankless Water Heater?
A traditional water heater is a big metal tank, usually 40 to 80 gallons, that keeps water hot 24 hours a day so it's ready when you need it. That means it's constantly using energy to reheat water you may not use for hours, and once the tank runs empty during a long shower or back-to-back loads of laundry, you wait 30–60 minutes for it to recover.
A tankless water heater (also called an "on-demand" water heater) skips the tank entirely. When you open a hot tap, cold water flows through the unit and past a powerful heat exchanger that warms it instantly. Close the tap and it shuts off. Because it heats water only as it flows, it can run essentially forever without running out, and it isn't paying to keep a tank hot in between.
Most units are about the size of a small suitcase and mount on a wall in the garage, a closet, or outside. They run on natural gas, propane, or electricity, and a properly sized unit can supply multiple fixtures at once.
Your Options
The Tankless Options We Install
Which one fits depends on your home's fuel, your hot-water demand, and where the unit will live. We'll size it with you.
Electric
Simpler to install where gas isn't available. Great for a single bathroom, an addition, or point-of-use spots far from the main heater. May need an electrical panel upgrade.
Condensing
A high-efficiency gas unit that captures extra heat from its own exhaust, lowering operating cost. Uses PVC venting. Our usual recommendation for a main unit.
Whole-House
One correctly sized unit serving the entire home. The typical setup for a family replacing an aging tank.
Point-of-Use
A small unit dedicated to one far-off fixture such as a workshop sink, a guest bath or a wet bar, so you're not waiting for hot water to travel.
With A Recirculation Pump
Adds near-instant hot water at the tap and reduces water waste. A good add-on for larger homes with long pipe runs.
Why Homeowners Switch
The Benefits Of Going Tankless
Endless Hot Water
Showers, dishwasher, and laundry at the same time without anyone getting a cold surprise.
Lower Energy Bills
No standby loss from keeping a tank hot. Most homes see a meaningful drop in water-heating costs.
Lasts About Twice As Long
Roughly 20 years of service life versus 10–12 for a typical tank, and most parts are replaceable.
Reclaims Your Space
A wall-mounted unit frees up the footprint of a bulky tank in the garage or closet.
No Tank To Leak Or Flood
A failed storage tank can dump 50 gallons onto your floor. There's no tank here to rupture.
Cleaner Hot Water
Water isn't sitting for days in a tank collecting sediment and rust.
An Honest Comparison
Tank Vs. Tankless
Tankless is not automatically right for every home. Here is the real trade-off, side by side.
Storage Tank
40 to 80 gallons, kept hot around the clock
3 pro 5 con
Tankless
Wall mounted, heats only while water is running
5 pro 3 con
-
Con
Limited to the tank. Once it empties you wait 30 to 60 minutes for it to recover.
Hot Water Supply
ProContinuous. It heats as the water flows, so it does not run out.
-
Pro
Lower. A cheaper unit and a simpler installation.
Up-Front Cost
ConHigher. The unit plus any gas, venting or electrical work it needs.
-
Con
Standby loss around the clock just to keep the tank hot.
Energy Use
ProRuns only when water flows, so most homes see the bill drop.
-
Con
About 10 to 12 years.
Lifespan
ProAbout 20 years, and most parts are replaceable.
-
Con
A large tank standing on the floor of a garage or closet.
Footprint
ProA unit about the size of a small suitcase, mounted on the wall.
-
Con
A failed tank can put 40 to 80 gallons on your floor.
Flood Risk
ProThere is no tank sitting there to rupture.
-
Pro
An occasional flush, then replace the whole unit when it fails.
Maintenance
ConAnnual descaling is recommended, especially in hard water.
-
Pro
Fine until the tank runs empty.
Simultaneous Demand
ConHas to be sized correctly, or flow drops when many taps run at once.
The short version. Tankless wins on supply, running cost, lifespan and space. A tank still wins on up-front cost and on being simple to service. Which of those matters more depends on your home, your fuel and how much hot water you use at once, and that is exactly what we work out with you before you spend anything.
Ready To Talk It Through?
Tell us about your home and how you use hot water, and Mr. Plumber, Inc. will recommend the right unit and give you a straight quote, including anything your install needs to meet code.