The Whole Truth About Tankless Water Heaters

Rethinking Tankless: Here’s The Facts

Debunking misconceptions about cost, cold climates, and high-demand performance. Sidney Baysinger, November 4, 2025

Tankless water heaters are gaining popularity in residential and commercial markets, yet myths persist about their cost, effectiveness, and suitability. Often viewed as expensive luxuries or limited to warm climates, modern tankless systems are versatile, handling cold-weather homes and high-demand applications. Outdated info from early models fuels these misconceptions, but advances in technology make them efficient and reliable for most projects, making them a solid contender in commercial applications.

Common Misconceptions

They Can't Keep Up with Demand

A common myth is that tankless heaters fail when multiple showers or appliances are used simultaneously, leading to cold water.

In truth, proper sizing and design address this. Rheem's Sagar Rotithor says, "A properly sized gas tankless water heater can provide continuous hot water... even under varying load conditions." Rinnai's David Federico adds, "When properly sized, tankless units provide continuous hot water for multiple showers, laundry, and dishwashing—all at the same time."

Cascading multi-unit setups handle larger homes, multi dwellings, and even apartments, outperforming traditional tanks in efficiency and reliability, eliminating "running out" of hot water.

They Don't Work in Cold Climates

Many believe tankless systems struggle with cold incoming water, unable to heat it quickly enough.

Modern units manage wide temperature ranges. A.O. Smith's Kyle Jason notes, "Tankless technology has come a long way... ensuring optimal performance in a variety of climates." Features like condensing units with recirculation pumps reduce wait times.

Noritz's Jared Mead explains output depends on the temperature difference: "The larger the difference, the less hot water... at one time." In cold areas, pair units to double capacity. With right-sizing, northern or mountainous regions get reliable hot water without efficiency loss.

They're Too Expensive

Upfront costs deter many, but long-term savings change the equation.

Navien's Chia Lin states, "While initial cost may be higher... long-term savings may be more for a tankless water heater," due to no standby loss and higher efficiency. Rebates, tax credits, and utility programs often offset differences.

Tankless units last 25+ years, whereas tanks last 9-12 years, with proper maintenance. A household spending $600 annually on tank heating could save up to 40% ($240/year) with tankless heating, recouping costs over time. Advanced features like recirculation pumps and precise controls boost savings.

Contractor Clay Saliba emphasizes lifestyle questions for sizing: family size, simultaneous use. "They can last twice as long... the lifestyle upgrade is worth every penny."

Smarter, Smaller, Faster

Invented in 1897 by Edwin Ruud, Instantaneous (tankless) water heaters have evolved from bulky, free-standing units to sleek, wall-mounted, efficient systems.

Noritz's Mead highlights app-based controls: "All you have to do is use the app... no cellular reception needed." Rinnai's Federico praises Smart-Circ for learning patterns and Rinnai Central for scheduling and alerts.

A.O. Smith's Adapt+ series focuses on easy installation with flexible venting, gas lines, and Wi-Fi for remote monitoring, plus recirculation pumps for quick hot water.

These are just some of the innovations that deliver efficiency, reliability, and convenience.

On-Demand and Always Ready

Tankless systems provide hot water precisely when needed, ideal for busy homes with back-to-back demands.

In commercial settings like restaurants or hotels, reliability is crucial. Noritz's Mead notes: If a tank fails, operations halt; tankless multi-units offer redundancy—if one fails, others continue with no hot water loss.

Navien's Lin adds: Cascade systems with sensors prevent downtime, detecting issues and shutting down safely. This ensures a continuous supply, reducing risks in high-stakes environments.

The Truth About Tankless

Tankless isn't universal—low-demand homes or budget-focused users may prefer tanks. But myths on cost, cold performance, and demand are outdated.

Properly sized and installed, they offer an endless supply of hot water, efficiency, longevity, and features like smart controls.

Saliba shares: "Personally, I love mine... we never run out of hot water. The benefits far outweigh the cost."

Understand your needs and consult Tankless Pros AZ for a system that delivers convenience, savings, and peace of mind.

This article was created by Sidney Baysinger, Owner/Operator of Water Heater Pros (Sacramento, CA) and Tankless Pros AZ (Phoenix, AZ). Contact Sid for free advice and helpful hints at sid@tanklessprosaz.com