Common Myths About Tankless Water Heater Technology Debunked

Oct 26, 2022 | by Tim Greer |

Rinnai America Corp. Water Heater Tankless Water Heater

Tankless water heaters have grown in favor over the past few decades, but with increasing popularity comes common misconceptions that surround tankless technology. This not only can impact a customer’s decision but also a plumber’s recommendation.

Here I’ll debunk a few common myths that come up during the purchase process.

Myth #1: Tankless doesn’t work with cold inlet temperatures.

One of the biggest myths when it comes to tankless water heaters is that they don’t work with cold inlet temperatures. As an example, Canada sells over 100,000 tankless water heaters per year, handling cold groundwater easily. Most tankless models are designed to heat water as low as 40 degrees F or as high as 120 degrees F. Sometimes this can go even higher. Many of these models can still provide 5 gpm or more at these colder temperatures. That equates to three showers delivering unlimited hot water simultaneously.

Myth #2: Tankless water heaters are expensive to purchase and install.

Due to the increase in material, shipping, and manufacturing costs for larger appliances, such as tank water heaters, the cost of non-condensing tankless units has become comparable to or even less than a traditional tank, especially when factoring in additional local energy rebates.

For condensing tankless units, venting was another large expense both from a material and labor standpoint, ranging in cost from $200 to as much as $1,000. The high cost was due to some tankless units being only compatible with 3- or 4-inch PVC in comparison to the much more cost-effective 2-inch PVC. Over the past five years, the cost of venting a tankless unit has decreased significantly (now vent systems can potentially be less than $100). Plumbers who have been trained in installing tankless technology often can install tankless water heaters in the same amount of time it takes to install a standard tank, reducing installation costs further.

Myth #3: Tankless water heaters are slow to respond quickly to high demand.

Waiting for hot water can be frustrating and often customers mention they are concerned with the increased wait time of the hot water coming out of the faucet. That’s why they don’t want a tankless water heater. The speed of hot water reaching the customer's faucet is determined by the linear pipe distance and diameter between the water heater and the fixture. With a built-in circulation pump that recirculates according to your customer’s schedule, tankless water heaters can provide hot water at the tap when (or before) it’s needed, leaving customers satisfied.

Myth #4: Tankless means upgrading your gas line.

In many scenarios, your customers won’t need to upgrade their gas supply line when choosing to go tankless. Advancements in technology have allowed installers of tankless water heaters to forgo upsizing the gas supply in some situations, eliminating the need for gas line modification. For example, Rinnai’s Sensei Model incorporates a zero-governor gas valve, switching venturi, and turbofan. All of these work together to pull in the right mixture of gas and air to produce energy-efficient combustion. This allows the tankless water heater to self-compensate for any fluctuations in gas or air supply, creating a more forgiving tankless water heater that works despite the marginal supply of gas pressure.

After learning several common myths and truths behind tankless water heater technology, you can help ease any worries your customers might have when it comes to making a purchase decision.

Learn more at www.rinnai.us/tanklesstruths.