Which tankless water heater is right for you?

Hydra Smart RTC

A commercial condensing gas tankless water heater manufactured with a high grade stainless steel heat exchanger to provide endless hot water. The unit has a 10 to 1 turndown and is highly efficient, with a .95 Energy Factor, making it Energy Star certified.

Hydra Smart RT

A residential condensing gas tankless water heater manufactured with a high grade stainless steel heat exchanger to last longer and provide endless hot water. This advanced modulating water heater has up to a 0.98 Energy Factor and a 10 to 1 turndown ratio. It is eco-friendly and Energy Star certified.

Hydra Smart Outdoor

Either the Hydra Smart RT or RTC can be converted to an outdoor unit with an enclosure kit part #7850P-107. This part is sold separately.

How Tankless Water Heating Works

Tankless Water Heaters (commonly referred to as on-demand or instantaneous water heaters) provide hot water when needed versus traditional tank type water heaters, which store the hot water. A major benefit to using a tankless water heater is that it doesn’t produce the energy losses associated with tank type water heaters. The result is increased efficiencies and cost savings.

As soon as a hot water tap is turned on, cold water travels through plumbing to reach a Hydra Smart series unit. The Hydra Smart’s gas burner then heats the water on demand. You will no longer need to wait for tank type water heater to fill up with enough hot water. (HTP does recommend reviewing a tankless water heater’s flow rate outputs)

For homes that use 41 gallons or less of hot water daily, demand water heaters can be 24%–34% more energy efficient than conventional storage tank water heaters. They can be 8%–14% more energy efficient for homes that use a lot of hot water -- around 86 gallons per day. You can achieve even greater energy savings of 27%–50% if you install a demand water heater at each hot water outlet. ENERGY STAR® estimates that a typical family can save $100 or more per year with an ENERGY STAR qualified tankless water heater. (Energy.gov)

Tankless water heaters are typically more expensive than a traditional atmospheric tank-type water heater, but tankless water heaters will typically last longer and have lower operating and energy costs, which could offset the higher price point. As an added bonus, all of HTP’s Tankless Water Heaters are ENERGY STAR certified! The tankless water heaters use a secondary heat exchanger to use 9% less energy than a conventional, non-ENERGY STAR certified gas tankless water heater. The secondary heat exchanger extracts more heat from the combustion gas, cooling it to the point where there is condensation – hence these types of heaters are called “gas condensing.” (EnergyStar.gov)

Sizing Your Tankless Water Heater

If you are prefer a tankless water heater, please review the chart below to calculate the gallons per minute (GPM) of hot water that will be needed for each fixture/appliance. Add up the expected combined flow rates at one given time to calculate your household consumption.

Fixture Appliance Typical Flow Rates
Bathroom Faucet 0.5 – 1.5 GPM
Kitchen Faucet 2.0 – 7.0 GPM
Shower 1.5 – 5.0 GPM
Dishwasher 1.0 – 2.5 GPM
Clothes Washer 3.0 – 5.0 GPM

For tankless water heaters, you will also need to determine your home’s required temperature rise. Use the EPA’s map for average groundwater temperature for guidance. You may want to calculate the difference between ground water temperature and your ideal hot water temperature. The standard is 120 degrees F.

EPA Map of Average Groundwater Temperature in the US

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