Best Coil Heat Exchanger For Hot Tub

Rinnai RU160iN Condensing Tankless Hot Water Heater, 9 GPM, Natural Gas, Indoor Installation

Endless Hot Water: Enjoy unlimited hot water flow throughout the house.
Energy and Space Efficient: Space-saving design conserves energy as it heats only when necessary.
Optimal Water Pressure: Up to 7 GPM hot water flow rate for a powerful, constant stream.
Instant Heating: Equipped with Circ-Logic - Pair with an external pump to reduce wait time for hot water via scheduled or on-demand recirculation.
Guaranteed to Last: 15-, 5-, and 1-year residential for heat exchanger, labor, and parts, respectively. Wifi monitoring..

Endless Hot Water: Enjoy unlimited hot water flow throughout the house.
Energy and Space Efficient: Space-saving design conserves energy as it heats only when necessary.
Optimal Water Pressure: Up to 10 GPM hot water flow rate for a powerful, constant stream.
Instant Heating: Equipped with Circ-Logic - Pair with an external pump to reduce wait time for hot water via scheduled or on-demand recirculation.
Guaranteed to Last: 15-, 5-, and 1-year residential for heat exchanger, labor, and parts, respectively. Wifi monitoring..

Endless Hot Water: Enjoy unlimited hot water flow throughout the house.
Energy and Space Efficient: Space-saving design conserves energy as it heats only when necessary.
Optimal Water Pressure: Up to 7 GPM hot water flow rate for a powerful, constant stream.
Instant Heating: Equipped with Circ-Logic - Pair with an external pump to reduce wait time for hot water via scheduled or on-demand recirculation.
Guaranteed to Last: 15-, 5-, and 1-year residential for heat exchanger, labor, and parts, respectively.

Endless Hot Water: Enjoy unlimited hot water flow throughout the house.
Energy and Space Efficient: Space-saving design conserves energy as it heats only when necessary.
Optimal Water Pressure: High-performance up to 6.5 GPM hot water flow rate for a powerful, constant stream.
Enhanced scale detection lessens possibility of serious, long-term damage to unit.
Guaranteed to Last: 10-, 5-, and 1-year residential factory warranty for heat exchanger, labor, and parts, respectively.

Endless Hot Water: Enjoy unlimited hot water flow throughout the house.
Energy and Space Efficient: Space-saving design conserves energy as it heats only when necessary.
Optimal Water Pressure: Up to 11 GPM hot water flow rate for a powerful, constant stream.
Instant Heating: ThermaCirc360 technology provides faster hot water with a built-in recirculation pump, timer and thermal bypass valve - ideal for homes without a dedicated return line.
Guaranteed to Last: 15-, 5-, and 1-year residential for heat exchanger, labor, and parts, respectively. Wifi monitoring..

Endless hot water, On-demand usage, Compact, Space saving, Energy conservation.
Computerized safety features, No pilot light to have to worry about.
Safety features include freeze, overheat, surge protection, and troubleshooting diagnostic codes.
Satisfies the 2012 SCAQMD Rule 1146.2 for Ultra-Low NOx Emissions.
Primary heat exchanger utilizes commercial-grade copper alloy for 25 times better heat transfer than stainless steel, Integrated controls and power cord as standard features.

Endless Hot Water: Enjoy unlimited hot water flow throughout the house.
Energy and Space Efficient: Space-saving design conserves energy as it heats only when necessary.
Optimal Water Pressure: High-performance 6.5 GPM hot water flow rate for a powerful, constant stream.
Multiple venting options available including PVC/CPVC using the Ubbink Concentric to Twin Pipe adaptor allow for an easy installation.
Guaranteed to Last: 12-, 5-, and 1-year residential factory warranty for heat exchanger, parts, and labor respectively.

Endless Hot Water: Enjoy unlimited hot water flow throughout the house.
Energy and Space Efficient: Space-saving design conserves energy as it heats only when necessary.
Optimal Water Pressure: High-performance 7.5 GPM hot water flow rate for a powerful, constant stream.
Multiple venting options available including PVC/CPVC using the Ubbink Concentric to Twin Pipe adaptor allow for an easy installation.
Guaranteed to Last: 12-, 5-, and 1-year residential factory warranty for heat exchanger, parts, and labor respectively.

Endless Hot Water: Enjoy unlimited hot water flow throughout the house.
Energy and Space Efficient: Space-saving design conserves energy as it heats only when necessary..
Optimal Water Pressure: High-performance up to 5.3 GPM hot water flow rate for a powerful, constant stream.
Enhanced scale detection lessens possibility of serious, long-term damage to unit.
Guaranteed to Last: 10-, 5-, and 1-year residential factory warranty for heat exchanger, labor, and parts, respectively.

Endless Hot Water: Enjoy unlimited hot water flow throughout the house.
Energy and Space Efficient: Space-saving design conserves energy as it heats only when necessary.
Optimal Water Pressure: High-performance 6.5 GPM hot water flow rate for a powerful, constant stream.
Multiple venting options available including PVC/CPVC using the Ubbink Concentric to Twin Pipe adaptor allow for an easy installation.
Guaranteed to Last: 12-, 5-, and 1-year residential factory warranty for heat exchanger, parts, and labor respectively.