11 Rinnai V75in Tankless Water Heater Review of 2026 For Simultaneous Showers

1

Rinnai RUCS65IN Tankless Hot Water Heater, Natural Gas

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  9.3
• Brand
  Rinnai

Key specs2

Hot water flow rate

Up to 6.5 GPM (5 appliances)

Venting flexibility

Supports concentric venting or twin-pipe PVC and CPVC runs when installed with the Ubbink adaptor.

Pros & cons42

Pros

• Delivers up to 6.5 GPM to run up to 5 household appliances simultaneously
• Accepts flexible PVC and CPVC venting via the Ubbink Concentric to Twin Pipe adaptor
• Includes 12-year heat exchanger, 5-year parts, and 1-year labor residential warranty coverage
• Compact 22 by 14.5 by 35 inch cabinet mounts on the wall to save floor space

Cons

• Lower 6.5 GPM capacity than 7.5 GPM models during high peak demands
• Requires purchasing a separate venting adaptor to use standard twin-pipe PVC lines

2

Rinnai RWM200 WiFi Control Module for Tankless Water Heater, Black,

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  8.3
• Brand
  Rinnai

Key specs2

Wireless range

Up to 300 feet from heater

Mobile app features

• Remote water temperature adjustments
• Real-time energy usage tracking
• System alert notifications and schedule setting

Pros & cons32

Pros

• Enables remote temperature control and operational monitoring via the Control-R mobile app
• Simple two-wire interface supports placement up to 300 feet away from the water heater
• Tracks energy usage patterns and pushes system maintenance alerts straight to your phone

Cons

• Functions only as an accessory and does not heat water on its own
• Requires compatibility with specifically equipped Rinnai models and active home Wi-Fi

3

Rinnai RE180iN Non-Condensing Natural Gas Tankless Water Heater, Up to

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  8.5
• Brand
  Rinnai

Key specs3

Heating capacity

180,000 BTU / up to 8.5 GPM

Warranty protection

15-year heat exchanger / 5-year parts

Maintenance diagnostics

The integrated LED screen provides direct error codes and service reminders to simplify troubleshooting.

Pros & cons42

Pros

• Delivers up to 180,000 BTU and a maximum flow rate of 8.5 GPM for multi-bath homes
• Integrated LED display provides direct error codes and preventive service reminders
• Long 15-year heat exchanger warranty exceeds older standard residential coverage terms
• Compact suitcase profile measures 10.77 by 14.05 by 27.28 inches and weighs 54 pounds

Cons

• Wi-Fi connectivity requires buying the separate Control-R module
• Non-condensing design requires verifying proper indoor metal venting requirements

4

Rinnai RUS75eP Tankless Hot Water Heater, Propane

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  7.2
• Brand
  Rinnai

Key specs2

Fuel type and location

Liquid Propane / Outdoor installation

Fixture capacity

Up to 7.5 GPM (6 appliances)

Pros & cons42

Pros

• Provides up to 7.5 GPM flow rate to handle up to 6 appliances at the same time
• Dedicated outdoor propane configuration eliminates indoor exhaust venting runs
• Supports PVC and CPVC venting options using the Ubbink Concentric to Twin Pipe adaptor
• Backed by a 12-year heat exchanger, 5-year parts, and 1-year labor residential warranty

Cons

• Designed strictly for liquid propane fuel rather than indoor natural gas lines
• Outdoor-only installation leaves unit exposed to freezing winter outdoor conditions

5

Rinnai V53DeN Natural Gas Tankless Water Heater - 5.3 GPM,

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  8.5
• Brand
  Rinnai

Key specs2

Hot water flow rate

Up to 5.3 GPM (4 appliances)

Installation location

Outdoor wall-mounted (Natural Gas)

Pros & cons42

Pros

• Outdoor installation layout eliminates indoor vent ducting through walls or ceilings
• Delivers up to 5.3 GPM to support up to 4 appliances in smaller households
• Lightweight 33-pound build simplifies outdoor exterior wall mounting
• Includes 10-year factory warranty protection on the heat exchanger

Cons

• Max 5.3 GPM flow rate struggles to support concurrent multi-shower usage in cold climates
• Outdoor natural gas configuration is not suitable for sheltered indoor utility rooms

6

NEW Rinnai RX130iN Condensing Smart Sense Natural Gas or Propane

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  8.1
• Brand
  Rinnai

Key specs3

Energy efficiency factor

0.97 UEF condensing rating

Fuel compatibility

Smart Sense gas control automatically adjusts between natural gas and propane connections without manual conversion kits.

Descaling maintenance

Equipped with a Quick Flush feature that speeds up routine lime and mineral flush procedures.

Pros & cons42

Pros

• Versa Vent system enables either indoor or outdoor installation on one chassis
• Smart Sense gas control operates on either natural gas or propane supplies
• High-efficiency condensing operation delivers a 0.97 UEF rating
• Integrated Quick Flush feature simplifies routine mineral descaling flushes

Cons

• Requires buying an optional RX-OVC vent cap separately if mounted outdoors
• Flow capacity tops out at 7.1 GPM, which is lower than larger 9 GPM units

7

Rinnai RUCS75iN Tankless Hot Water Heater, 7.5 GPM, Natural Gas,

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  8.0
• Brand
  Rinnai

Key specs3

Fixture capacity

Up to 7.5 GPM (6 appliances)

Venting flexibility

Allows concentric or PVC/CPVC twin pipe indoor venting through the Ubbink adapter.

Indoor gas requirements

Engineered as an indoor natural gas heater requiring dedicated exhaust routing and professional technician setup.

Pros & cons42

Pros

• Delivers 7.5 GPM to feed up to 6 simultaneous appliances without temperature drops
• Supports PVC or CPVC pipe setups using the Ubbink Concentric to Twin Pipe adaptor
• Residential factory warranty protects heat exchanger for 12 years and parts for 5 years
• Direct natural gas indoor replacement for standard 7.5 GPM residential heaters

Cons

• Weighs 63 pounds, requiring sturdy wall framing and bracket support
• Requires professional technician installation to validate safety and warranty coverage

8

H98-510-S tankless Water Heater Filter Kit for Rinnai tankless Water

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  7.8
• Brand
  VYH

Key specs2

Included components

• 2 tankless water heater inlet screen assemblies
• 1 filter removal tool

Replacement interval

Every 2 to 3 months

Pros & cons32

Pros

• Includes 2 replacement inlet screen assemblies and an installation removal tool
• Helps protect water heater circuits and internal plumbing from dirt and sediment
• Designed for a quick 5-minute filter swap every 2 to 3 months

Cons

• Only fits Rinnai water heater water inlets that match the 0.94 by 1.8 by 0.78 inch screen
• Component kit only, offering no heating capability by itself

9

NEW Rinnai RX160iN Condensing Smart Sense Natural Gas or Propane

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  7.5
• Brand
  Rinnai

Key specs3

Energy efficiency factor

0.97 UEF condensing rating

Heating capacity

160,000 BTU / up to 9 GPM

Descaling maintenance

The built-in Quick Flush port simplifies annual descaling flushes to keep heat transfer surfaces clean.

Pros & cons42

Pros

• Generates up to 9 GPM and 160,000 BTU to supply up to 6 fixtures simultaneously
• Dual-fuel Smart Sense system works with either propane or natural gas
• Ultra-high 0.97 UEF condensing rating minimizes energy waste
• Built-in Quick Flush mechanism makes system descaling fast and straightforward

Cons

• Outdoor installation requires purchasing the separate RX-OVC vent cap
• Control-R Wi-Fi module is not included and must be purchased separately

10

Rinnai RE199iN Non-Condensing Natural Gas Tankless Water Heater, Up to

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  7.3
• Brand
  Rinnai

Key specs2

Maximum flow output

Up to 9.8 GPM (199,000 BTU)

Warranty protection

15-year heat exchanger / 5-year parts

Pros & cons42

Pros

• Pours up to 9.8 GPM and 199,000 BTU for large homes with concurrent high-flow showers
• LED diagnostic display provides immediate status codes and scheduled service reminders
• Features an industry-leading 15-year heat exchanger and 5-year parts warranty
• Compact non-condensing chassis weighs 52.1 pounds for manageable wall placement

Cons

• Requires substantial gas supply capacity to support the high 199,000 BTU burner demand
• Built-in recirculation is not included and requires stepping up to the REP199iN model

11

H98-510-S tankless Water Heater Filter for Rinnai tankless Water Heater

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  7.2
• Brand
  VYH

Key specs2

Screen dimensions

0.94 in x 1.8 in x 0.78 in

Replacement interval

Every 2 to 3 months

Pros & cons32

Pros

• Provides two replacement inlet filter screens measuring 0.94 by 1.8 by 0.78 inches
• Prevents sediment intrusion into the heat exchanger to maintain water heater efficiency
• Enables routine filter maintenance in under 5 minutes every 2 to 3 months

Cons

• Does not include a dedicated filter removal tool in the package
• Requires verifying exact water heater circuit inlet compatibility before purchasing

Last update on 2026-10-10 / Affiliate links / Images, Product Titles, and Product Highlights from Amazon Product Advertising API

Can a 7.5 GPM indoor natural gas tankless water heater run simultaneous showers?

Yes, a 7.5 GPM natural gas indoor unit can supply concurrent household demands, though total delivered volume depends on your incoming water temperature. Units delivering up to 9.8 GPM with a 199,000 BTU burner provide higher capacity to support multiple fixtures at once, while 7.5 GPM handles standard family routines. If a remote bathroom experiences flow delays during heavy morning demand, adding one of our instant hot water heater options at the sink helps protect shower pressure without overloading the central line.

What venting configurations do indoor Rinnai tankless water heaters require?

Venting requirements depend on the specific heater design, with manufacturers offering multiple venting options on select units and Versa Vent systems on condensing models. Indoor models require dedicated exhaust routing through an outside wall or roof, so you must verify termination clearances before planning your layout. Physical cabinet sizes also differ between models: non-condensing versions measure 10.77 by 14.05 by 27.28 inches, while other indoor models measure 22 by 14.5 by 35 inches. Check the installation manual for your specific model to verify exact vent material compatibility and clearance spacing.

What gas line supply size does an indoor tankless water heater need?

Gas supply line sizing depends on the unit's total BTU rating and the run length from your gas meter. Indoor natural gas models range from 130,000 BTU and 180,000 BTU up to 199,000 BTU. A gas line that is too small can cause burner errors or lukewarm water when other gas appliances run at the same time. Confirm your pipe diameter, incoming gas pressure, and meter capacity with a licensed technician before installation to ensure the unit receives sufficient fuel.

How often should you service or replace the water heater inlet filter?

Replace or clean the tankless water heater inlet screen assembly roughly every 2 to 3 months for optimum dirt-holding capacity. Replacement packages like the H98-510-S filter kit provide two screen assemblies along with a dedicated filter removal tool for quick removal. Keeping this screen free of scale and sediment ensures water enters the heat exchanger without restricted flow or unexpected pressure drops at your faucets.

Can you adjust Rinnai tankless water heater settings from a smartphone?

Yes, remote adjustment is supported on equipped units by installing an accessory such as the RWM200 WiFi control module. This device uses a simple two-wire interface to establish a connection with your local Wi-Fi network. Once linked, the smartphone app lets you monitor heater status and adjust target water temperatures without walking down to the mechanical room.

How does incoming winter water temperature impact tankless flow rates?

Cold incoming groundwater forces the heater to consume more energy to reach your set temperature, which reduces the delivered gallons per minute. A unit rated for up to 7.5 GPM or 8.5 GPM in mild climates will yield lower flow during cold winter months because the burner must bridge a steeper temperature gap. Check your regional winter groundwater temperatures against the heater's BTU rating so you can verify that simultaneous fixtures will still receive full hot water flow on freezing days.