Rinnai RUC98iN Ultra Series Natural Gas 9.8GPM Tankless Water Heater | Review

This 80 pounds tankless water heater manufactured by Rinnai became available in the market on October 9, 2014 and operates on natural gas. It has a MC-91-2US digital Controller that makes it more efficient than other Rinnai tankless models.

It is designed for indoor use. With its flow rate of 9.8 gallons per minute, this unit is able to provide endless supply of hot water for residential and commercial application.

Rinnai RUC98iN is simply a masterpiece. It has all the trappings of Rinnai tankless heater units and much more. It is energy saving, space saving and has environmental benefits as well.

Features of Rinnai RUC98iN Concentric /Twin pipe tankless heater

High flow rate

Rinnai has a higher flow rate, as it is a whole house tankless water heater. Its 199,000 max BTU and ability to produce 9.8 gallons per minutes means it can comfortably serve several outlets at once. This makes it ideal for commercial application and homeowners with large families.

Concentric/Twin pipe PVC Venting

This is absent in most tankless water heaters. This unit comes with far more venting options, which makes its assembling very easy. You can install the unit yourself as long as you call a certified plumber to inspect your installation. This is acceptable by Rinnai.

The feature also means you get a unit with two venting options. There is no need for an adaptor as it gives you two times the venting options on every installation.

Ultra low Nox emission

Due to its advanced venting system, Rinnai RUC98in is almost soundless. Unlike the older models that constitute noise in the house, you can mount this model in your laundry room or bathroom and will not even know its on except for the red showing on the light indicator.

Energy saving

The unit is energy saving and has an energy factor of 0.98. The mere fact that it uses natural gas is a huge plus for the product. At the beginning there is the tendency it will consume a lot of gas but this gradually reduces with time. Furthermore, gas powered heaters have a higher heating capacity than electric powered heaters; hence cost of running the unit is drastically reduced.

Highly Durable

For residential applications, a 12 years warranty for the heat exchanger, 5 years for the parts, 1-5 years on labor ensures it last for a long time.

For commercial application, its heat exchanger has a warranty for 5 years, 5 years for the parts and 1-2 years warranty on labor.

Bulb Voltage

It has a bulb voltage of 120 volts.


Just as with all Rinnai water heater the product is sensitive and need careful handling.

Its high price tag puts out of the reach of many who might like to have one although it is an awesome unit.

Another thing is that you need to have a certified Rinnai repair personnel to do repair work if it breaks downs but then you are assured of quality.


Review summary     

Rinnai is known for innovative and technological advanced in tankless water heaters, RUC98iN tankless water heater is another example of its high technology. The model has more positive customer ratings than negative. It will certainly give value for the money and recommended for users in need of a solid tankless water heater with 9.8 GPM indoor installations.

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