Review: Rinnai RUC98IN Ultra Series Natural Gas Tankless Water Heater

Some water heaters are cheap and easy to use, but highly inefficient. Others attempt to balance cost and efficiency to give homeowners a good value investment. Then there is the Rinnai RUC98IN Ultra Series Natural Gas Tankless Water Heater and what it can provide. This is one of the water heaters of any type that has a verified maximum energy factor rating of 0.96. It is also an appliance that offers PVC or concentric venting options, which not every tankless water heater is able to provide.

All of this comes with a maximum BTU rating of 199,000 and ultra-low emissions, giving a home the strong support it needs for consistent hot water on-demand.

Features of the Rinnai RUC98IN Tankless Water Heater

• This water heater does weigh 62 pounds, so it will need to have a supportive installation point.
• It offers a hot water temperature range of 98F-140F for residential installations. There is a commercial installation option that can be purchased separately which will boost temperature outputs to 185F.
• It has a ¾-inch water and gas connection, so homes with ½-inch connections will need to make a change.
• The full BTU range is 15,000-199,000 and the electronic ignition meets the emissions standards of both Texas and California.
• The maximum flow rate of this specific model is about 10 GPM.
• It is an indoor-use only tankless water heater, but it can operate off propane in addition to natural gas.
• Residential warranties are up to 12 years on the heat exchanger, 5 years on parts, and there is a 1-year warranty for labor on the unit. Commercial warranties are reduced on the heat exchanger.

What to Expect with the Rinnai RUC98IN Tankless Water Heater

We did notice that there was a small reduction in water pressure compared to tank-based water heaters when using older high-flow faucets and fixtures. Homes that are still using older equipment may wish to upgrade their fixtures at the same time to take full advantage of what this tankless water heater can provide.

Unlike some other makes and models, we found that this specific unit was surprisingly quiet. Even if you are pulling water at its full capacity, you can barely notice this heater is working when you’re in the same room.

It can be a little tricky to get the hot water heater to activate. We found that it is necessary to run a faucet or fixture at full flow for a couple of seconds to get the water heater to trigger on. Once you do that, you can reduce your flow rate and maintain hot water levels.

The one issue we can see coming up with this particular unit is for homes with hard water or heavy scale. The hot water heater can detect when it needs to be flushed. This process requires hooking up a pump to use a vinegar solution of up to 4 gallons per minute for 60 minutes. It isn’t the easy task to complete.

For homes with larger families or high hot water demands, the Rinnai RUC98IN Ultra Series Natural Gas Tankless Water Heater really does get the job done. It earns our recommendation today.

Click here to compare the price on Amazon and get a great deal.