Rinnai Tankless Water quality limits – RU/RUR/CU
Rinnai Tankless Water quality limits - RU/RUR/CU: reference table for the tankless water heater (SENSEI series): a quick-reference table with notes.
Rinnai Tankless Water quality limits - RU/RUR/CU table
| Contaminant | Maximum level |
|---|---|
| Total hardness | Up to 200 mg/L |
| Aluminum | Up to 0.2 mg/L |
| Chlorides | Up to 250 mg/L |
| Copper | Up to 1.0 mg/L |
| Dissolved carbon dioxide (CO2) | Up to 15.0 mg/L |
| Iron | Up to 0.3 mg/L |
| Manganese | Up to 0.05 mg/L |
| pH | 6.5 to 8.5 |
| TDS (total dissolved solids) | Up to 500 mg/L |
| Zinc | Up to 5 mg/L |
How to use the Rinnai Tankless Water quality limits - RU/RUR/CU table
Find your exact model in the first column and read across the row. Values in the Rinnai Tankless Water quality limits - RU/RUR/CU table are a summary for quick reference; the rating plate on the unit and the manufacturer's manual for your model always decide. If your model is not listed, or a value looks different from what you see on the unit, check the manual before changing anything.
Notes
- Damage from water beyond these levels is not covered by warranty.
- Hard water needs treatment and more frequent flushing; the Service Soon (SS) reminder can be enabled.
Applies to: RU199i/e, RU180i/e, RU160i/e, RU130i/e, RUR199i/e, RUR160i/e, CU199i/e, CU160i/e (REU-N / REU-NP condensing)
Rinnai models this applies to
CU160eCU160iCU199eCU199iRU130eRU130iRU160eRU160iRU180eRU180iRU199eRU199iRUR160eRUR160iRUR199eRUR199i
Rinnai Tankless Water Heater error codes →
Source: Rinnai Tankless Water Heater (Residential) Installation and Operation Manual (100000467) Table 5 p.19; Rinnai Tankless Water Heater (With Pump) Installation and Operation Manual (100000508) Table 5 p.19; Rinnai Tankless Water Heater (Commercial) Installation and Operation Manual (100000504) Table 5 p.19. Written in our own words as a summary; always check the original manual.
General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.