HVACopediaRinnai · Tankless water heater
Mute Controller key beeps on/off
What the display is showing
Switches the beep that sounds when controller keys are pressed. Alerts and confirmation beeps for other functions are not part of this.
Applies to: Rinnai SENSEI, SENSEI RX/CX and KCM tankless with a controller
What to do
- Press and hold Up and Down together until a beep is heard (about 3 seconds on SENSEI and RX/CX, about 5 seconds on the KCM MC-601-US), then release.
- Repeat the same press to turn the beeps back on.
Settings for these units
RSC supply connection sizes · SENSEI
| Connection | Size |
|---|---|
| Gas | 3/4 in. NPT |
| Cold inlet | 3/4 in. NPT |
| Hot outlet | 3/4 in. NPT |
| Condensate drain | 1/2 in. NPT |
| Pressure relief valve | M33 thread |
The PRV and its adapter come in the box; PRV must be rated 150 psi and at least the heater Btu/h.
Condensate drain line must stay at least 1/2 in. over its whole length.
RSC water quality limits · SENSEI
| 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 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 | Up to 500 mg/L |
| Zinc | Up to 5 mg/L |
Damage from water above these limits is not covered by warranty.
Hard water should be treated; use the Service Soon (SS) reminder (parameter 03) for flushing intervals.
- RSC clearances to combustibles · SENSEI
- RSC temperature settings available · SENSEI
- RX supply connection sizes · SENSEI RX/CX
- RX water quality limits · SENSEI RX/CX
- RX water treatment and flushing by hardness · SENSEI RX/CX
- RX clearances to combustibles · SENSEI RX/CX
Models that show this code
30 models in SENSEI RX/CX, SENSEI, KCM (RUCS/RUS)
Other codes on the same units
- LOC Controller locked (KCM)
- LPG Initial setting: propane (LPG)
- Lock key Controller locked (key symbol)
- Maint monitor KCM maintenance monitor (flow and outlet temperature)
- ON Hot water running (controller installed)
- Out Initial setting: outdoor installation
- Parameter mode Parameter settings menu
- Parameter settings Parameter (installer settings) mode
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Source: Rinnai N-Series Residential (100000467) / with Pump (100000508) / Commercial (100000504) / RSC SENSEI (100000773) Installation and Operation Manuals, 5.3.1 p.68; Rinnai KCM Series Manual (U328-0700X04), p.55. Summarized in our own words; check the original manual for your model.
For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.