Rinnai tankless water heaters have become popular in recent years due to their efficiency and convenience. However, like any piece of technology, it is essential to ensure that they are configured correctly to work correctly. One of the critical things to set up on a Rinnai tankless water heater is the dip switch settings. In this article, we will discuss the functions of the dip switches, how to set them correctly.

Main Dip Switch Settings

The main dip switch settings for a Rinnai tankless water heater have different functions, such as controlling the gas type, gas pressure, power failure, and factory reset.

  1. The first switch determines the type of gas used, either natural gas (set to “N”) or propane (set to “P”).
  2. The second switch sets the gas pressure for the specific type of gas used.
  3. The third switch manages the water heater’s operation during a power outage, allowing the unit to continue operating on battery power when set to “ON,” or shutting off when set to “OFF.”
  4. The fourth switch resets the water heater to its factory settings when set to “ON” and then “OFF.”

Note: The dip switch settings may vary by Rinnai tankless water heater model, and consulting the owner’s manual is the best way to ensure proper dip switch configuration.

The default settings for the dip switches on almost all Rinnai Tankless Water Heaters Are:

Switch 1: N or P (depending on the gas type)
Switch 2: Appropriate setting for gas pressure
Switch 3: OFF
Switch 4: OFF

It is important to carefully follow the instructions in the owner’s manual when changing the dip switch settings. Incorrect changes may damage the water heater or cause it to operate improperly. Especially if you change the gas switches to the wrong type of fuel.

Additional Dip Switch Settings

Adjustment for High Altitude Installations

To adjust the SW1 DIP switch on your water heater, locate the tan switches and refer to the table below to set switches 2 and 3 based on your altitude. The default setting for the appliance is for altitudes of 0-2000 ft (0-610 m), with switches No. 2 and No. 3 in the OFF position. If you need to change the DIP switch setting, you don’t need to adjust the gas pressure setting for high altitude.

No. 2
No. 3
0-2000 ft (0-610 m)OFFOFF
2001-5200 ft (610-1585 m)OFFON
5201-7700 ft (1585-2347 m)ONOFF
7701-10200 ft (2347-3109 m)ONON

Changing Temperature For Rinnai Tankless Water Heater

By default, your temperature range is limited to 120F+/-, but some users prefer to increase it to 140F. However, there are two different methods depending on the model you own.

If you have a temperature controller:

  • Move the white SW2 dip switches to the right ON position to extend your Rinnai’s temperature range beyond the default.

If you don’t have a temperature controller:

  • Move the tan SW1 Switch #5 to the right ON position to allow the temperature to reach 140F.

Note: I’ve come across information from unofficial sources suggesting that on certain older models, dip switch #6 also controls the temperature. Exercise caution and consult your official owner’s manual for your specific model.

Adjusting Dip Switch #1 For Vent Length

  • Determine the number of 90° elbows in your vent.
  • Use the table below for maximum vent length.
  • Based on the vent length, adjust switch No. 1 (SW1) as follows:
Number of
90° Elbows
Maximum vent length
041 ft (12.5 m) #1
135 ft (10.7 m) #2
229 ft (8.8 m) #3
323 ft (7.0 m) #4
417 ft (5.2 m) #4
511 ft (3.4 m) #4
65 ft (1.5 m) #4

Refer to the number after # on the table above and use the list below for correct Dip Switch Setting.

  1. If the length is greater than 21 ft (6.4 m) then move switch No. 1 (SW1) to OFF.
  2. If the length is greater than 15 ft (4.6 m) then move switch No. 1 (SW1) to OFF.
  3. If the length is greater than 9 ft (2.7 m) then move switch No. 1 (SW1) to OFF.
  4. Move switch No. 1 (SW1) to OFF.

Rinnai tankless water heaters are a great investment for homeowners looking to save energy and enjoy an uninterrupted supply of hot water. However, to ensure that the unit functions correctly, it is essential to pay attention to the dip switch settings. The dip switches control crucial functions such as gas type, gas pressure, power failure, and factory reset. By following the instructions in the owner’s manual and being careful when changing the dip switch settings, you can ensure that your Rinnai tankless water heater runs smoothly and provides you with hot water whenever you need it.

Error Codes That Can Be Caused By Incorrect Dip Switch Settings

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