Navien Tankless Water Heater: Force minimum or maximum firing (special operations)
Force minimum or maximum firing (special operations) on a Navien tankless water heater: Special operations hold the burner at a fixed firing rate for combustion checks.
Applies to: Navien NPE-A2 (built-in recirculation) and NPE-S2 condensing tankless water heaters: NPE-150S2, NPE-180A2/S2, NPE-210A2/S2, NPE-240A2/S2
How to fix force minimum or maximum firing (special operations): step by step
- Hold Menu and Back together for 3 seconds and choose 4. Special Operations.
- Pick 1st MIN, 1st MAX, 2nd MIN or 2nd MAX.
- Choose 1. Normal to return to normal operation.
If the unit shows an error code, look it up: Navien Tankless Water Heater codes
Models
NPE-150S2NPE-180A2NPE-180S2NPE-210A2NPE-210S2NPE-240A2NPE-240S2
Source: Navien NPE-A2/S2 Installation Manual, 7.4.2 p.95-96; 7.5 p.98-99, p.105-107. 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.