Turn it on
- 1Press 전원. The screen lights up.
Navien NR-40S in English
A modern flat Navien controller with a black screen and six touch-style buttons: 난방 cycles room / floor / timer, and + / − set the numbers.
What does each button do?
- 1Every __ hours · ○ 시간마다sigan madaIn timer mode: hours between heating runs (3 here).
- 2Timer on · 예약yeyakShows that timer mode is active.
- 3Run __ minutes · ○○ 분 가동bun gadongIn timer mode: minutes of heating each time (30 here).
- 4Heating mode · 난방 (실내/온돌/예약)nanbang (silnae/ondol/yeyak)Press about 1 s, repeatedly, to step 실내 → 온돌 → 예약. Also cancels Away.
- 5Up · +peulleoseuRaises the blinking value.
- 6Hot water · 온수onsuPress, then + / − for 30–60°C. Hold about 2 s for quick hot water (10 min).
- 7Away / hot water only · 외출·온수전용oechul · onsu jeonyongStops heating; hot water and frost protection keep working. Press 난방 to return.
- 8Down · −maineoseuLowers the blinking value.
- 9Power · 전원jeonwonOn / off. Off stops heating and hot water.
What setting should I use?
실내 at 21–23°C, hot water 45°C. For a mostly empty room in cold weather: 예약 every 3 h, 30 min.
How do I…?
Heat the room to a set temperature
- 1Press 난방 (about 1 s) until 실내 shows.
- 2Press + / − to reach 22. It saves by itself.
Use floor (ondol) mode
- 1Press 난방 (about 1 s) until 온돌 shows.
- 2Press + / − to about 55 (range 40–83°C).
Leave for a few days
- 1Press 외출·온수전용. 외출 appears.
- 2To come back, press 난방. The previous heating returns.
Run on a timer
- 1Press 난방 (about 1 s) until 예약 shows with '00 시간마다 00 분 가동'.
- 2While the hours blink, press + / − to set every how many hours (1–24).
- 3Press 난방.
- 4While the minutes blink, press + / − for run time (10–50, in 10-min steps), then press 난방 to finish. Photo 67 shows every 3 h, run 30 min.
Hot water only (summer)
- 1Press 외출·온수전용. On this model, hot-water-only and Away are the same mode.
- 2To heat again, press 난방.
Change the hot-water temperature
- 1Press 온수. The hot-water target blinks.
- 2Press + / − to 45. It saves by itself.
Turn it off
- 1Press 전원.
- 2In winter use 외출·온수전용 instead, so the pipes stay protected.
What do the words on the screen mean?
| 실내 / 온돌 / 예약 | Room / Floor / Timer | Active heating mode. |
|---|---|---|
| 희망온도 | Target temperature | The temperature you set. |
| ○○ 시간마다 ○○ 분 가동 | Every __ h, run __ min | Timer: e.g. '3 시간마다 30 분 가동' = every 3 hours, heat for 30 minutes. |
| 운전 | Running | The boiler is heating now. |
| 외출 | Away | Heating off; hot water and frost protection only. |
| 돼지저금통 | Piggy-bank icon | Gas-saving indicator. Nothing to do. |
| 온수 아이콘 깜박임 | Blinking hot-water icon | Quick hot water is on (ends after 10 min). |
What trips people up on this model?
- To leave Away, press 난방, not 외출 again.
- In timer mode, 난방 also moves you from hours to minutes and confirms. Pressing it too many times can change mode, so check the screen.
- To stop heating without 외출, set the target below the current room temperature.
It shows an error. Now what?
Note any code on the screen and call 1588-1144.
Service line (Korean): 1588-1144
