Korean houses are heated by an underfloor heating system. This type of heating system is quite common in Korea and it’s called ondol, 온돌. Let me show you how to use the Korean floor heating and hot water system.

Many visitors make the mistake of turning on the air-conditioner when they arrive at the house to warm up.
But in Korea, generally, an air-conditioner in the apartment is only used for cooling during the summer which means it has no heating function. Therefore, please don’t turn on the air-conditioner in the winter season.

When you stay in a Korean house, you may find a little controller(thermostat) on the wall. By turning it on, you could get hot water or floor heating(or both). The problem is there are dozens of temperature controller manufacturers in Korea, and all controllers are written in Korean. It might be so confusing as foreigners can’t speak or read Korean. I hope this post can help you keep warm during your stay in Korea.

How to Use Korean Floor Heating & Hot Water System

Please, check the name of the manufacturer first and click the proper links below. Even if the controller is not the same as the one in your house, it will work similarly.

Rinnai Boiler (린나이 보일러)

Indoor Thermostat Type 1. RBMC-43

Rinnai floor heating controller RBMC-43
  1. Power(전원): Turn On/Off (Reset)
  2. Display: Temperature
  3. Hot water(온수): Select to provide a large amount of hot water for bath and shower. Temperature: Low(저) Mid(중) High(고)
  4. Heating(난방): Heating temperature wheel. Low(저)/High(고)
  5. Leave Function(외출): To make the heating system to a low temperature.
  6. Heating Off(꺼짐): To turn off the heating (usually in the summer we use this).
  7. Schedule(예약): Schedules the time to start and stop the boiler.
  8. Room temperature-heating(실온) / Floor-heating(온돌): Choose which one you want to set.

Indoor Thermostat Type 2. RBMC-12

Rinnai floor heating controller RBMC-12
  1. Power(전원): Turn On/Off (Reset)
  2. LED Operation Indicator(운전): Turns on while the boiler is operating.
  3. Only Hot water(온수전용): Select to provide hot water only (no floor heating /used usually in the summer).
  4. Hot water & Floor Heating(난방온수): Select to provide both hot water and floor heating (in winter).
  5. Leave Function(외출): To make the heating system to a low temperature.
  6. Heating(난방수온도조절): Floor heating temperature wheel.
  7. Water temperature(온수온도조절): Low(저온) High(고온).

Indoor Thermostat Type 3. RBMC-28

Rinnai Floor Heating Controller RBMC-28
  1. Hot water(온수): Select to provide hot water (in summer and winter).
  2. Water temperature(온수온도): Low – Mid – High
  3. Floor Heating(난방): Floor heating operated (only in winter).
  4. Floor heating temperature(난방온도): Low(저온) High(고온).
  5. LED Operation Indicator(연소): The boiler burner is ON.
  6. Leave Function(외출): To make the heating system to a low temperature.
  7. Schedule(예약): Schedules the time to start and stop the boiler.
Rinnai floor heating controller functions RBMC-28


Kiturami Boiler (귀뚜라미 보일러)

Indoor Thermostat (CTR-5700)

Kiturami Boiler Controller CTR-5700

1. Display: Displays status such as Current Function(현재온도), Target Temperature(희망온도), Scheduled Start/Stop Time(예약), Burning(운전), and Season(계절).
2. Function: Sets Room(실내), Schedule(예약) and Leave function(외출). > To operate floor heating make a status on 실내(Set Room temperature) mode.
3. Bath(목욕): Select to provide a large amount of hot water for bath and shower.
4. Power(전원): Turn On/Off (Reset)
5. LED Operation Indicator: Turns on while the boiler is operating.
6. Up/Down (올림/내림): Increases or decreases the target value of a specific function.
7. Season(계절선택): Sets heating temperature(Spring:봄, Summer:여름, Autumn:가을, Beginning of Winter:초겨울, Winter: 겨울) or schedules start/stop time.
8. Schedule(예약설정): Schedules the time to start and stop boiler.

Indoor Thermostat Type 1. NR-10E

Navien Floor heating system controller NR-10E
  1. Power(전원): Turn On/Off (Reset)
  2. LED Operation Indicator(운전): Turns on while the boiler is operating.
  3. Floor Heating Temperature Wheel(난방조절): Floor heating operated / Low(-) High(+).
  4. Leave Function(외출): Select to make heating system to a low temperature.
  5. Heating Off(꺼짐): Select to turn off the heating (usually we use this in the summer).
  6. Room temperature-heating(실내): Activate room temperature-heating (in winter).
  7. Only Hot water(온수전용): Select to provide hot water only (No floor heating/used in summer).
  8. Floor-heating(온돌): Activate floor-heating (in winter/similar function with 실내).
  9. Schedule(예약): Schedules the time to start and stop boiler.
  10. Water temperature(온수조절): Low(저) Mid(중) High(고).

Indoor Thermostat Type 2. FR-5

Gyeongdong Navien Controller FR-5
  1. Power(전원): Turn On/Off (Reset)
  2. Display: Displays status such as Room-temperature(실내온도), Water Temperature(난방수온도), Burning(운전).
  3. Only Hot water(온수전용): Select to provide hot water only (no floor heating/in summer).
  4. Floor Heating Temperature Wheel(실내조절): From 10 to 40 degrees.
  5. Leave Function(외출): Select to make the heating system to a low temperature.
  6. Water temperature(난방수온도): Summer(여름 ), Spring/Autumn(봄/가을), Winter(겨울).

These control box samples will help you turn on the heated floor and hot water while you are experiencing the freezing cold weather in South Korea. Let us know if you run into any problems. While you are experiencing the different types of heating systems in Korea, also check out “Things to do in Korea in Winter,” to plan out your winter trip. Korea is surrounded by mountains so it’s the perfect place to go ski and snowboard. Here are the Best Ski Resorts in Korea. If you do not have time to go skiing, check out the winter festivals in Korea as well. It is the perfect place to experience the holidays in another country.

Let us know if you have any questions. We are here to help!



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