CON4 · Sauna Controller · Dry / Steam · 3-9KW · 220V · In stock
What Is the CON4 Sauna Oven Controller?
The CON4 sauna oven controller is a digital control unit that manages the heating elements, temperature regulation, and timing functions of a residential or light-commercial sauna room. Rated for 3-9 kilowatts at 220V single-phase, it switches the high-current heating elements (sauna stones/rocks heater) via internal relays or external contactors, reads a temperature sensor placed inside the sauna room, and maintains the user-set temperature by cycling the heater on and off. The CON4 supports both dry sauna mode and steam (wet) sauna mode, where water is ladled onto heated stones to produce bursts of steam, though the controller itself does not generate steam — it simply manages the heater temperature accordingly.
In short: The wall-mounted digital brain of a sauna room — you set the temperature and timer on its display, and it switches the 220V heating elements to heat the sauna rocks to the right temperature, with safety features like overheat protection and timed auto-shutoff.
What You Need to Know About Sauna Controller Installation
1. Power Rating Must Match Your Heater
The controller is rated for 3KW to 9KW heaters. If your sauna heater draws more than 9KW (which would be unusual for residential 220V single-phase), this controller cannot handle the load — the internal relays or the terminal block will overheat and fail. If your heater is below 3KW, the controller may still work, but the temperature regulation may be coarser because the minimum on-time is designed for a larger heater. Check the rating plate on your sauna heater for its wattage before ordering. The power wiring from the controller to the heater must be sized for the full heater current (9KW at 220V = approximately 41 amps — use 6mm2 or 10 AWG minimum copper wire).
2. Temperature Sensor Type and Placement
The CON4 controller uses a remote temperature sensor (typically an NTC thermistor or PT100 RTD) that must be installed inside the sauna room at the correct height — usually about 15-20 cm below the ceiling and away from the direct heat path of the heater. If the sensor is placed too close to the heater, it reads artificially high and the controller never reaches the target room temperature. If placed near the door or ventilation inlet, it reads artificially low and the room overheats. The sensor cable should be routed away from the heater power wiring to avoid electrical interference coupling into the temperature signal.
3. Dry Mode vs. Steam Mode: How the Controller Handles Both
In dry sauna mode, the controller maintains the set temperature (typically 70-90 degrees C) by cycling the heater on and off. In steam mode, the user manually pours water onto the hot stones — the sudden evaporation creates a burst of steam that briefly raises humidity and perceived heat. The controller does not inject water or generate steam on its own. Some CON4 models include a humidity sensor or a dedicated steam generator relay output; verify which features your specific model has. A steam generator (a separate appliance that boils water and pipes steam into the room) requires different control logic than a standard sauna heater controller.
Key Specifications
| Model |
CON4 Sauna Controller |
| Power Rating |
3-9 KW / 220V AC, single-phase |
| Modes |
Dry sauna / Steam sauna |
| Control Type |
Digital electronic thermostat with timer |
| Sensor |
External temperature probe (verify type: NTC/PT100) |
| Condition |
New |
Frequently Asked Questions
Can I replace my old mechanical thermostat with this digital controller?
Yes, provided the heater wattage is within the 3-9KW range and the voltage is 220V single-phase. The main considerations for retrofit: (1) the temperature sensor type must match the controller input — if your old system used a different sensor, you may need to install the sensor that comes with this controller; (2) the controller's physical cutout dimensions must fit your existing wall box or panel; (3) the wiring from the controller to the heater elements runs at full heater current — ensure the existing wiring is in good condition and adequately sized. Always install a dedicated circuit breaker and residual current device (RCD/GFCI) per local electrical code for sauna installations.
What safety features does this controller include?
Typical CON4 controllers include: overheat protection (shuts off the heater if the sensor reads above a safety threshold, typically around 110-120 degrees C), a timer function with automatic shut-off after a set duration (preventing the sauna from running indefinitely if someone forgets to turn it off), and a door-sensor interlock input on some models. Verify which features your specific CON4 variant supports. Additionally, sauna electrical codes in most regions require an independent overheat cutout (a separate thermal fuse mounted on the heater itself) that operates independently of the controller — this is a heater-level safety device, not part of the controller.
The display lights up but the heater does not get hot — what should I check first?
Check in this order: (1) Verify the set temperature is higher than the current room temperature — the controller will not energize the heater if the room is already at or above the setpoint. (2) Check the timer — many controllers require the timer to be set (not at zero) before the heater output activates. (3) Measure voltage at the heater output terminals on the controller when the display indicates heating mode — if no voltage, the controller's internal relay may be faulty. (4) If voltage is present at the controller output but the heater is cold, measure resistance across the heater element terminals (with power off) — an open circuit indicates a burned-out element. (5) Check the external overheat cutout/thermal fuse on the heater body — if it has tripped, press the reset button.
Does this controller work with a steam generator, or only a traditional sauna heater?
The CON4 is primarily designed for traditional sauna heaters (the type with stones/rocks). A dedicated steam generator is a different appliance with different control requirements — it needs water level sensing, a water fill valve control, and possibly a different temperature regulation strategy since steam rooms operate at lower temperatures (typically 40-50 degrees C) with near-100% humidity. If the CON4 has a dedicated steam generator output mode, it can control one. If it only has a heater output, it cannot properly control a steam generator. Verify the controller's specific feature set before connecting it to anything other than a standard sauna heater. Browse our full component catalog for compatible accessories.
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