It's Harvia's flagship sauna controller — a glass touch-screen panel with Wi-Fi that manages the heater, lighting and ventilation, and adapts to your heater's behaviour over time using onboard intelligence.

The Fenix builds a picture of how your particular sauna heats — how fast it climbs, how it holds temperature, how your room behaves — and adjusts its behaviour accordingly. In practice it means the sauna gets better at hitting your set temperature the more you use it, rather than running the same crude on-off cycle forever.

The Club, Spirit, Cilindro, Virta and Virta Pro series. It does not pair with the KIP series, which uses the CX170 instead — that's the most common mix-up, so check your heater before ordering.

No. If your heater has a built-in steamer you need a combi controller — the Fenix FX30C or Xenio CX30C. The FX45 has no humidity control and won't run a steamer.

Send us your heater's model and part number and we'll confirm before you spend anything. Harvia specifies a particular controller for each heater, and a mismatch either won't work or won't be covered under warranty.

It depends on your wiring configuration, and this catches people out. On single phase with one supply wire it handles up to 10.8 kW. On single phase with two supply wires it goes to 17 kW. On three phase, 15 kW. Tell your electrician which configuration you're using before they wire it.

Because a single supply wire limits how much current the unit can pass. Splitting the supply across two wires raises the ceiling considerably. It's the reason a heater like the Club K15G, which draws 61.7 amps single phase, is fed through two fuses rather than one.

Yes — this is one part number covering both. Your electrician configures it for your supply during installation.

The panel connects to your network, letting you control and monitor the sauna from a phone or tablet — check the temperature, adjust settings, or turn it off from anywhere.

Remote starting on any sauna heater is governed by safety requirements, because no app can verify nothing has been left on the stones. How that works in practice depends on which heater you pair it with — the Spirit series has hardware that permits genuine remote start, others require a physical confirmation first. Ask us about your specific combination before you buy.

No subscription applies to the hardware. You will need reliable Wi-Fi reaching the sauna, which is worth checking before you buy if it's an outbuilding at the end of the garden — a controller with no signal is just a wall panel.

The panel still works normally. Wi-Fi adds remote access; it isn't required for the sauna to operate.

Sauna lighting and ventilation, plus operating time and temperature — so one panel handles the whole room rather than you reaching for separate switches.

194°F (90°C), matching the heaters it controls.

60 minutes per session. That's a safety limit rather than a limitation — it means the sauna can't be left running indefinitely by accident.

On a wall, surface or flush mounted — and outside the sauna room. Unlike the Xenio CX45, this panel is not rated for installation inside the hot room.

Harvia rate this model for outside installation only. If you specifically want a panel inside the sauna room, the Xenio CX45 is rated for it — ask us and we'll compare the two for your layout.

Yes, within the cable limits between the panel, power unit and sensor. If you want it well away from the sauna, tell us the distance before you order so we can confirm it works or supply an extension.

3.4" wide × 1" deep × 4.4" high (86 × 25 × 111 mm) for the panel itself — the same footprint as the Xenio, so swapping between them doesn't mean patching a wall.

The control panel, temperature sensor, power unit, data cable, installation materials, the installation and operation manual, and the warranty.

It's the switching box between your electrical supply and the heater — the panel is just the interface. It mounts outside the sauna in a dry location with access for service. Plan its position with your electrician before anything gets wired; it's the piece people forget until install day.

Important one. If the sensor came with your heater, install it according to the heater's manual rather than the controller's. Harvia flag this specifically because the two manuals can give different instructions and the heater's takes precedence.

Yes. There's no plug — this is a permanent electrical installation and needs a licensed electrician.

The wiring must be done by a licensed electrician to local code. It's a mains-connected control for a high-load appliance, not a thermostat swap.

Yes, any licensed electrician can. Give them both manuals — the controller's and the heater's — before they start, and confirm the supply-wire configuration in advance since it determines the capacity.

No. Harvia sauna circuits should not be run on GFCI — it causes nuisance tripping and voids the warranty. If your electrician suggests one, point them at the installation manual first.

Only if your heater is on the compatible list — Club, Spirit, Cilindro, Virta or Virta Pro. Send us your heater's model and part number and we'll tell you straight whether this is the right one.

High-quality glass, which is the visible difference between the Fenix and the plastic-fronted Xenio panels. If the controller is going somewhere prominent, it looks and feels considerably better.

One year limited for consumer use, and one year limited for commercial use.

Yes — it carries an explicit commercial warranty. If it's going into a gym, spa or hotel, tell us; we handle commercial projects regularly and there may be considerations around session limits and access control worth discussing.

Yes — ETL listed. Your electrical inspector will want to see that listing.

Harvia design and manufacture in Finland.

Same capacity ceiling, same heater compatibility, same panel dimensions. The Fenix adds the glass screen and the adaptive learning; the Xenio is the established unit at a lower price and can be mounted inside the sauna room. If you want the nicer interface and the intelligence, take the Fenix; if you want the same capability for less, take the Xenio.

Honest answer: it depends what you value. Both run the same heaters to the same temperature. What you're paying for is the glass panel, the adaptive behaviour, and a more refined interface. If the controller sits somewhere you'll see it every day, that's a reasonable thing to spend on. If it's tucked in a utility corridor, probably not.

Compatibility and capacity. The FX45 adds the Virta Pro series to its list and handles larger heaters. If your heater is specified for the FX30, buy that one instead — the extra headroom here does nothing for you.

No. Heaters with onboard controls, like the Harvia KIP B series, are self-contained and don't take an external panel. This controller is for heaters that ship without controls.

Harvia offer a separate Wi-Fi remote control panel compatible with the Fenix range, which some owners fit as an additional or replacement interface. Ask us if you want a panel in more than one location.

By parcel carrier. Freight is calculated to your address — ask us for a delivered price, particularly if you're ordering it alongside a heater and stones.

Get in touch for current availability and a realistic date. We'd rather give you a real timeframe than a stock phrase.

Wipe the glass occasionally and keep it dry. There's nothing to service.

Call us. We handle warranty claims directly with Harvia rather than handing you a phone number. Note this is a serialised item, so keep your paperwork — the serial number matters for warranty claims.

Most buyers need this quoted with a heater and stones, and freight varies by address. Request pricing and you'll get one delivered figure for a complete working setup rather than a number you have to add to.

We're an authorized Harvia dealer, and on controllers specifically that's worth something — heater compatibility, supply configuration and cable runs are all easy to get wrong on paper. Send us your heater details and we'll confirm the correct controller before you spend anything, rather than after.

Please review our return policy at thesaunarepublic.com/policies/refund-policy. Because controllers are matched to specific heaters, confirm compatibility with us before ordering — it's a five-minute check that avoids a return.

Call (302) 273-0861 or email info@thesaunarepublic.com and we'll be glad to help.