Finnmark FD-5 Trinity 4-Person Hybrid Indoor Infrared & Traditional Steam Sauna
The Finnmark FD-5 Trinity XL is a 4-person hybrid sauna that puts infrared heat, a traditional Harvia rock heater for steam, and red light therapy in one cabin. UL-listed Spectrum Plus™ infrared heaters take the cabin up to 170°F, while the 4.5 kW Harvia KIP Series B heater reaches up to 190°F when you pour water over the stones. The cabin is built with a Thermal Plus™ European Aspen exterior and a clear A-grade Western Canadian Cedar interior with a two-tier bench.
Infrared, steam, and red light in one cabin
Use the infrared side for a lower-temperature session, switch to the Harvia heater for a traditional sauna with steam, or use both. The Spectrum Plus™ dual-wave heaters are UL-listed Incoloy elements that produce mid and far infrared, carry 0.99 emissivity, and are rated for about 40,000 hours. A Spectrum Red Light panel with 192 LED diodes at 650nm adds red light therapy, with chromotherapy color lighting alongside it.
Thermal Aspen outside, cedar inside
The exterior is Thermal Plus™ European Aspen, a wood that is heat and steam treated with no chemicals and is made to resist rot, warping, decay, and chipping. Inside, the walls and the two-tier bench are clear A-grade Western Canadian Cedar, which is naturally antimicrobial. Tongue and groove, double-walled construction with non-toxic wool insulation and an 8mm tempered glass door with a gasket help keep the heat inside the cabin.
Harvia KIP Series B 4.5 kW heater
The traditional side runs on a Harvia KIP Series B (KIP45B), a 4.5 kW, 240V wall-mounted stainless steel heater with built-in controls, UL listed and made in Finland. It is rated for rooms of 100 to 210 cubic feet. One 44 lb box of Harvia AC3000 stones is included; the heater needs at least 50 lbs, so an extra box is recommended. The heater runs on its own dedicated 240V circuit, installed by a licensed electrician.
Controls and certifications
The V2 LCD controller puts a 5" touchscreen inside the cabin for temperature, lighting, and music, with Bluetooth audio through 6" marine-grade HiFi speakers and remote start from your phone. The infrared side plugs into a 240V / 15A outlet (NEMA 6-15P) on a dedicated circuit. The cabin is ETL certified, the Spectrum Plus™ heaters are UL listed, and EMF levels are third-party tested. You can review the test log and certificates in the documents below.
Bottom, top, back, front, left and right panels
8mm tempered glass door
Bench support and bench top
Spectrum Plus™ infrared heater panels
Harvia KIP Series B 4.5 kW heater
1 box Harvia AC3000 stones (44 lbs)
LED red light panel (650nm) with chromotherapy
V2 LCD controller with Bluetooth audio
Interior heater connections with wood cover
Heater cable and floor cable
Power supply unit and power cable
Door handle (with 2 screws)
Assembly screws
ETL certification and limited warranty
Infrared and steam for 4
Spectrum Plus™ infrared heaters and a 4.5 kW Harvia KIP rock heater share one 4-person cabin. Use either one, or both together.
Spectrum Plus™ heaters
UL-listed Incoloy dual-wave heaters produce mid and far infrared, carry 0.99 emissivity, and are rated for about 40,000 hours.
Harvia KIP Series B
A 4.5 kW, 240V stainless steel heater made in Finland, rated for rooms of 100 to 210 cu. ft. Pour water on the stones for steam at up to 190°F.
Red light therapy
A 192-diode, 650nm Spectrum Red Light panel with chromotherapy color lighting alongside it.
Thermal Aspen and cedar
Chemical-free Thermal Plus™ Aspen exterior with an antimicrobial Western Canadian Cedar interior and two-tier bench.
UL listed & ETL certified
Spectrum Plus™ and Harvia heaters are UL listed and the cabin is ETL certified. EMF levels are third-party tested; documents are below.
Lifetime
Spectrum Plus™ Heaters
Warranty basics
The Finnmark FD-5 Trinity XL comes with a 10-year Finnmark Designs sauna warranty, plus an unconditional lifetime warranty on the Spectrum Plus™ Incoloy heaters. The Harvia KIP heater carries its own 2-year consumer warranty.
Coverage conditions
The sauna must be installed per the instructions and properly maintained. The Harvia heater warranty requires proper care of the sauna stones. Using the sauna outdoors without an outdoor cover voids the warranty.
Full terms
We are an authorized Finnmark Designs dealer. See the official warranty document above for full terms, exclusions, and claim procedures.
