Hybrid saunas promise both experiences in one cabin: infrared panels for long, gentle sessions and a traditional heater for heat and steam. The Finnmark FD-5 Trinity XL is the largest Trinity model and our Best Overall pick for home saunas.
This article goes deep on that one model, for buyers who already have it on a shortlist. For the general buying process, see the home sauna buying guide.
Short answer: the FD-5 is a 4-person hybrid with a 2,700W infrared array and a 4.5kW Harvia traditional heater. It suits households who want both heat types and have, or can add, 240V service. Confirm the wiring details with the dealer first.
The specs that matter
| Finnmark FD-5 Trinity XL | |
|---|---|
| Price (Select Saunas, Oct. 1, 2026) | $8,995 (compare-at $11,693) |
| Capacity | 4 people |
| Infrared | Spectrum Plus array, 2,700W, up to 170°F |
| Traditional | Harvia KIP45B, 4.5kW, up to 190°F |
| Exterior | 75 in. W × 64 in. D × 83 in. H |
| Interior | 71 × 57.5 × 75.5 in. |
| Materials | Western Canadian cedar interior, Thermo-Aspen exterior |
| Stones | At least 50 lbs (not included) |
| Weight | 575 lbs; 840 lbs shipping (Select Saunas listing) |
Is the heater sized right?
Yes, by the numbers. The interior works out to about 178 cubic feet (71 × 57.5 × 75.5 inches). Select Saunas’ listing rates the KIP45B for rooms of 100–210 cubic feet, so the cabin sits comfortably inside that range.
The wiring question
Here’s what the spec sheet won’t tell you clearly: the listings don’t fully agree on power. Select Saunas’ listing gives 240V for the cabin, lists the amperage as “15 | TBD,” and names a NEMA 5-15P plug, which is a standard 120V plug type. Another dealer listing gives 240V at 18.8A.
Treat this as a 240V project until the dealer confirms otherwise in writing, and get that confirmation before your electrician quotes. A 2026 installer guide puts an indoor 240V circuit at about $450–900.
Warranty
The Sauna Place’s dealer listing states a 10-year warranty on the entire sauna and a lifetime warranty on the Spectrum Plus infrared heaters. Select Saunas’ listing, which is where our link goes, states a 2-year consumer warranty on the traditional heater. Ask for the warranty document before you buy so you know exactly what’s covered.
Who it suits
You get the most flexibility of any cabin in our home sauna comparison: four seats, both heat types, and independent control of each. You give up the easy install of smaller hybrids like the FD-4, which plugs into 120V, and you pay about $2,000 more than the traditional-only Golden Designs Forssa.
My rule of thumb: if two or more people will use it and you want steam some days and gentle infrared on others, the FD-5 is worth the extra electrical work. If it’s mostly you, the smaller FD-4 is the simpler buy.
See how it stacks up against the other three picks in our home sauna comparison, or compare infrared-only options in the infrared sauna buying guide.
Bottom line: a strong 4-person hybrid with heaters matched to its size. Get the wiring and warranty confirmed in writing, and it’s an easy recommendation.
Sources
- Select Saunas, Finnmark FD-5 Trinity XL listing (price, heaters, dimensions, stones, weight, power, heater warranty), checked October 1, 2026: selectsaunas.com
- The Sauna Place, Finnmark FD-5 Trinity XL dealer listing (warranty terms), checked September 2026
- Haven of Heat, “Typical Cost to Have a Sauna Installed,” 2026: havenofheat.com
