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Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna
Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna

Finnmark FD-4 Trinity 2-Person Hybrid Indoor Infrared & Traditional Steam Sauna

by Finnmark
$7,795.00 - $7,795.00
$7,795.00
$7,795.00 - $7,795.00
$7,795.00

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✓ Lowest Price Guaranteed
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✓ Questions? Call an RFA Team Member: 1-855-864-6442

Heater does not come with power cord. Electrician required to install heater directly into its own circuit.
Shipping & Delivery Information

Free Delivery Damage Insurance Included With Purchase

 Curbside Delivery ships via Freight to the 48 contiguous states. The freight carrier will contact you 24 to 48 hours prior to delivery to set a delivery day and time Monday-Friday, with a 4-hour open window.

      They won’t deliver without speaking to you first. **Shipping times are only approximate, and can change depending on environmental conditions, transit issues, and carrier’s availability. Last minute appointments can occur, and it’s out of our hands since the delivery process is managed by the carrier’s. The sauna will be delivered in 1 box or more, depending on the model. All boxes will be strapped to a pallet. All saunas are delivered in a 53-foot semi-truck with a single driver, who will unload the pallet to your curbside or driveway only. Any delivery questions or issues (remote areas, long driveways, large and low hanging trees, apartment complex, stairs, etc.) should be addressed with us prior to shipping your sauna.

        Once the driver has unloaded the sauna, we ask that you immediately inspect the boxes for any damage. Please indicate any minor scratches, indentations, or scuff marks to the outside of the boxes on the delivery receipt. You do not need to open the boxes to inspect the sauna. The freight company will deliver your sauna to a carport or first-floor entryway. Please check the box dimensions and ensure it will fit through your doorway. Assembly on these saunas are surprisingly easy and can take between 30-45 minutes, depending on the sauna. Assembly instructions are included with the saunas.




Professional Installation Available

Rather not build it yourself? We partner with Pure Install for on-site sauna assembly.

  • Certified technicians assemble to the manufacturer's specification for your model
  • Function and safety check — temperature accuracy, responsiveness, calibration
  • Optional packaging, pallet and debris removal
  • One-year workmanship warranty on every new installation
  • Nationwide network, residential and commercial

See installation details and get started →

Warranty Information

In the USA the “lifetime” of an infrared sauna is considered 7 years. Many sauna brands offering a “lifetime warranty” know this and use it against you after 7 years of ownership. Your Finnmark Design’s sauna comes with a 10-year warranty, giving you piece of mind that after 7 years you are still covered.

Unconditional Lifetime Warranty

Spectrum Plus™  infrared heaters (UL Listed) have an estimated operational life of 40,000 hours and our carbon 360 heaters have an estimated operational life of 30,000 hours. Using your sauna 5 times per week your Spectrum heaters can last up to 130 years. 

Our Spectrum Plus™ Incoloy heaters have a unconditional lifetime warranty. No other sauna brand is that confident in their heating elements. 

10-Year Sauna Warranty

Your sauna is an asset to your health, protect it wisely.  Finnmark Designs doesn’t offer a questionable warranty like many of our competitors.  You receive an upfront warranty with terms that are easy to understand.  

Download Warranty

Indoor Infrared & Traditional Sauna

Finnmark FD-4 Trinity 2-Person Infrared & Steam Sauna

The FD-4 Trinity is the smallest cabin Finnmark build with a rock heater inside it. A Harvia Vega Compact 1900 is included along with a box of Harvia AC3000 stones, so the same two-person cabin runs infrared at 170°F or traditional heat with steam at 190°F. Exterior is 48 inches square and 83 inches tall; interior is 44.25 wide by 45.5 deep by 75.5 high, for 86 cubic feet.

Three heat sources share the cabin. Spectrum Plus dual wave infrared panels line the walls and the underside of the bench, the Harvia sits on the front interior wall, and a 192-diode medical grade LED panel delivers Finnmark's Spectrum Red Light™ Therapy at 650nm. A V2 LCD Controller, a 5-inch touchscreen with Bluetooth, is included.

Capacity
2 Bathers
86 cu ft interior
Exterior
48" × 48"
83" tall
Interior
44.25" × 45.5"
75.5" tall
Max Temperature
190°F
170°F on infrared
Harvia Vega Compact 1900 included 29 lbs of AC3000 stones 192-diode red light panel 5-inch V2 LCD touchscreen
Finnmark FD-4 Trinity sauna installed in a bathroom, exterior view

The Build

Three Heat Sources In A 48-Inch Square Cabin

Rock heat, infrared and red light, in one 86 cubic foot room. Here is each piece and what Finnmark specify for it.

🪨
Harvia Vega Compact 1900
A 1.9kW electric rock heater, 120V single phase, 15.9 nominal amps, weighing 15.4 lbs, rated by Harvia for rooms of 70 to 106 adjusted cubic feet. The FD-4's 86 cubic feet sits inside that band. One box of Harvia AC3000 stones, 0 to 10cm, ships with it.
Included · 29 lbs Of Stones
🔥
Spectrum Plus™ Infrared Panels
Three Spectrum Plus dual wave panels on the back wall, one under the bench and two on each side wall. Finnmark specify UL Listed incoloy short-wave elements at .99 emissivity with a 40,000-hour rated life.
Lifetime Heater Warranty
🔴
Spectrum Red Light™ Therapy
A 192-diode medical grade LED panel running at 650nm, mounted in the cabin ceiling. Chromotherapy lighting runs alongside it, so the same cabin can be lit for red light work or for colour.
192 Diodes At 650nm
📱
V2 LCD Controller
Finnmark include a V2 LCD Controller with the FD-4: a 5-inch touchscreen with Bluetooth.
5" Touchscreen · Bluetooth

Why Athletes Choose This

Eight Things The FD-4 Gives You

Finnmark publish their own claims for infrared and red light therapy, with an FDA disclaimer beside them; those are Finnmark's to stand behind. The eight cards below are specification and included equipment.

🪨
Harvia rock heater included
Vega Compact 1900
💨
190°F with steam
Traditional Mode
🔴
192-diode red light panel
650nm Spectrum Red Light™
📱
5-inch touchscreen control
V2 LCD With Bluetooth
⚖️
29 lbs of AC3000 stones
Shipped With The Heater
🔥
Full spectrum infrared
Spectrum Plus Panels
👥
Seats two bathers
86 Cubic Feet
🛡️
Lifetime heater warranty
Spectrum Plus™ Panels

Rocks, Panels And Red Light

A Closer Look At The FD-4 Trinity

Front view into the Finnmark FD-4 Trinity with steam rising from the Harvia rock heater
Traditional Heat

Rocks And Steam, Included

Pour water on the stones and the FD-4 becomes a traditional sauna at up to 190°F, twenty degrees above what the infrared side reaches. The Harvia Vega Compact 1900 does that work: 1.9kW, electric, 120V single phase, 15.9 nominal amps, 15.4 lbs, and rated by Harvia for 70 to 106 adjusted cubic feet. One box of Harvia AC3000 stones, sized 0 to 10cm and weighing 29 lbs, comes with it.

  • Harvia Vega Compact 1900 included, no separate heater purchase
  • 1.9kW, 120V, single phase, 15.9 nominal amps
  • Rated for rooms of 70 to 106 adjusted cubic feet
  • 29 lbs of Harvia AC3000 stones, 0 to 10cm
  • 190°F maximum in traditional mode
Heater Included 190°F
Finnmark layout diagram for the FD-4 Trinity labelling the Spectrum, Spectrum Plus and Harvia heater positions
Cabin Layout

Where The Three Heat Sources Sit

Finnmark's layout diagram labels every position. Three Spectrum Plus dual wave panels are set into the back wall, one goes under the bench, and two are fitted to each side wall. The Harvia occupies the front interior wall. Infrared comes off three surfaces and the bench, and the rock heat comes from the wall you walk in through.

  • Three Spectrum Plus dual wave panels on the back wall
  • One Spectrum Plus panel under the bench
  • Two panels on each side wall
  • Harvia Vega on the front interior wall
Infrared + Traditional UL Listed Heaters
Interior of the Finnmark FD-4 Trinity with the ceiling red light therapy panel and the wall infrared panels lit
Red Light

A 192-Diode Panel Overhead

The third element in the Trinity is Finnmark's Spectrum Red Light™ Therapy: a medical grade LED panel carrying 192 diodes at 650nm, set into the ceiling above the bench. Chromotherapy lighting is fitted alongside it, so the cabin can be run under red light or under colour. The cabin ships with the V2 LCD touchscreen.

  • 192-diode medical grade LED panel
  • 650nm wavelength
  • Chromotherapy lighting included
  • V2 LCD touchscreen with Bluetooth included
Spectrum Red Light™ 650nm
Overhead view into the Finnmark FD-4 Trinity showing the bench layout and the Harvia heater
Interior

Eighty-Six Cubic Feet For Two

From above you can see how the space is divided: bench along one side, Harvia against the front wall, on a 44.25 by 45.5 inch interior floor. Height is 75.5 inches, five and a half more than any of the infrared-only cabins give you. The door is 23.625 by 67.875 inches in 8mm glass with a gasket.

  • Interior 44.25" W × 45.5" D × 75.5" H
  • 86 cubic feet of room volume
  • Rated for two bathers
  • 8mm glass door with gasket, 23.625" × 67.875"
Seats 2 8mm Gasketed Glass

The Finnmark Indoor Lineup

The Smaller Of The Two Trinity Hybrids

Three of Finnmark's five indoor cabins are infrared only. Two are Trinity hybrids with a Harvia rock heater included, and the FD-4 is the smaller of those two. It is the model to look at when you want steam on the stones without giving up a 48-inch square footprint or committing to the FD-5's 240V install.

Finnmark FD-1 one-person infrared sauna, three-quarter exterior view
FD-1 — 1 Person
The smallest cabin in the line, 38 inches square, and it runs off a standard household outlet.
Seats 1 bather 38 × 38 × 78 in exterior 32 × 34 × 70 in interior 120V 15A, NEMA 5-15P
Shop the FD-1
Finnmark FD-2 two-person infrared sauna, three-quarter exterior view
FD-2 — 2 Person
Finnmark's best seller, and the only model in the line with a published heat-up test.
Seats 2 bathers 48 × 44 × 78 in exterior 43 × 40 × 70 in interior 54 minutes to 170°F
Shop the FD-2
Finnmark FD-3 three to four person infrared sauna, three-quarter exterior view
FD-3 — 3–4 Person
The size step in the infrared cabins: 67 inches of interior width, on a 240V circuit.
Seats 3–4 bathers 72 × 46 × 78 in exterior 67 × 41 × 70 in interior 240V 15A, NEMA 6-15P
Shop the FD-3
You're Here
Finnmark FD-4 Trinity sauna cabin beside a glass wall, three-quarter exterior view
FD-4 Trinity — 2 Person
The way into rocks and steam. A Harvia Vega Compact 1900 ships with the sauna.
Seats 2 bathers 48 × 48 × 83 in exterior 44.25 × 45.5 × 75.5 in interior 1.9kW Harvia included
Currently viewing
Finnmark FD-5 Trinity XL sauna cabin, three-quarter exterior view
FD-5 Trinity XL — 4 Person
The largest indoor cabin at 130 cubic feet, with a 4.5kW Harvia included.
Seats 4 bathers 75 × 64 × 83 in exterior 71 × 57.5 × 75.5 in interior 4.5kW Harvia included
Shop the FD-5

Questions

Frequently Asked Questions

Yes. The Harvia Vega Compact 1900 is included — 1.9kW, electric, 120V single phase, 15.9 nominal amps, 15.4 lbs, rated by Harvia for rooms of 70 to 106 adjusted cubic feet. One box of Harvia AC3000 stones, 0 to 10cm and weighing 29 lbs, ships with it. Nothing about the rock heater is a separate purchase.
The infrared side runs on 120V, 1,750 watts, NEMA 5-15P. The Harvia Vega Compact 1900 is also 120V, single phase, at 15.9 nominal amps. Finnmark frame the FD-4 as a unit that runs on standard 120V across two circuits. One thing to plan for, as stated in the buy box on this page: "Heater does not come with power cord. Electrician required to install heater directly into its own circuit." Book that before the sauna arrives.
Two. The interior measures 44.25" W × 45.5" D × 75.5" H for 86 cubic feet. That volume matters more than usual on this model, because the included Harvia is rated for 70 to 106 adjusted cubic feet and the cabin sits inside that range.
170°F on infrared, 190°F on traditional. The twenty-degree difference is the Harvia's contribution, and the traditional mode is the one that lets you throw water on the stones for steam.
Finnmark's name for the LED panel fitted in the FD-4's ceiling: 192 medical grade diodes running at 650nm. Chromotherapy lighting is installed alongside it. A V2 LCD touchscreen with Bluetooth is included. Any therapeutic claim for red light on this page is Finnmark's; they publish their own FDA disclaimer.
Through a V2 LCD Controller, a 5-inch touchscreen with Bluetooth, included with the sauna.
A Thermo-Aspen exterior with a Western Canadian Cedar interior. Finnmark's Thermal Plus™ process treats the aspen with heat and steam and no chemicals, and their claim is that it will not rot, warp, decay or chip. They describe the cedar as naturally antimicrobial, resisting mold, bacteria and fungus.
The exterior is 48" W × 48" D × 83" H. Assembled product weight is 437 lbs, shipping weight is 485 lbs including a 48 lb pallet. The 83-inch height is the number worth checking against a basement ceiling.
Free curbside delivery via freight to the 48 contiguous states, with free delivery damage insurance included. The freight carrier contacts you 24 to 48 hours ahead to set a day and time Monday through Friday inside a 4-hour window, and will not deliver without speaking to you first. The sauna arrives strapped to a pallet on a 53-foot semi-truck with a single driver, who unloads to your curbside or driveway only. Raise anything unusual about your access — long driveway, low branches, stairs, apartment complex — with us before the sauna ships. When the driver unloads, inspect the boxes and note any scratches, dents, or scuff marks on the delivery receipt. You do not need to open the boxes to do that.
Finnmark cover the sauna with a 10-year warranty and the Spectrum Plus™ incoloy infrared heaters with an unconditional lifetime warranty. Finnmark's own framing for the ten-year term is worth repeating: in the USA the working lifetime of an infrared sauna is considered seven years, so a ten-year term still covers you past that point. They state operational life at 40,000 hours for the Spectrum Plus heaters. Full terms are in the Warranty tab. The sauna is ETL certified and made by Finnmark Designs, based in Wheeling, Illinois.
  • External Materials: Thermo-Aspen
  • Interior Materials: Western Canadian Cedar
  • Volts: 120
  • Watts: 1750
  • Amperage: 15/20
  • Plug Type: NEMA 5-15P
  • Outlet: Standard 120v 15a
  • Maximum Temperature: IR 170F - Traditional 190F
  • Interior Dimensions: 44.25"W x 45.5"D x 75.5"H
  • Exterior Dimensions: 48"W x 48"D x 83"H
  • Room Volume: 86 cu. ft.
  • Door Dimensions: 23.625"W x 67.875"H
  • Door Handle Dimensions: 1.5"W x 13.25"H
  • Glass Thickness: 8mm W/Gasket
  • Product Weight: 437 lbs
  • Shipping Dimensions: 36"W x 80"D
  • Shipping Weight: 485 lbs W/48 lb Pallet

Vega Compact 1900 (Heater does not come with power cord. Electrician required to install heater directly into its own circuit.)

  • Kilowatt Rating (KW): 1.9kW
  • Primary Fuel: Electric
  • Minimum Adjusted Cubic Feet: 70
  • Maximum Adjusted Cubic Feet: 106
  • Voltage: 120V
  • Phase: 1PH
  • Nominal Amps: 15.9 Amps
  • Heater Weight: 15.4 lbs
  • Shipping Weight with Sauna Stones: 59.4 lbs
  • Width In Inches: 11" (279mm)
  • Depth In Inches: 11" (279mm)
  • Height In Inches: 21" (533mm)
  • Sauna Power Requirements: 240V for sauna heater. 120V for interior/exterior lights.
  • Bottom Panel
  • Top Panel
  • Back Panel
  • Front Panel
  • Left Panel
  • Right Panel
  • Glass Door
  • Bench Support
  • Bench Top
  • Heater Cable
  • Floor Cable
  • Screws
  • Power Supply Unit
  • Power Cable
  • Interior Heater Connections with Wood Cover
  • Door Handle (2 Screws)
  • Infrared Sauna Heater Panels
  • Harvia Vega Compact 1900 Sauna Heater
  • 1 Box of the Harvia AC3000 0-10cm sauna stones (29 lbs) (Please note that each natural stone is unique in shape and size. We recommend purchasing an additional box of sauna stones to allow you to choose the highest quality of stone for fit, form, and function (Additional freight charges will apply).)
  • Medical Grade LED Red light therapy with 650nm plus color chromotherapy
  • V2 LCD Controller 5" Touchscreen with Bluetooth
  • ETL Certification
  • Limited Warranty

In the USA the “lifetime” of an infrared sauna is considered 7 years. Many sauna brands offering a “lifetime warranty” know this and use it against you after 7 years of ownership. Your Finnmark Design’s sauna comes with a 10-year warranty, giving you piece of mind that after 7 years you are still covered.

Unconditional Lifetime Warranty

Spectrum Plus™  infrared heaters (UL Listed) have an estimated operational life of 40,000 hours and our carbon 360 heaters have an estimated operational life of 30,000 hours. Using your sauna 5 times per week your Spectrum heaters can last up to 130 years. 

Our Spectrum Plus™ Incoloy heaters have a unconditional lifetime warranty. No other sauna brand is that confident in their heating elements. 

10-Year Sauna Warranty

Your sauna is an asset to your health, protect it wisely.  Finnmark Designs doesn’t offer a questionable warranty like many of our competitors.  You receive an upfront warranty with terms that are easy to understand.  

Download Warranty

Free Delivery Damage Insurance Included With Purchase

 Curbside Delivery ships via Freight to the 48 contiguous states. The freight carrier will contact you 24 to 48 hours prior to delivery to set a delivery day and time Monday-Friday, with a 4-hour open window.

      They won’t deliver without speaking to you first. **Shipping times are only approximate, and can change depending on environmental conditions, transit issues, and carrier’s availability. Last minute appointments can occur, and it’s out of our hands since the delivery process is managed by the carrier’s. The sauna will be delivered in 1 box or more, depending on the model. All boxes will be strapped to a pallet. All saunas are delivered in a 53-foot semi-truck with a single driver, who will unload the pallet to your curbside or driveway only. Any delivery questions or issues (remote areas, long driveways, large and low hanging trees, apartment complex, stairs, etc.) should be addressed with us prior to shipping your sauna.

        Once the driver has unloaded the sauna, we ask that you immediately inspect the boxes for any damage. Please indicate any minor scratches, indentations, or scuff marks to the outside of the boxes on the delivery receipt. You do not need to open the boxes to inspect the sauna. The freight company will deliver your sauna to a carport or first-floor entryway. Please check the box dimensions and ensure it will fit through your doorway. Assembly on these saunas are surprisingly easy and can take between 30-45 minutes, depending on the sauna. Assembly instructions are included with the saunas.