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Finnmark FD-4 Trinity 2-Person Hybrid Infrared & Steam Sauna | FD-KN004

Finnmark FD-4 Trinity 2-Person Hybrid Infrared & Steam Sauna | FD-KN004

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The ultimate sauna experience is here.  The FD-4 Trinity™ 3-IN-ONE Hybrid Sauna combines all the benefits of infrared, steam and red light therapy all in one beautiful sauna cabin. UL listed Spectrum Plus™ infrared heaters combined with a Harvia™ traditional heater all while soaking in red light therapy. 

Why settle when you can experience it all? 

Sauna Features

  • Spectrum Plus™ Infrared Heaters - UL Listed short wave infrared heaters for deep penetrating heat, up to 25x more than standard carbon panel heaters
  • Red Light + Chromotherapy Panel - 192-diode LED system delivers 650nm red light paired with mood-boosting chromotherapy
  • Cedar Interior & Thermal Plus™ Aspen Exterior - Antimicrobial Western Canadian cedar resists mold and bacteria; aspen exterior is rot-proof and built-to-last
  • True 3-in-1 Sauna - Combines full spectrum infrared, traditional steam, and red light therapy in one powerful setup
  • Smart Controls & Premium Audio - Built-in LCD WiFi touchscreen controller, Bluetooth, and 6" HiFi speakers for a fully immersive experience
  • Spacious, Low EMF Design - Extra large two-tier bench system and lab-tested low EMF output ensures both comfort and safety

Heater Features

Harvia Vega Compact 1900

  • Wall-mounted design
  • Stainless steel construction 
  • 1.9kW
  • For sauna rooms from 70 to 106 cu. ft.
  • Built-in controls
  • Ergonomic operating switches (can be installed on the right or left side of the heater)
  • Designed, engineered, and made in Finland
  • Dimensions: 11"W (279mm) x 11"D (279mm) x 21" (533mm)
  • 2-Year Warranty (Consumer use)

Specifications

Product Spec Sheet

Maximum Temperature
Infrared: 170°F
Traditional: 190°F

Exterior Dimensions
48"W x 48"D x 83"H

Interior Dimensions
44.25"W x 45.5"D x 75.5"H

Electrical Requirements
FD-4 Trinity Sauna: 120V, 1750W, 15A, NEMA 5-15P plug
Harvia Vega Compact Heater: 120V, 1900W, 20A (Installation by a licensed electrician required)

IR Watts 
1750W

Wood Type
Thermal Plus™ European Aspen Exterior
Clear "A" Grade Western Canadian Red Cedar Interior

Product Weight
437 lbs

Shipping Weight
618 lbs

Shipping Dimensions
80"W x 40"D x 58"H

What's Included

  • Infrared Sauna Heater Panels
  • Harvia Vega Compact 1900 Sauna Heater
  • 1 Box of the Harvia AC3000 0-10cm Sauna Stones (29 lbs)
  • Bench: Support Frame & Seat Top
  • Spectrum LED Near Infrared Ceiling Lights + Red Light Therapy
  • Controller 2.0, Built-In LCD Touchscreen Control Panel with Bluetooth Audio
  • Interior Heater Connections with Wood Cover
  • Power Supply Unit + Power & Heater Cables
  • Screws & Installation Hardware
  • ETL Certification
  • 10-Year Limited Warranty
  • Unlimited Lifetime Spectrum Plus
  • 2-Year Harvia Traditional Heater Warranty

Manuals & Certifications

Owner's Manual

Harvia Heater Manual

Harvia Heater Specifications

Dimensions Diagram

ETL Certification

EMF Test

4.9/5 Customer Rating

Rated for comfort, quality, and peace of mind.

Our customers consistently give us 4.9 out of 5.

Authorized Dealer • Full Warranty

Official dealer pricing with manufacturer-backed warranties.

Easy Financing Options

Enjoy now, pay later.

Flexible payments available — rates from 0% APR with Shop Pay.

Excellent Customer Service

Got questions?

Contact us via live chat, phone, or email (M-F 9am-5pm EST).

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3-in-1 Hybrid Sauna: Infrared, Harvia Steam & Advanced Red Light

3-in-1 Hybrid Sauna: Infrared, Harvia Steam & Advanced Red Light

Why compromise when you can have it all? This revolutionary 3-in-1 sauna puts you in complete control of your wellness, combining legendary sauna traditions with modern technology for an unparalleled home spa experience.

Spectrum Plus™ Infrared

Tested and approved for safe use alongside traditional steam sauna stoves, meeting stringent safety standards such as those set by Underwriter Laboratories. Designed with advanced short-wave far-infrared technology, they deliver deeper muscle and joint penetration and can stimulate up to 25x more sweat compared to standard carbon panel heaters. Ideal for those seeking enhanced detox, circulation, and relaxation—all in less time.

Harvia™ Vega Electric Heater

Harvia™ Vega Electric Heater

Take your infrared experience to the next level and combine your sauna session with a Harvia™ traditional electric heater.  Splash some water on the rocks and enjoy the many benefits of steam. 

Spectrum Red Light™ Therapy

Spectrum Red Light™ Therapy

Premium LED panel capable of producing highly beneficial 650nm of red light therapy combined with chromotherapy for those days you need a little love.