{"product_id":"saunalife-model-s4-wood-fired-hot-tub","title":"SaunaLife Soak-Series Model S4 | Wood-Fired Hot Tub | No Electricity Required | 304 Gallons | Heats in Under 2 Hours | 304 Stainless Steel Stove | Black Thermo-Spruce | Fully Assembled | Up to 6 Bathers","description":"\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003e\u003cstrong\u003e304 Gallons. Under Two Hours. Zero Electricity. The Right-Sized Wood-Fired Hot Tub for Most Backyards.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003eThe SaunaLife Soak-Series Model S4 Wood-Fired Hot Tub delivers the same off-grid, eco-friendly wood-burning experience as SaunaLife's larger S6 models in a more accessible 79-inch diameter footprint — holding over 304 gallons of water and comfortably seating up to 6 bathers. Constructed from Thermo-Spruce, which lasts up to twice as long as cedar with superior thermal resistance to retain heat, the S4's 1.65-inch thick tub surround is finished in black for a sleek, modern exterior. Inside, a thick, dark grey contoured fiberglass lining provides enhanced bather comfort against the tub walls. The stainless steel wood-burning heater uses dual heat compartments for unmatched efficiency, bringing water to ideal soaking temperatures — up to 106°F — in under two hours, with a polished stainless steel chimney and protective cap for safe, rapid heat-up. The S4 arrives fully assembled, requires no electrical connection whatsoever, and includes matching Thermo-Spruce steps for easy access, an extra-thick steel-reinforced foam cover with a dark grey marine-grade vinyl exterior that folds for easy removal and storage, and an integrated drainage tap for simple maintenance. Just position it, fill it, light the stove, and soak — luxury wood-fired bathing without a single utility bill.\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003e\u003cstrong\u003eKey Specifications\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul class=\"[li_\u0026amp;]:mb-0 [li_\u0026amp;]:mt-1 [li_\u0026amp;]:gap-1 [\u0026amp;:not(:last-child)_ul]:pb-1 [\u0026amp;:not(:last-child)_ol]:pb-1 list-disc flex flex-col gap-1 pl-8 mb-3\"\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eSeries: Soak-Series\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eModel: S4\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eType: Wood-burning outdoor hot tub — no electricity required\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eCapacity: Up to 6 bathers\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eWater Capacity: 304 gallons\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eExterior Dimensions: 79 in diameter × 37 in high\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eInterior Dimensions: 71 in diameter × 33 in deep\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eTub Surround: 1.65 in thick Thermo-Spruce, painted black\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eInterior Lining: Thick, dark grey contoured fiberglass — enhanced bather comfort\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eHeater: 304 stainless steel wood-burning heater — dual heat compartments\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eHeat-Up Time: Under 2 hours\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eMaximum Temperature: 106°F\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eChimney: Polished stainless steel with protective cap\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eStove Dimensions: 19.8 in D × 11.8 in W × 13.1 in H\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eChimney Dimensions: 4.7 in diameter × 95 in H\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eMaximum Wood Length: 16 in\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eAccess: Matching Thermo-Spruce wood steps\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eCover: Extra-thick steel-reinforced foam, folding design, dark grey marine-grade vinyl exterior\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eDrainage: Integrated drainage tap\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eProduct Weight (filled): 3,064 lbs\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eShipping Dimensions: 91 in L × 46 in W × 87 in H\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eShipping Weight: 595 lbs\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eAssembly: Fully assembled — ready to fill and fire\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eElectrical Requirement: None — fully off-grid compatible\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eUse: Outdoor\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eWarranty: SaunaLife Limited Lifetime Warranty (residential use)\u003c\/li\u003e\n\u003cli class=\"font-claude-response-body whitespace-normal break-words pl-2\"\u003eOrigin: Designed by SaunaLife, handcrafted in Northern Europe\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003e\u003cstrong\u003eWho This Is For\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003eThe S4 is built for homeowners who want the SaunaLife wood-fired hot tub experience — no electricity, no utility hookup, fully assembled on arrival — in a more compact 79-inch footprint than the flagship S6 models. It suits families and small groups of up to 6, buyers with limited patio or deck space who still want a genuine soaking capacity of 304 gallons, off-grid and rural property owners, and design-conscious homeowners drawn to the modern black Thermo-Spruce exterior paired with dark grey fiberglass and vinyl detailing.\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003e\u003cstrong\u003eFrequently Asked Questions\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003e\u003cem\u003eQ: How does the S4 compare to the S6B and S6N?\u003c\/em\u003e\u003cbr\u003eA: The S4 is the more compact model in the Soak-Series — 79-inch diameter and 304-gallon capacity versus the S6B\/S6N's 89-inch diameter and 436+ gallon capacity, seating up to 6 bathers versus 7. The S4's surround is painted black as standard, while the S6B offers a black finish and the S6N offers a natural Thermo-Spruce finish as separate model options. All three share the same dual-chamber stainless steel wood-burning heater technology, no-electricity operation, and fully assembled delivery.\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003e\u003cem\u003eQ: Does it really require zero electricity?\u003c\/em\u003e\u003cbr\u003eA: Yes — the S4 is entirely wood-fired, with the 304 stainless steel heater's dual heat compartments driving water circulation through natural convection. No pumps, motors, or electrical connections are needed, making it fully compatible with off-grid properties and locations without accessible electrical infrastructure.\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003e\u003cem\u003eQ: How long does it take to heat up, and what temperature can it reach?\u003c\/em\u003e\u003cbr\u003eA: The S4's dual-compartment stainless steel heater brings water to ideal soaking temperature in under 2 hours, with a maximum temperature of 106°F. The polished stainless steel chimney with protective cap ensures safe, efficient combustion and rapid heat response.\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003e\u003cem\u003eQ: What is included with the S4?\u003c\/em\u003e\u003cbr\u003eA: The S4 arrives fully assembled and includes matching Thermo-Spruce steps for access, an extra-thick steel-reinforced foam cover with dark grey marine-grade vinyl exterior (folds for easy removal and storage), integrated drainage with a tap, a polished stainless steel chimney, and a chimney cap.\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003e\u003cem\u003eQ: What foundation does the S4 require?\u003c\/em\u003e\u003cbr\u003eA: A flat, level, stable surface capable of supporting the tub's filled weight of approximately 3,064 lbs. Concrete pads, compacted gravel, or reinforced decking are appropriate foundation options. The surface must be completely level for proper stove operation and even weight distribution.\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\"\u003e\u003cem\u003eQ: Can the S4 be paired with a sauna for contrast therapy?\u003c\/em\u003e\u003cbr\u003eA: Yes — the S4 is an ideal companion to any sauna or barrel sauna in the SaunaLife lineup, or to the RAIN-Series R3 outdoor shower for a complete rinse-and-soak circuit. Alternating between sauna heat and the S4's wood-fired warm soak (or following with a cold plunge) creates a full contrast therapy routine using entirely off-grid equipment.\u003c\/p\u003e","brand":"The Sauna Solution LLC","offers":[{"title":"BLACK","offer_id":45036305645637,"sku":"SL-MODELS4B","price":5990.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0665\/0747\/2965\/files\/saunalife-model-s4-wood-fired-hot-tub-sauna-heater-supply-544714.jpg?v=1779294912","url":"https:\/\/homeupgradedirect.com\/products\/saunalife-model-s4-wood-fired-hot-tub","provider":"HomeUpgradeDirect","version":"1.0","type":"link"}