Free Delivery · 1–2 Yr Warranty · After-sales Support
The Black Prism is our premium sauna heater, featuring a sleek tower design with clean geometric lines. This sophisticated heater combines modern aesthetics with exceptional heating performance, making it the centrepiece of any high-end sauna installation.
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Standing 80.5cm tall with a compact 31 x 31cm footprint, the Prism heater fits elegantly into corner installations whilst its vertical profile creates visual impact. The enclosed design provides a clean, minimalist appearance, whilst the internal stone chamber delivers high-quality steam production.
Built with heavier-gauge construction (20.5kg without stones), the Prism is engineered for demanding use and long service life. The matte black finish complements contemporary sauna interiors, particularly those featuring dark timber, stone accents, or modern minimalist design.
This heater includes Wi-Fi connectivity for smartphone control, plus an external wall-mounted controller with a digital LCD display. Control your sauna from anywhere using the free app, or adjust settings at the controller outside your sauna door.
The Wi-Fi system includes a compact wireless adapter that connects to your home network. Setup takes just minutes, and the app works with both iOS and Android devices.
Choose from four power options to match your sauna room size. All of our sauna heaters are TÜV Safety Certified.
Delivery
Free delivery throughout Thailand. Standard delivery timeframe is 3–6 weeks from order confirmation.
Heater, controller, Wi-Fi adapter, and stones ship separately (2 boxes total). Delivery to the ground floor or building loading dock. Stairs or lift access may incur additional handling fees.
Installation
Professional electrical installation required. The heater must be hardwired to a dedicated circuit by a licensed electrician.
The Prism heater can be floor-mounted or wall-mounted, depending on your sauna layout. The compact footprint and tall profile suit corner installations. Maintain a minimum 40cm clearance between the top of the heater and the ceiling.
The external controller requires a small hole through the sauna wall for the cable connection. Your electrician or installer can drill this during setup.
RonYen Sauna provides installation guidance but does not install standalone heaters. We recommend hiring a local electrician familiar with high-amperage appliance installation.
Wi-Fi setup is simple. The adapter plugs into the controller, connects to your home Wi-Fi network, and pairs with the app in minutes. No technical expertise required.
Installation typically requires:
Dedicated electrical circuit (30–40A depending on heater size)
Appropriate MCB/circuit breaker
Heat-resistant wiring rated for sauna conditions
Small wall penetration for controller cable
Wi-Fi network with 2.4GHz support
Adequate ceiling clearance (minimum 40cm above heater)
If an electrical item stops working within the warranty period, we’ll send you a replacement free of charge.
Stock items can be returned within 7 days of delivery in resalable condition. Custom and made to order items cannot be returned once production has begun. Faulty goods are repaired, replaced or refunded at our cost.
Outdoor and indoor cabins, barrels, cylinders, cube and modern designs, plus sauna-and-shower combos — from a compact one-person unit up to fourteen-person commercial rooms. Every model is made to order and customisable to your space. Browse saunas.
Red Cedar and Finnish Thermo Pine both handle heat and humidity beautifully — cedar for its aroma and natural rot resistance, thermo pine for its stability in wet conditions. Japanese Hinoki is our premium pick. Canadian Hemlock is excellent value for indoor cabins. We’ll match the timber to your budget, look and location.
Outdoor saunas are fully weather-sealed for gardens, rooftops and pool decks. Indoor models are built for bathrooms, gyms and spare rooms. Both use the same indoor-rated electric stone heaters — the difference is the exterior cladding and weatherproofing.
It depends on the internal volume of the cabin. As a guide: 4.5kW for 3–6 m³, 6kW for 5–8 m³, 9kW for 8–11 m³, 12kW for 11–15 m³, 15kW for 13–18 m³ and 18kW for 15–20 m³. Above 20 m³ takes two heaters. Up to and including 9kW runs on single phase; above that is three phase only, which in practice means anything from a six-person cabin upwards. We confirm the exact requirement in your quote so your electrician knows precisely what to install.
Both are food-grade and corrosion-resistant. 316 adds extra protection for coastal air and chlorinated water, so it’s the safer choice near the sea or beside a pool. 304 is excellent value everywhere else. We’ll recommend the right grade for your site. See ice baths.
Ice works to get started, but it melts fast in Thailand and gets expensive. A chiller holds a precise temperature day after day with no effort — it’s the easiest way to make cold therapy a daily habit rather than an occasional event.
Our chillers run from 0°C to 42°C, so the same unit chills in the hot season and heats in the cool one. Most people plunge between 3°C and 10°C. Beginners usually start around 12–15°C and work down over a few weeks.
Our chillers include filtration and ozone sanitation that keep the water fresh for weeks between changes. We walk you through simple water care at handover — it’s far less work than a pool.
Yes. Our brochures are on the site as downloads and we can email them to you. Because every sauna is made to order, the catalogue shows configurations and starting prices rather than a fixed range. Download the brochures.
The room dimensions, whether it is indoor or outdoor, how many people, and roughly where you are. If you have a floor plan, send that. From those four things we can quote accurately.
Yes, three ways. Come to the wellness garden and showroom in Ban Suan, Chonburi, ten minutes from Central Chonburi — there is a working sauna and ice baths you can use, by appointment. We hold finished samples of all four timbers. Or we will bring the samples to you: we travel anywhere in Thailand for a fee, and that fee comes off the price of your order when you buy. Book a consultation.
Yes. RonYen Wellness Co., Ltd is VAT registered and can issue full tax invoices. Ask us for the registration document if your accounts department needs it for approval.
Yes. We deliver to Koh Samui, Koh Phangan, Koh Tao, Koh Kood and Phuket regularly. Island delivery carries a supplement over mainland freight, quoted per job, and adds a few days. Tell us the island and we will price it with the quote rather than after.
We service Thailand and Laos. We are not set up for shipping further afield at the moment.
Mainland delivery is included in the price. Islands and remote provinces carry a supplement, quoted with your order.
Yes — we deliver right across Thailand by freight. Wherever you are, we’ll get it to you. Delivery details.
Occasionally, depending on the unit and where it is. Send us photographs of the heater, the control gear and the cabin and we will tell you honestly whether it is worth us coming or whether a local electrician can sort it for less.
Heater elements, stones, control panels and thermostats for the heaters we supply, held in Thailand. If you have another brand, tell us the model and we will say whether we can help.
Not currently.
Yes, for saunas in commercial operation. A room running twelve hours a day carries four to six times the load of a home installation, and scheduled servicing is what keeps it performing and keeps the warranty intact. Commercial servicing.
Yes — every sauna arrives in a sealed timber crate with the wall sections already built, and most assemble in a day with two or three people and the supplied instructions. No specialist tools needed. Prefer it done for you? Our team can handle the full install. Installation service.
Delivery to the spot, full assembly, levelling, fitting the heater, and a handover walkthrough so it’s ready to use the same day. It’s the easy option if you’d rather not build it yourself.
A firm, level base — a concrete pad, deck or paved area — plus a power point within reach for the heater. We send a simple prep checklist before delivery so everything’s ready when your sauna arrives.
The final hard-wire connection of the heater should be made by a licensed electrician — that part isn’t included, for safety and compliance. We supply the full heater specification and can recommend trusted local contractors.
Reserve online in a couple of minutes — pick a plan, a date and a time slot, and choose to pay online or on arrival. You’ll get a confirmation by email and text.
The Garden runs on advance bookings so every session has the space to itself — so book ahead if you can. That said, if you're passing and spot us, scan the sign at the gate or give us a call, and if there's room in the current session we'll happily wave you in.
Saunas, ice baths, a swimming pool and shaded lounge areas — everything you need for the full hot-and-cold circuit, in a quiet private garden. A towel, flip-flops, a locker and your first drink come free with every visit. Explore the garden.
It’s in Chonburi, easily reached from Bangkok and Pattaya. We’re in a private gated community — when you arrive, look for the RonYen sign at the gate and we’ll open it for you. We text a reminder before your session so we’re ready and waiting.
Get a straight answer on what suits your space, budget and the Thai climate — free and with no pressure.
Book a free consultation
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A sauna or ice bath is a long-term addition to your home or commercial space. Tell us about your project, your goals and your timeline — we’ll give you a straight answer, including what the right options are.
Free consultation. Phone call, video call, or visit our showroom in Ban Suan, Chonburi — Rön Yen Shop & Wellness Garden — by appointment. Tell us your space and budget, and we’ll talk through the options with no pressure to buy.
Ban Suan, Chonburi — 10 minutes from Central Chonburi
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