🚿 Harvia HGX90XW 9kW WiFi Steam Generator – 3-17 m³ Capacity

Professional-grade 9kW performance with WiFi control for larger home steam rooms and boutique spa installations

📋 Product Overview

The Harvia HGX90XW steps up to serious steam room performance, delivering 9kW of power and an impressive 12 kg/h steam output for rooms up to 17 m³. This is where home wellness meets commercial capability—powerful enough for larger dedicated steam rooms, family-sized installations, and boutique spa environments, yet still compact and smart enough for residential use.

Engineered by Harvia, the Finnish company that has led the global sauna and spa industry for over 70 years, the HGX90XW combines robust three-phase power delivery with sophisticated WiFi connectivity. The MyHarvia smartphone app puts remote control in your pocket, while the elegant Xenio WiFi touchscreen manages every aspect of your steam experience—temperature, timing, lighting, ventilation, and aromatherapy.

Despite its increased power, the HGX90XW maintains the same compact 230 × 150 × 530 mm wall-mounted profile as smaller models, making installation straightforward even in tight service areas. The 4.0-litre steel water container and integrated sediment collection system ensure dependable, low-maintenance operation through years of regular use. For homeowners who want genuinely impressive steam room performance, or wellness businesses seeking reliable equipment for client facilities, the HGX90XW delivers the capacity and quality that serious steam enthusiasts demand.

💫 Key Features

✅ 9kW Power Output – Generates a substantial 12 kg/h of soft, enveloping steam for rooms up to 17 m³

✅ MyHarvia WiFi App – Start sessions remotely, monitor real-time temperature, and control your steam room from anywhere

✅ Xenio WiFi Touchscreen – Comprehensive control panel manages steam, fragrance, lighting, and ventilation seamlessly

✅ Three-Phase Power – 400V 3N~ supply delivers stable, efficient power for demanding performance

✅ Compact Despite Power – Same slim 230 × 150 × 530 mm dimensions as smaller models

✅ 4.0 Litre Steel Reservoir – Robust water container with integrated sediment cup protects heating elements

✅ 30-55°C Temperature Control – Precisely adjustable to your preferred steam room environment

✅ Extended Timer Options – Sessions from 10 minutes to 24 hours with delay start up to 12 hours

✅ Manual Discharge Valve – Standard fitting for easy maintenance; optional auto-drain available

✅ Aromatherapy Compatible – Connect optional Harvia fragrance pump for essential oil infusion

✅ CE and EAC Certified – Full European safety approvals with IPX2 splash protection

✅ 2-Year Domestic Warranty – Comprehensive Harvia manufacturer coverage for residential installations

🔩 Technical Specifications

Specification	Value
Model	HGX90XW
GTIN	6417659031530
Power Output	9 kW
Steam Output	12 kg/h
Room Capacity	3–17 m³ (varies by wall type)
Voltage	400V 3N~ (three-phase only)
Fuses (400V 3N~)	3 × 16 A
Supply Cable	5 × 2.5 mm²
Light Lead	1.5 mm²
Dimensions (H × W × D)	230 × 150 × 530 mm
Net Weight	9.7 kg
Water Container Volume	4.0 litres
Temperature Range	30–55 °C
Timer Range	10 minutes – 24 hours
Delay Start	10 minutes – 12 hours
Water Pressure Required	1.5 – 4.0 bar
Water Inlet Connection	G¾” male
Water Outlet/Drain	G½” female
Steam Outlet Connection	Ø18 mm
Control Unit Cable Length	5.0 m
Sensor Cable Length	5.0 m
Max Light Connection	100 W
Max Fan Connection	100 W
Main Material	Steel
IP Rating	IPX2
Installation	Wall mounted
Certifications	CE, EAC
Warranty (Domestic)	2 years
Warranty (Commercial)	1 year

🏠 Room Sizing Guide

The HGX90XW covers steam rooms from 3 to 17 m³, bridging the gap between residential and light commercial applications. Your actual capacity depends on wall construction and ventilation configuration.

Room Volume by Wall Type

Wall Construction	Not Ventilated	Ventilated
Light wall (acrylic, glass, etc.)	9.0–17.0 m³	6.0–12.0 m³
Tiled light wall	7.5–14.0 m³	4.5–10.0 m³
Tiled stone wall	6.0–11.5 m³	3.0–8.0 m³

Understanding Capacity Factors

• Light walls (acrylic, glass, composite panels) retain heat efficiently, allowing maximum room coverage
• Tiled light walls (ceramic or porcelain on standard substrates) absorb moderate heat during warm-up
• Tiled stone walls (marble, granite, slate, natural stone) absorb significant thermal energy—expect reduced capacity
• Ventilated rooms continuously lose heat, requiring more steam output per cubic metre

Sizing Worked Examples

📍 Example 1: Family steam room 2.5m × 2.5m × 2.4m with ceramic tiles

• Base volume: 2.5 × 2.5 × 2.4 = 15 m³
• Wall type: Tiled light wall, not ventilated
• HGX90XW capacity: 7.5–14.0 m³
• Result: ⚠️ At upper limit – suitable but consider HGX110XW for faster recovery

📍 Example 2: Luxury home spa 3.0m × 2.0m × 2.3m with glass walls

• Base volume: 3.0 × 2.0 × 2.3 = 13.8 m³
• Wall type: Light wall (glass), not ventilated
• HGX90XW capacity: 9.0–17.0 m³
• Result: ✅ Excellent match – comfortably within optimal range

📍 Example 3: Boutique spa treatment room 2.5m × 2.0m × 2.2m with marble finishes

• Base volume: 2.5 × 2.0 × 2.2 = 11 m³
• Wall type: Tiled stone wall, not ventilated
• HGX90XW capacity: 6.0–11.5 m³
• Result: ✅ Good fit – within range for stone walls

📍 Example 4: Gym steam room 3.0m × 2.5m × 2.4m with tiles and extractor

• Base volume: 3.0 × 2.5 × 2.4 = 18 m³
• Wall type: Tiled light wall, ventilated
• HGX90XW capacity: 4.5–10.0 m³
• Result: ❌ Too large – requires HGX110XW or HGX150XW

💡 Tip: The HGX90XW excels in larger residential and smaller commercial settings. For rooms with heavy stone finishes or continuous ventilation, consider sizing up to ensure quick heat-up and stable temperatures during use.

📊 Running Costs

Energy Rate Used: £0.245/kWh (UK average – verify current rates at ofgem.gov.uk)

Estimated Running Costs

Usage Pattern	Sessions/Week	Annual Hours	Annual Cost	Cost Per Session
🏠 Light Use	2	~50	£110	£2.21
🏠 Regular Use	4	~100	£221	£2.21
🧖 Heavy Use	6	~150	£331	£2.21

Cost Calculation

Per 30-minute session at full power:
9 kW × 0.5 hours × £0.245 = £1.10

Per 60-minute session at full power:
9 kW × 1.0 hours × £0.245 = £2.21

⚠️ Actual consumption varies based on room size, insulation quality, ambient temperature, and energy tariff. The generator cycles to maintain set temperature, so real-world usage typically runs 60-80% of rated power once the room reaches temperature.

Value Perspective

At approximately £1.10–£2.21 per session, the HGX90XW delivers spa-quality steam experiences at a fraction of commercial spa visit costs. For families or couples sharing sessions, the per-person cost becomes remarkably economical.

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⚠️ Installation Requirements

Electrical Requirements

Requirement	Specification
Voltage	400V 3N~ (three-phase only)
Fuse Rating	3 × 16 A
Supply Cable	5 × 2.5 mm²
Dedicated Circuit	Required
RCD Protection	Required

Important: The HGX90XW requires a three-phase 400V electrical supply. This is standard in many UK properties, particularly newer builds and properties with electric vehicle charging or workshop facilities. If your property only has single-phase supply, consult a qualified electrician about upgrade options, or consider the HGX60XW which offers dual voltage flexibility.

Location Requirements

Requirement	Specification
Mounting	Wall mounted (horizontal)
Maximum steam pipe length	10 metres (properly insulated)
Steam pipe specification	15 mm internal diameter copper
Temperature sensor position	Ceiling or wall, 1700–3000 mm above floor
Sensor cable length	5.0 m (supplied)
Control panel cable length	5.0 m (supplied)
Ventilation	Adequate airflow around unit required
Access	Front panel removable for servicing

⚠️ IMPORTANT: Installation must be carried out by a qualified electrician 
and plumber in accordance with BS 7671 (IET Wiring Regulations), 
Water Supply Regulations, and local building codes. Three-phase supply 
with dedicated circuit and RCD protection is mandatory.

🔧 Water Requirements

Water Supply

Requirement	Specification
Water pressure	1.5 – 4.0 bar
Connection	G¾” male
Water type	Cold mains supply
Water quality	Soft water recommended

Drainage

Requirement	Specification
Drain connection	G½” female
Drain type	Gravity drain to floor waste
Manual discharge valve	Included as standard
Automatic drain valve	Optional accessory

Water Hardness Guidance

Water Hardness	Recommendation
Soft (below 100 ppm)	Standard operation
Moderately hard (100–200 ppm)	Monitor descaling frequency
Hard (200–300 ppm)	Water softener recommended
Very hard (above 300 ppm)	Water softener essential

With 9kW of power driving higher steam production, water quality becomes increasingly important. Hard water accelerates scale buildup on heating elements, reducing efficiency and lifespan. The integrated sediment cup captures deposits, and a service indicator illuminates after 200 hours of operation.

🔒 Safety Features & Certifications

Built-in Safety Systems

• ✅ Overheat Protection – Automatic cut-off with manual reset prevents thermal damage
• ✅ Low Water Level Cut-off – Sensor prevents dry running and protects heating elements
• ✅ Pressure Relief Valve – Safety valve prevents dangerous over-pressurisation
• ✅ Maximum Timer Limit – Configurable up to 24 hours with automatic shut-off
• ✅ Power Failure Memory – Selectable restart behaviour (ON1/ON2/OFF modes) after power interruptions
• ✅ Separate Water Measurement – Clean water measuring cup ensures accurate level readings unaffected by sediment

Certifications

Certification	Description
CE	European Conformity
EAC	Eurasian Conformity
IPX2	Protected against dripping water when tilted up to 15°

📍 Ideal Applications

The HGX90XW 9kW bridges residential and light commercial requirements:

Application	Typical Size	Capacity	Suitability
🏠 Large Family Steam Room	8–14 m³	3–4 people	⭐ Excellent
🧖 Private Home Spa	9–15 m³	2–4 people	⭐ Excellent
💆 Boutique Spa Treatment Room	8–12 m³	2–3 people	⭐ Excellent
🏋️ Small Gym Steam Room	6–10 m³	3–5 people	✅ Good
🏨 B&B/Small Hotel Spa	8–14 m³	2–4 people	✅ Good
♨️ Residential Hammam	7–12 m³	2–3 people	✅ Good

Perfect For

• Homeowners building larger dedicated steam rooms (10+ m³)
• Family steam rooms designed for multiple simultaneous users
• Self-build wellness suites with generous proportions
• Boutique spa businesses with treatment room requirements
• B&B or holiday let operators adding wellness amenities
• Home gym installations with integrated steam facilities

Consider the HGX90XW Over Smaller Models If

• Your room exceeds 8 m³
• Multiple users will steam simultaneously
• You have stone or heavy tile finishes
• Fast warm-up time is a priority
• You want headroom for consistent performance

Consider the Next Size Up (HGX110XW or HGX150XW) If

• Your room exceeds 14 m³ with standard tiles
• Heavy commercial usage is anticipated
• The room has continuous mechanical ventilation
• Natural stone covers extensive wall areas

📱 Control Options & Accessories

Included with HGX90XW

• ✅ Harvia HGX90XW steam generator unit
• ✅ Xenio WiFi touchscreen control panel
• ✅ Temperature sensor with 5.0 m cable
• ✅ Steam nozzle (1 piece)
• ✅ Manual discharge valve
• ✅ Sediment collection cup

Xenio WiFi Control Panel Features

Function	Capability
Temperature control	30–55 °C adjustable
Session timer	10 min – 24 hours
Delay start	10 min – 12 hours
Fragrance pump	Adjustable intensity (with optional pump)
Lighting control	Up to 100 W
Fan/ventilation	Up to 100 W with dehumidify mode
WiFi connectivity	MyHarvia app for iOS and Android
Multidrive	Control up to 4 linked generators

Multidrive Capability

For very large installations, up to four Harvia HGX or HGP steam generators can be linked together and controlled from a single Xenio panel. This makes the HGX90XW a building block for commercial-scale projects requiring 18kW, 27kW, or even 36kW of combined steam output.

Compatible Accessories

Accessory	Model Code	Description
Fragrance Pump (Large)	HWF01XL	Essential oil injection system
Fragrance Pump (Medium)	HWF01M	Compact aroma delivery
Automatic Drain Valve	Optional	Automated post-session flushing
Steam Nozzle	ZG-500	Additional/replacement outlet

✨ Aromatherapy

Elevate your steam sessions with optional fragrance injection:

Feature	Specification
Aromatherapy compatible	Yes (optional pump required)
Control	Via Xenio panel – adjustable intensity
Compatible pumps	HWF01XL (large), HWF01M (medium)
Recommended oils	Water-soluble essential oils for steam

Popular Aromatherapy Choices:

• Eucalyptus – Respiratory clarity and invigoration
• Lavender – Deep relaxation and stress relief
• Menthol/Mint – Cooling sensation and mental alertness
• Pine/Cedar – Authentic Nordic forest atmosphere
• Citrus blends – Energising morning sessions

ℹ️ Frequently Asked Questions

Q: What size steam room suits the HGX90XW? A: The HGX90XW covers rooms from 3 to 17 m³, depending on wall materials and ventilation. With glass or acrylic walls and no ventilation, capacity reaches 17 m³. With tiled stone walls, maximum reduces to around 11.5 m³. Consult the sizing tables for your specific configuration.

Q: Does this model require three-phase power? A: Yes, the HGX90XW operates exclusively on 400V three-phase supply with 3 × 16A fuses. Many UK properties have three-phase available, but if yours doesn’t, consult an electrician about upgrade options or consider the dual-voltage HGX60XW.

Q: How does it compare to the HGX60XW? A: The HGX90XW produces 12 kg/h steam versus 7.6 kg/h from the HGX60XW—approximately 58% more output. This means significantly faster warm-up, better temperature recovery, and suitability for rooms up to 17 m³ versus 11 m³.

Q: Can I control it from my phone? A: Yes, all HGX WiFi models include MyHarvia app connectivity. Start sessions remotely, monitor temperature, set timers, and receive notifications—all from your smartphone.

Q: Is this suitable for commercial use? A: Yes, the HGX90XW is designed for both residential and light commercial applications. Harvia provides a 1-year warranty for commercial installations (versus 2 years domestic). For heavier commercial use or larger rooms, consider the HGX110XW or HGX150XW.

Q: How long does it take to heat up? A: Warm-up time depends on room size and insulation. A typical 10-12 m³ well-insulated room reaches bathing temperature in approximately 15-25 minutes. The delay start feature lets you schedule sessions in advance.

Q: Is a water softener necessary? A: In hard water areas (above 200 ppm), a water softener is strongly recommended—especially important at this power level where scale buildup impacts performance more significantly. The sediment cup helps, but prevention is more effective than cure.

Q: What’s included in the delivery? A: The HGX90XW includes the generator unit, Xenio WiFi control panel, temperature sensor (5m cable), steam nozzle, manual discharge valve, and sediment cup. Copper steam pipe (15mm ID) must be sourced separately.

Q: Can multiple generators be linked together? A: Yes, up to four Harvia HGX or HGP generators can be connected via the multidrive feature and controlled from a single Xenio panel—ideal for large commercial installations.

Q: What warranty coverage applies? A: Harvia provides a 2-year warranty for domestic use and 1-year for commercial installations. Valid warranty requires proper installation and adherence to maintenance schedules per the manual.

📑 Downloads & Resources

 Installation & User Manual – Wiring diagrams, setup, and operation Available from harvia.com

🏆 Why Choose the Harvia HGX90XW

• ✅ Serious Steam Power – 9kW output delivers 12 kg/h for rooms up to 17 m³
• ✅ Finnish Engineering Excellence – 70+ years of Harvia innovation and expertise
• ✅ Smart Connected Control – WiFi and app integration for modern convenience
• ✅ Scalable Architecture – Multidrive links up to 4 units for large projects
• ✅ Compact Despite Power – Same slim footprint as smaller models
• ✅ Dual-Purpose Design – Suits both residential and light commercial use
• ✅ Reliable Construction – Steel housing engineered for demanding operation
• ✅ Comprehensive Safety – Full protection systems with CE/EAC certification
• ✅ Simplified Maintenance – Sediment cup and accessible panels ease servicing
• ✅ Warranty Backed – 2-year domestic / 1-year commercial coverage

⭐ Why Buy from Parts4Tubs

• ✅ UK-based company with knowledgeable local support
• ✅ Fast UK delivery on in-stock items
• ✅ Expert advice from steam room and spa specialists
• ✅ Competitive pricing on genuine Harvia products
• ✅ Full manufacturer warranty support
• ✅ Hassle-free returns within 30 days
• ✅ Technical guidance for sizing and installation queries

🌫️ Summary

The Harvia HGX90XW 9kW WiFi Steam Generator delivers serious performance for larger home steam rooms and light commercial installations, producing 12 kg/h of luxurious steam for spaces from 3–17 m³. Three-phase power ensures stable, efficient operation, while MyHarvia app connectivity and Xenio touchscreen controls bring sophisticated smart control to your wellness routine. With multidrive capability for linking multiple units, CE/EAC certification, and Harvia’s 70+ years of Finnish expertise, the HGX90XW provides the foundation for exceptional steam experiences. Running costs from approximately £1.10 per 30-minute session make regular use genuinely affordable. Order from Parts4Tubs for fast UK delivery and expert support.