♨️ LX H30-RS1 3.0kW Spa Heater with Thermoregulator – Compact Flow-Through Heating for Hot Tubs & Bespoke Projects

Compact, self-regulating heating with built-in temperature control and safety protection

💧 Product Overview

The LX H30-RS1 is a compact 3.0kW flow-through heater assembly with a built-in thermoregulator, manufactured by LX (also known as LX Whirlpool), a trusted name in spa and hot tub components. This self-contained heating unit is designed for hot tubs, whirlpool baths, small pools and bespoke heating projects — delivering reliable, thermostatically controlled water heating in a remarkably small package.

Unlike standard spa heaters that rely on an external control system for temperature regulation, the H30-RS1 features an integrated adjustable thermostat dial on the side of the unit, allowing you to set and maintain your desired water temperature independently. Combined with a built-in paddle-operated flow switch and high-limit thermal cutout, this heater provides a complete, standalone heating solution. The Incoloy 825 heating element ensures excellent corrosion resistance in chemically treated spa water, whilst the compact design allows installation in tight spaces where larger heater assemblies simply cannot fit.

Whether you are replacing an existing heater in a Chinese-manufactured spa, upgrading from the older 2.0kW H20-RS1 model, or building a bespoke hot tub project from scratch, the LX H30-RS1 offers the perfect combination of power, safety and simplicity.

✨ Key Features

• ✅ 3.0kW Heating Power – Rapid, efficient water heating for hot tubs, spas and small pools
• ✅ Built-In Thermoregulator – Adjustable temperature dial (0–45°C) on the side of the unit for independent temperature control
• ✅ Incoloy 825 Heating Element – High-alloy steel specifically designed for aggressive, chemically treated water environments
• ✅ Integrated Flow Switch – Paddle-operated flow detection ensures the heater only operates when adequate water flow is present
• ✅ High-Limit Thermal Cutout – Built-in overheat protection (60°C) with reset button prevents dangerous overheating
• ✅ Compact Design – Small footprint allows installation in confined spaces
• ✅ 1.5″ Plumbing Connections – White plastic female unions included for straightforward plumbing integration
• ✅ IPX5 Water Resistance – Rated for protection against water jets from any direction
• ✅ CE Approved – Meets European safety and quality standards
• ✅ Power Cord Connection – Simple electrical connection via included power cord
• ✅ Replacement for H20-RS1 – Direct upgrade from the 2.0kW version with faster heating and no increase in total energy consumption

🔧 Technical Specifications

Specification	Value
Heater Type	Flow-through with integrated thermoregulator
Heating Power	3.0 kW
Supply Voltage	220–240V AC
Frequency	50/60 Hz
Current Draw	13.4–13.6 A
Thermostat Range	0–45°C (adjustable dial)
Thermostat Accuracy	±2°C
High-Limit Cutout	60°C (with reset button)
Maximum Working Pressure	1 Bar
Minimum Operating Flow	3.6 m³/hr (60 litres per minute)
Minimum Recommended Pump	0.25 HP / 170W (350W+ recommended)
Heating Element Material	Incoloy 825
Housing Material	Plastic
Plumbing Connection	1.5″ (48–48.5 mm)
Connection Type	White plastic female unions (included)
Flow Detection	Paddle-operated pressure switch
Temperature Sensor	Integrated probe (built-in)
Power Connection	Cord (1.2 m cable)
IP Rating	IPX5
Certifications	CE
Manufacturer Part Number (MPN)	H30-RS1
Parts4Tubs Part Code	HT-LX311

📐 Dimensions

Measurement	Value
Body Length (without unions)	130–170 mm
Total Length (with unions)	205–340 mm
Height	120–150 mm
Heater Tube Diameter	50 mm
Package Weight	1.7 kg
Package Size	230 × 190 × 180 mm

⚠️ Note: Dimension variations reflect different measurement methods across suppliers. The union pipes insert approximately 30 mm into the unions. Please measure your available installation space carefully before purchase. Contact Parts4Tubs for exact dimensions if required.

⚡ Electrical Requirements

Electrical Specification	Requirement
Supply Voltage	220–240V AC
Frequency	50/60 Hz
Phase	Single
Current Draw	13.4–13.6 A
Power	3.0 kW
Connection	Power cord (1.2 m)
Minimum Circuit Breaker	16 A (recommended)
Cable Size (Recommended)	2.5 mm²

⚠️ IMPORTANT ELECTRICAL SAFETY:

• All electrical work must be carried out by a qualified electrician in accordance with UK wiring regulations (BS 7671).
• Hot tubs and spa installations require RCD protection (30 mA).
• Ensure the supply circuit can safely handle the 13.4–13.6 A current draw.
• The heater must be wired in conjunction with your circulation pump so the heater only operates when the pump is running.
• Never operate the heater without water flow — this will cause damage to the heating element and void any warranty.

🔄 How the H30-RS1 Flow-Through Heater Works

The LX H30-RS1 operates on a simple but effective principle:

1. Water Circulation – Your spa’s circulation pump draws water through the plumbing system and pushes it through the heater assembly.
2. Flow Detection – The built-in paddle-operated flow switch detects adequate water flow before allowing the heating element to activate.
3. Heating – Water passes over the 3.0 kW Incoloy 825 heating element, which rapidly raises the water temperature as it flows through.
4. Temperature Regulation – The integrated thermoregulator dial on the side of the unit monitors water temperature and cycles the heater on and off to maintain your set temperature (0–45°C, accurate to ±2°C).
5. Safety Protection – If water temperature exceeds 60°C for any reason, the high-limit thermal cutout automatically shuts down the heater. A reset button on the unit allows you to restart after the cause has been investigated and resolved.

🛠️ Installation Requirements

Mounting & Positioning

Requirement	Specification
Mounting Position	Horizontal ONLY
Location	In-line on the pump’s suction (inlet) pipe
Base	Secure, stable mounting
Clearance	Adequate access for thermostat adjustment and maintenance

Plumbing

Connection	Specification
Inlet	1.5″ (48–48.5 mm) female union (included)
Outlet	1.5″ (48–48.5 mm) female union (included)
Union Type	White plastic female sockets
Included	Unions and O-ring gaskets

Installation Notes

⚠️ The heater MUST be fitted in a horizontal position — vertical mounting is not supported and may cause malfunction.

⚠️ Adequate water flow is essential. The built-in pressure switch requires sufficient back pressure to activate. If the heater is plumbed straight to a large bore outlet with no bends in the pipe run, there may be insufficient back pressure and the flow switch may not trigger. Ensure your plumbing configuration includes enough resistance (bends, reducers, or a longer pipe run) to create the necessary pressure.

⚠️ Minimum pump requirement: A circulation pump of at least 0.25 HP / 170W is required. LX Whirlpool recommends a minimum 350W circulation pump, especially if the plant room is not immediately adjacent to the spa.

⚠️ Never run the heater dry — this will damage the heating element and void the warranty.

⚠️ Wire the heater in conjunction with the pump — the heater should only receive power when the pump is running to ensure water flow through the heating element at all times.

💡 Installation Tip: Plumb the heater on the suction (inlet) side of the circulation pump and wire it in conjunction with your pump’s electrical supply. When the pump runs, the heater will activate automatically if the thermostat calls for heat.

🔗 Compatibility Guide

Compatible Applications

The LX H30-RS1 is a versatile standalone heater suitable for:

• Most Chinese-manufactured hot tubs and spas (may require minor plumbing adjustment)
• Bespoke / self-build hot tub projects
• Whirlpool baths
• Small pools
• Ponds (heated)
• Any 1.5″ plumbing system requiring thermostatically controlled water heating

Direct Replacement / Upgrade For

Model	Relationship
LX H20-RS1 (2.0 kW)	Direct upgrade — the H30-RS1 heats faster without consuming more total energy
Older Rooster heaters	Common replacement — more reliable and durable

Works With

Component	Compatibility
Spa control packs	Can operate independently (standalone) or integrate with existing spa packs
Circulation pumps	Any pump providing minimum 0.25 HP / 170W (350W+ recommended)
Plumbing	Standard 1.5″ (48 mm) spa plumbing

🔧 Maintenance Guide

Routine Maintenance

Task	Frequency	Notes
Check for leaks	Monthly	Inspect around unions and O-ring gaskets
Inspect unions	Monthly	Tighten if any sign of weeping
Check O-ring gaskets	Every 6 months	Replace if worn, cracked or compressed
Test thermostat accuracy	Annually	Compare dial setting against measured water temperature
Inspect power cord	Quarterly	Check for damage, fraying or signs of heat
Clean heater tube	As needed	Remove scale buildup if water flow is reduced
Test high-limit cutout	Annually	Ensure the safety trip functions correctly

Warning Signs – Replace Heater If:

• Water leaking from the heater body (not union connections)
• Heater fails to reach set temperature despite adequate flow
• High-limit cutout trips repeatedly without apparent cause
• Visible damage or corrosion to the heating element
• Unusual buzzing, clicking or arcing sounds
• Circuit breaker trips when heater activates
• Thermostat dial no longer adjusts temperature

🎯 Ideal Applications

Application	Suitability	Notes
♨️ Hot tub / spa heating	✅ Excellent	Primary designed application — standalone or integrated
🛁 Whirlpool bath	✅ Excellent	Compact size ideal for bath installations
♨️ Bespoke / self-build hot tub	✅ Excellent	Standalone thermoregulator makes it perfect for DIY projects
🏊 Small pool heating	✅ Good	Suitable for basic pool heating with adequate circulation
♨️ Chinese spa replacement	✅ Excellent	Common replacement — may require minor plumbing change
💧 Pond heating	✅ Good	Suitable with appropriate circulation pump
♨️ Upgrade from H20-RS1 (2 kW)	✅ Direct upgrade	Heats faster, same total energy consumption

❓ Frequently Asked Questions

Q: What is the heating power of the LX H30-RS1? A: The LX H30-RS1 delivers 3.0 kW of heating power, operating at 220–240V AC and drawing 13.4–13.6 A.

Q: How does the thermoregulator work? A: The heater features a built-in adjustable thermostat dial on the side of the unit. Simply turn the dial to set your desired water temperature between 0°C and 45°C. The integrated temperature probe monitors the water and cycles the heater on and off to maintain your set temperature within ±2°C accuracy.

Q: Can I use this heater without a spa control pack? A: Yes. The H30-RS1 is a standalone heater with its own built-in thermoregulator, flow switch and safety cutout. It does not require a separate spa control system to function — simply wire it in conjunction with a circulation pump and it operates independently.

Q: What size plumbing connections does this heater use? A: The H30-RS1 uses 1.5″ (48–48.5 mm) plumbing connections. White plastic female unions and O-ring gaskets are included with the heater.

Q: Does the heater have to be fitted horizontally? A: Yes. The LX H30-RS1 must be installed in a horizontal position. Vertical installation is not supported and may cause the flow switch or thermostat to malfunction.

Q: What minimum pump size do I need? A: A minimum of 0.25 HP / 170W is required to ensure adequate water flow. However, LX Whirlpool recommends a 350W or larger circulation pump, particularly if the heater is installed some distance from the spa or pool.

Q: Is this an upgrade from the H20-RS1? A: Yes. The H30-RS1 is a direct replacement and upgrade for the older 2.0 kW H20-RS1 model. It heats water faster thanks to the higher 3.0 kW output, but does not consume more total energy — the heating cycle is simply more intense but shorter in duration.

Q: What safety features does this heater have? A: The H30-RS1 includes three layers of safety protection: (1) a paddle-operated flow switch that prevents heating without adequate water flow, (2) an adjustable thermostat that maintains your set temperature, and (3) a high-limit thermal cutout at 60°C with a manual reset button that shuts down the heater if it overheats.

Q: What voltage does this heater require? A: 220–240V AC at 50/60 Hz. All electrical installation must be carried out by a qualified electrician in accordance with UK wiring regulations (BS 7671). RCD protection (30 mA) is required for all hot tub and spa electrical installations.

Q: Will this fit my Chinese-manufactured hot tub? A: The H30-RS1 is compatible with most Chinese-manufactured spas, though a minor plumbing adjustment may be required depending on your specific model. It is a common and popular replacement heater for this type of spa.

Q: What is the maximum water temperature this heater can reach? A: The adjustable thermostat allows you to set temperatures up to 45°C. The high-limit safety cutout is set at 60°C and will automatically shut down the heater if this temperature is exceeded for any reason.

🏆 Why Choose the LX H30-RS1

• ✅ Standalone Operation – Built-in thermoregulator means no external control system required
• ✅ Powerful 3.0 kW Heating – Rapid water heating with Incoloy 825 corrosion-resistant element
• ✅ Triple Safety Protection – Flow switch, adjustable thermostat and high-limit cutout
• ✅ Compact Design – Fits in tight spaces where larger heaters cannot
• ✅ Simple Installation – Horizontal in-line mounting with included 1.5″ unions and O-rings
• ✅ Versatile Applications – Hot tubs, whirlpool baths, small pools, bespoke projects
• ✅ Proven Reliability – Trusted LX manufacturing with CE approval and IPX5 rating
• ✅ Direct H20-RS1 Upgrade – Faster heating with no increase in total energy consumption

🤝 Why Buy from Parts4Tubs

• ✅ UK-based company with local support
• ✅ Fast UK delivery
• ✅ Expert advice from spa and hot tub specialists
• ✅ Competitive pricing
• ✅ Full warranty support
• ✅ Easy returns within 30 days
• ✅ Replacement elements, thermostats and gaskets available

✨ Summary

The LX H30-RS1 is a compact, self-contained 3.0 kW flow-through heater with built-in thermoregulator, flow switch and high-limit safety cutout. Featuring an adjustable temperature dial (0–45°C), Incoloy 825 corrosion-resistant heating element and 1.5″ plumbing connections with included unions, it is the ideal standalone heating solution for hot tubs, whirlpool baths, bespoke spa projects and Chinese spa replacements. CE approved, IPX5 rated and a direct upgrade from the 2.0 kW H20-RS1 model. Available now from Parts4Tubs at £74.06 inc. VAT.