🌊 Aquark Mr Silence MS90 Inverter Heat Pump – 9kW | Ultra-Quiet Pool & Hot Tub Heating

Experience whisper-quiet, energy-efficient heating for your swimming pool, hot tub, or swim spa. The Aquark Mr Silence MS90 combines cutting-edge inverter technology with ultra-silent operation to deliver exceptional performance while slashing your energy bills by up to 70%.

Why Choose the Aquark Mr Silence MS90?

The Mr Silence MS90 isn’t just another pool heater—it’s a revolution in quiet, efficient water heating. Whether you’re heating a compact pool, luxurious hot tub, or therapeutic swim spa, this 9kW powerhouse delivers consistent warmth without the noise, hassle, or sky-high running costs of traditional electric heaters.

🔇 Silent as a Whisper – At just 36.5 dB in Silence mode (quieter than a library), you can enjoy your pool without disturbing neighbours or your peaceful garden atmosphere.

💰 Massive Energy Savings – With inverter technology and COP ratings up to 14.0, you’ll extract 90% of your heating energy from free ambient air, cutting costs by 50-70% compared to standard electric heaters.

🌡️ All-Weather Reliability – Operates efficiently in temperatures from -7°C to 43°C, extending your swimming season from spring through autumn and beyond.

📱 Smart Control – Full WiFi connectivity with the InverGo app lets you control temperature, switch modes, and monitor performance from anywhere.

🌟 Key Features That Set This Heat Pump Apart

Ultra-Silent InverPad® Technology

The patented back-discharge airflow design redirects sound away from living areas while maximizing efficiency. At 40 dB average noise level (measured at 1 metre), this is one of the quietest pool heat pumps on the market—12 dB lower than standard on/off units.

Intelligent DC Inverter System

Unlike basic heat pumps that constantly cycle on and off, the stepless DC inverter automatically adjusts compressor speed to match heating demand. This means:

• ✅ Smoother temperature control
• ✅ Reduced wear and extended lifespan
• ✅ Optimal efficiency at partial loads
• ✅ Lower noise during normal operation

Premium Mitsubishi Compressor

Featuring a twin-rotary DC inverter compressor from Mitsubishi—a world leader in HVAC technology—this unit delivers reliable, efficient performance season after season.

Twisted Titanium Heat Exchanger

40% more efficient than standard heat exchangers and virtually immune to corrosion from chlorine, salt, and chemicals. This titanium construction ensures decades of trouble-free operation.

Eco-Friendly R32 Refrigerant

Uses next-generation R32 gas with significantly lower global warming potential (GWP) than older refrigerants, helping you reduce your carbon footprint.

WiFi & App Control

Download the free InverGo app (iOS/Android) to control your heat pump remotely. Adjust temperature, switch between Boost and Silence modes, set timers, and monitor water temperature—all from your smartphone.

Rust-Free Aluminium Cabinet

Sleek, modern ABS casing with aluminium alloy construction resists rust and weathering, maintaining its appearance in all outdoor conditions.

📊 Complete Technical Specifications

Feature	Details
Model	Aquark Mr Silence MS90
Heating Capacity (A27/W27)	9.0 kW
Heating Capacity (A15/W26)	6.5 kW
COP Range (27°C Air/27°C Water)	14.0 – 7.1
COP Range (15°C Air/26°C Water)	7.3 – 4.7
Average COP at 50% Speed	~10.4
Recommended Pool Volume	20–45 m³ (4,400–9,900 gallons)
Operating Air Temperature Range	-10°C to +43°C (14°F to 109°F)
Optimal Operating Range	15°C to 25°C
Power Supply	230V 1Ph 50Hz
Rated Input Power	0.19–1.38 kW
Rated Input Current	0.83–5.98 A
Noise Level (at 1m)	36.5 dB(A) (Silence) – 46 dB(A) (Boost)
Noise Level (at 10m)	16.8–26.1 dB(A)
Recommended Water Flow	2–4 m³/h
Water Connection	48.3 mm (1.5″ unions)
Dimensions (L × W × H)	890 × 430 × 657 mm
Weight	55 kg
Cabinet Material	Rust-free aluminium alloy with ABS casing
Compressor	Mitsubishi twin-rotary DC inverter
Heat Exchanger	Twisted titanium (40% more efficient)
Refrigerant	R32 (low GWP, eco-friendly)
Controls	Touch panel + WiFi app (InverGo)
Operating Modes	Boost Mode & Silence Mode
Defrost System	Automatic hot gas reverse cycle
Protection Features	High/low pressure, anti-freeze, water flow, temperature sensors

🎯 Who Is This Heat Pump Perfect For?

✅ Small to Medium Swimming Pools (20–45 m³ / 20,000–45,000 litres) ✅ Hot Tubs & Jacuzzis requiring quiet, efficient heating ✅ Swim Spas up to 10 metres in length ✅ Residential Properties where noise is a concern ✅ Homeowners seeking to reduce energy bills ✅ Year-Round Users wanting extended swimming seasons ✅ Eco-Conscious Buyers prioritizing sustainability

🏊 Pool Sizing & Suitability Guide

The MS90 is optimally sized for pools between 20–45 cubic metres (20,000–45,000 litres). Here’s how to work out if it’s right for your pool:

Rectangular Pool Calculator:

Volume (m³) = Length (m) × Width (m) × Average Depth (m)

Example Pool Sizes:

• 6m × 4m × 1.5m = 36 m³ ✅ Perfect fit
• 8m × 4m × 1.2m = 38.4 m³ ✅ Ideal
• 7m × 3.5m × 1.4m = 34.3 m³ ✅ Excellent match
• 5m × 3m × 1.5m = 22.5 m³ ✅ Great choice
• 10m × 5m × 1.5m = 75 m³ ⚠️ Consider larger model (MS150 or MS170)

Hot Tub & Swim Spa Suitability:

• Hot Tubs: Up to 2,000 litres (2 m³) ✅ Excellent
• Large Hot Tubs: 2,000–3,500 litres ✅ Ideal
• Swim Spas: Up to 15,000 litres (15 m³) ✅ Perfect
• Large Swim Spas: 15,000–25,000 litres ✅ Very suitable

⏱️ Heat-Up Time Estimates

How long will it take to warm your water? Use these estimates to plan your heating schedule:

Formula Used:

Time (hours) = (Pool Volume in m³ × Temperature Rise in °C × 1.16) ÷ Heat Pump kW Rating

Heat-Up Times for Various Pool Sizes:

⚠️ IMPORTANT DISCLAIMERS:

• These are estimates only based on ideal conditions
• Actual times vary with air temperature, humidity, wind, and pool insulation
• Performance decreases significantly in air temperatures below 15°C
• Using a pool cover can reduce heating time by 30-50%
• Initial heat-up from cold takes longer than daily temperature maintenance

Pool Volume	5°C Rise	10°C Rise	15°C Rise
20 m³ (20,000L)	2.6 hours	5.2 hours	7.7 hours
25 m³ (25,000L)	3.2 hours	6.4 hours	9.7 hours
30 m³ (30,000L)	3.9 hours	7.7 hours	11.6 hours
35 m³ (35,000L)	4.5 hours	9.0 hours	13.5 hours
40 m³ (40,000L)	5.2 hours	10.3 hours	15.5 hours
45 m³ (45,000L)	5.8 hours	11.6 hours	17.4 hours

Based on 9kW heating capacity at A27/W27 conditions (27°C air, 27°C water, 80% humidity)

Seasonal Performance Expectations:

Summer (Air 20–30°C):

• Near-rated performance
• COP: 10–14
• Fast heat-up times
• Most cost-effective operation

Spring/Autumn (Air 10–20°C):

• Good performance
• COP: 6–10
• Slightly longer heat-up times
• Still highly efficient

Winter (Air 0–10°C):

• Reduced but functional performance
• COP: 4–7
• Significantly longer heat-up times
• Automatic defrost cycles may activate
• Best used for maintaining temperature rather than initial heating

Below 0°C:

• Limited performance
• Primarily for temperature maintenance
• Not recommended for initial heat-up
• Ensure anti-freeze protection is active

💰 Running Cost Comparison & Energy Savings

See how much you could save compared to traditional heating methods:

Approximate Running Costs (per hour):

Based on UK electricity rate of £0.30/kWh

Heating Method	Power Draw	Cost per Hour	Annual Cost (400 hrs)
Electric Heater (9kW)	9 kW	£2.70	£1,080
Gas Heater	~25 kW gas	£1.50–£2.00	£600–£800
Mr Silence MS90 (COP 10)	0.9 kW avg	£0.27	£108
Mr Silence MS90 (COP 14)	0.64 kW avg	£0.19	£76

💡 Annual Savings Potential:

• vs Electric Heater: Save £900–£1,000 per year (90% reduction)
• vs Gas Heater: Save £500–£700 per year (70% reduction)

Payback Period: Typically 2–4 years depending on usage patterns and energy prices.

🔧 Installation Requirements & Clearances

Minimum Clearance Requirements:

• Front of unit: 200 cm (for airflow and servicing)
• Rear of unit: 50 cm minimum (back-discharge design)
• Sides: 50 cm each side
• Above: Clear space with no obstructions

Ideal Installation Location:

✅ Well-ventilated outdoor area ✅ Solid, level concrete base or mounting brackets ✅ Protected from direct rain (but not fully enclosed) ✅ Away from bedroom windows (even though it’s quiet) ✅ Close to pool equipment (within 10m of pool if possible) ✅ Access to 230V electrical supply

❌ Avoid:

• Enclosed or indoor spaces
• Areas with restricted airflow
• Directly under windows
• Areas prone to standing water
• Near combustible materials

What You’ll Need:

• Electrical: 230V 1Ph supply with RCD protection (30mA leakage current)
• Plumbing: 48.3mm (1.5″) water connections, compatible pool pump
• Base: Concrete pad or anti-vibration mounting frame
• Optional: Pool cover (highly recommended for efficiency)

Professional Installation Recommended:

While experienced DIYers can install this unit, professional installation ensures:

• Correct electrical wiring and earthing
• Proper refrigerant system integrity
• Optimal water flow rates
• Warranty compliance
• Safe operation

🎮 Operating Modes Explained

Boost Mode 🚀

• Capacity: 20–100% (variable)
• Best For: Initial heat-up from cold, rapid temperature increase
• Noise Level: 46 dB(A) at 1m
• When to Use: When you need maximum heating power
• COP Range: 7.1–14.0 (depending on conditions)

Silence Mode 🔇

• Capacity: 20–80% (variable)
• Best For: Temperature maintenance, overnight operation, noise-sensitive areas
• Noise Level: 36.5 dB(A) at 1m (3 dB quieter than Boost)
• When to Use: Once pool is at temperature, in residential areas, at night
• COP Range: Similar efficiency with quieter operation

💡 Pro Tip: Use Boost mode for initial heating, then switch to Silence mode to maintain temperature efficiently and quietly. The inverter technology ensures both modes run efficiently!

📱 WiFi Control & InverGo App Features

Take complete control of your pool heating from anywhere:

App Features:

✅ Remote Temperature Control – Adjust from 18°C to 40°C ✅ Mode Switching – Toggle between Boost and Silence ✅ Timer Programming – Set automatic on/off schedules ✅ Temperature Monitoring – View inlet water temperature in real-time ✅ Status Checking – Monitor compressor speed and system parameters ✅ Multi-User Access – Share control with family members ✅ Temperature Unit Toggle – Switch between °C and °F ✅ Weather Forecast – Plan heating around weather conditions

How to Connect:

1. Download “InverGo” app (iOS/Android)
2. Power on heat pump and unlock screen
3. Press WiFi button for 3 seconds
4. Connect via Bluetooth or WiFi from app
5. Enter your WiFi password
6. Start controlling remotely!

🛡️ Protection Features & Safety

This heat pump includes comprehensive protection systems:

✅ High Pressure Protection – Prevents compressor damage ✅ Low Pressure Protection – Safeguards refrigerant system ✅ Water Flow Protection – Detects insufficient water circulation ✅ Anti-Freeze Protection – Prevents ice damage in cold weather ✅ Temperature Sensors – Multiple probes monitor system health ✅ Automatic Defrost – Smart reverse-cycle defrosting ✅ Electrical Protection – Full protection on electrical system ✅ Time Delay Start – Prevents short-cycling damage ✅ Memory Function – Resumes settings after power interruption

🌍 Environmental Credentials

Make the eco-friendly choice:

🌱 90% Free Renewable Energy – Extracts heat from ambient air 🌱 R32 Refrigerant – 68% lower GWP than R410A 🌱 Low Carbon Operation – Significantly reduces CO₂ emissions 🌱 Energy Class A+++ – Among the most efficient pool heaters available 🌱 Extended Lifespan – Quality components reduce waste 🌱 Recyclable Materials – Aluminium and metal construction

Average Carbon Savings: Approximately 2–3 tonnes of CO₂ per year compared to electric resistance heating.

❓ Frequently Asked Questions

Q: How quiet is the Mr Silence MS90 really?

A: At 36.5 dB(A) in Silence mode, it’s quieter than a normal conversation (60 dB) and comparable to a whisper or library (30-40 dB). At 10 metres distance, it measures just 16.8–26.1 dB(A)—quieter than most modern refrigerators. Many customers report forgetting it’s even running!

Q: Can it heat my pool in winter?

A: Yes, but with reduced efficiency. The MS90 operates down to -7°C, but performance decreases significantly below 15°C air temperature. It’s ideal for extending your season in spring and autumn. For winter heating, expect longer heat-up times and higher running costs. The unit is better suited for maintaining temperature in cool weather rather than heating from cold below 10°C.

Q: What size pool is this suitable for?

A: The MS90 is optimally designed for pools between 20–45 m³ (20,000–45,000 litres). For reference, that’s roughly 6m × 4m × 1.5m deep up to 8m × 4m × 1.4m. It’s also perfect for hot tubs and swim spas up to 15–25 m³.

Q: How much will it cost to run?

A: With an average COP of 10, you’ll use approximately 0.9 kW of electricity to produce 9 kW of heat. At £0.30/kWh, that’s about £0.27 per hour—compared to £2.70 per hour for a 9kW electric heater. Typical seasonal costs range from £100–£300 depending on usage, compared to £1,000+ for electric resistance heating.

Q: Do I need a pool cover?

A: While not essential, a pool cover is highly recommended. It can reduce heat loss by 50–70%, meaning your heat pump runs less often and your bills stay lower. A cover can cut heating time by 30–50% and reduce annual running costs by hundreds of pounds. It’s one of the best investments you can make alongside your heat pump.

Q: Can I install this myself?

A: While technically possible for skilled DIYers, professional installation is strongly recommended. The unit requires proper electrical installation with RCD protection, correct water flow setup, and refrigerant system checks. Professional installation also ensures warranty compliance and optimal performance. Budget £200–£500 for professional installation.

Q: What maintenance does it need?

A: Very little! Monthly: Clean any debris from air intake. Quarterly: Check water flow and connections. Annually: Professional service to check refrigerant, electrical connections, and overall system health. In winter, drain water from the heat exchanger if temperatures will drop below freezing for extended periods.

Q: How long will it last?

A: With proper maintenance, expect 10–15 years of reliable service. The Mitsubishi compressor and titanium heat exchanger are built for longevity. Many commercial pool heat pumps using similar technology operate for 15–20 years.

Q: Does it come with a warranty?

A: Warranty terms vary by retailer. Contact your supplier for specific warranty details. Typically, expect 2–3 years parts and labour coverage from reputable UK distributors.

Q: Can it cool my pool in summer?

A: The MS90 is a heating-only model and cannot cool water. If you need cooling functionality, look for Aquark’s heating/cooling models (different series).

Q: Will it work with my existing pool pump?

A: Yes, in most cases. Your pool pump needs to provide 2–4 m³/h water flow and have a maximum lift of at least 10m. Most standard pool pumps meet this requirement. The heat pump connects in-line with your existing filtration system.

Q: What’s the difference between COP and efficiency?

A: COP (Coefficient of Performance) is the ratio of heat output to electrical input. A COP of 10 means you get 10 kW of heat for every 1 kW of electricity—that’s 1000% efficiency in traditional terms. Higher COP = lower running costs. The MS90’s COP ranges from 4.7 to 14.0 depending on conditions.

Q: How long does the defrost cycle take?

A: Automatic defrost cycles typically last 3–10 minutes and occur when outdoor temperature is between 2–7°C with high humidity. The unit will display a defrost symbol, then resume normal heating. This is completely normal and necessary for efficient operation in cooler conditions.

📥 Downloads & Documentation

📄 User Manual – Mr Silence Series 

Download Complete User Manual (PDF) (opens in new tab)

This comprehensive manual includes:

• Complete installation instructions with clearance diagrams
• Electrical wiring diagrams and specifications
• Operation guide for touch panel and WiFi app
• Technical parameter tables for all Mr Silence models
• Troubleshooting guide with error codes
• Maintenance schedule and procedures
• Safety precautions and warnings
• Warranty information and after-service details

✅ What’s Included in the Box

• 1× Aquark Mr Silence MS90 Heat Pump (9kW)
• 1× Touch Panel Controller (pre-installed)
• 1× Condensate Drainage Kit
• 1× User Manual (or download PDF above)
• Mounting hardware (check with your supplier)

Not Included (Purchase Separately):

• Water connection unions/pipes
• Electrical cable and installation materials
• Pool cover (highly recommended)
• Installation service (recommended)

🎁 Make the Smart Investment Today

The Aquark Mr Silence MS90 represents the perfect balance of performance, efficiency, and quiet operation. While the upfront cost is higher than basic heaters, the energy savings typically pay back your investment within 2–4 years—then you continue saving year after year.

Key Benefits Summary: ✅ Whisper-quiet operation (36.5 dB) won’t disturb you or neighbours ✅ Save up to 70% on heating costs vs. electric heaters ✅ WiFi control for ultimate convenience ✅ Premium Mitsubishi compressor for reliability ✅ Titanium heat exchanger for long-lasting durability ✅ Eco-friendly R32 refrigerant with low environmental impact ✅ All-weather capability extends your swimming season ✅ Perfect for pools, hot tubs, and swim spas (20–45 m³)

Investment Tip: Pair with a quality pool cover to maximize efficiency and further reduce running costs by 30–50%. The combination delivers unbeatable year-round pool heating performance.

🛒 Ready to Transform Your Pool Heating?

Get professional advice: Contact your local pool equipment specialist or Parts4Tubs to discuss installation, pricing, and any questions about suitability for your specific pool or spa.

Remember: While this heat pump dramatically reduces running costs, proper installation and use of a pool cover are essential for optimal performance and maximum savings.

Note: All performance figures, COP ratings, and heat-up time estimates are based on manufacturer specifications and ideal testing conditions (A27/W27, 80% humidity). Real-world performance varies with ambient temperature, humidity, water volume, insulation, and environmental conditions. Heat-up time estimates are provided as general guidance only and should not be considered guaranteed performance. Always consult with a professional installer for site-specific recommendations.