iHEAT 18.5kW (1Ph) Monobloc Air Source Heat Pump
Natural Refrigerant R290 · A+++ Rated
The iHEAT 18.5kW is Karnot's highest-output residential model, delivering 19% more capacity than the 15.5kW. Ideal for large homes, HMOs, and light commercial properties with high thermal loads. Full inverter R290 technology, 75°C output, 16.8kW cooling, and iSAVE™ AI monitoring — all in one monobloc unit.
Integrated iSAVE™ AI Platform
Blockchain-Verified Carbon Monitoring & Grid Optimisation
Carbon Credit Monetisation
Blockchain-verified emissions data enables automatic generation and sale of carbon credits, creating recurring revenue streams from your heat pump operations.
Virtual Power Plant Ready
Participate in demand response programmes and utility partnerships, earning incentives by shifting thermal loads during peak pricing periods.
Real-Time Performance Optimisation
Cloud-based fluid dynamics models continuously tune system parameters, maximising COP and reducing operational costs by 15–25%.
Predictive Maintenance Analytics
Machine learning algorithms detect anomalies and predict component failures weeks in advance, reducing downtime and maintenance costs by up to 40%.
Solar PV Self-Consumption
Intelligent thermal storage optimisation maximises use of on-site solar generation, reducing grid dependency and accelerating ROI on renewable installations.
Tamper-Proof Data Integrity
Integrated UPS and cryptographic verification ensure continuous, auditable emissions tracking for regulatory compliance and credit certification.
Revenue Enhancement: iSAVE transforms traditional heat pumps into revenue-generating assets through three channels: carbon credit sales, utility demand response payments, and reduced energy procurement costs. Typical installations see 8–15% additional annual returns beyond energy savings alone.
Key Features at a Glance
75°C Hot Water
High water temperature without auxiliary heating — works with existing radiators for direct gas boiler replacement.
A+++ Efficiency
Top-tier energy rating with R290 GWP of 3 — future-proofed against F-gas regulations and PFAS restrictions.
Whisper Quiet
3Ph variant achieves 42.4 dBA minimum — quieter than a library, meeting even the most stringent planning conditions.
Smart Control
Applica mobile app with real-time monitoring, weather compensation, and multi-zone hydronic management.
SG Ready
Shifts thermal loads to cheapest grid periods, maximising savings with Octopus Agile and similar time-of-use tariffs.
16.8kW Cooling
Powerful summer cooling (EER up to 4.16) when paired with iZONE fan coil units — eligible for the £2,500 cooling grant.
Ideal Applications: Modern Hydronic Systems
The iHEAT 18.5kW is designed for larger hydronic systems — larger homes, HMOs, and light commercial buildings demanding high output with low running costs.
Maximum Energy Efficiency
Water is 3,500× more efficient than air for thermal transfer — localised zoning and reduced fan energy deliver a lower carbon footprint.
Superior Comfort & Air Quality
Silent radiant comfort with stable temperatures and no drafts — a healthier environment than forced-air HVAC.
Architectural Flexibility
Compact water pipes replace bulky air ducts, freeing ceiling plenum space for modern building design.
UK Retrofit & Installation Advantages
Engineered for seamless UK retrofits — works with existing radiators, no underfloor heating or pipework replacements needed.
Use Existing Radiators
75°C output matches gas boiler temperatures — direct swap with no infrastructure changes. Start saving day one.
Lower Installation Costs
40–60% cheaper than low-temp (35°C) system retrofits. No radiator replacements, no underfloor runs needed.
Summer Cooling Ready
iZONE fan coils turn the 18.5kW into a complete climate system — heating, hot water, and cooling in one unit.
Instant Hot Water
Mains-pressure domestic hot water alongside space heating — no separate cylinders or immersion heaters needed.
Boiler Plus Compliant
A+++ efficiency, smart controls, and weather compensation exceed UK Boiler Plus requirements.
MCS & BUS Grant Eligible
MCS certified HP0304. £7,500 BUS grant plus £2,500 cooling grant = up to £10,000 government support.
Retrofit Reality: Unlike 35–55°C systems requiring expensive radiator upgrades, Karnot iHEAT delivers the same water temperatures as a gas boiler — making clean energy transition straightforward, affordable, and immediate for large homes and HMOs.
Warm Homes Plan Grant-Eligible (2026)
iHEAT R290 systems qualify for the universal BUS grant.
iZONE fan coils receive £2,500 for summer cooling capability.
Performance
| Max Heating Output | 18.5 kW |
| Heating COP Range | 4.14 – 5.59 |
| Max Cooling Output | 16.8 kW |
| Cooling EER Range | 3.51 – 4.16 |
| Ambient Operating Range | −25 °C to 45 °C |
Technical Specifications
| Order Reference | CGK060V4P |
| Power Supply | 220–240V / 1Ph / 50–60Hz |
| Max Operating Current | 37.46 A |
| Recommended Breaker | 50 A |
| Compressor | Panasonic Twin Rotary Inverter |
| Pump | Grundfos (R290 Explosion-Proof) |
| Control System | Carel Controller |
| Refrigerant / Charge | R290 / 0.55 kg (GWP 3) |
| Sound Pressure Level | 44.7 – 51 dBA @ 1m |
Dimensions & Weight
| Unit Dimensions (L×W×H) | 1110 × 475 × 1355 mm |
| Net / Gross Weight | 147 kg / 172 kg |
| Cabinet Material | Weather-resistant PP + Galvanised Metal + ABS |
Advanced Technology & Design
High-Efficiency Components
Electronic Expansion Valve (EEV) technology combined with a BLDC inverter compressor delivers superior Seasonal COP and lower power consumption across the full operating range.
Innovative Cabinet Design
The ABS blister front panel features 45° stripe styling and an aerodynamically optimised spiral mesh cover. Weather-resistant PP construction ensures long-term outdoor durability.
Superior Evaporator
Frost-flow evaporator design shortens defrost cycles. Increased fin area allows a 20% fan speed reduction vs R32 units, boosting efficiency and reducing noise — critical for planning-sensitive installations.
Intelligent Control
Intuitive Management
Intelligent touchscreen and Wi-Fi control via the Applica mobile app — real-time status, weather compensation, and remote management from anywhere.
Primary Software Functions:
- Manages primary water (heating/cooling) and domestic hot water (DHW).
- Modulated, high-efficiency control of fans, pumps, and EEVs.
- Intelligent operating limits and optimised low-load compressor management.
- Automated safety functions: Defrost, Antifreeze, and Anti-Legionella cycles.
- Alarm system with integrated troubleshooting guides.
Hydronic System Management:
- Climate curve management for weather compensation.
- Circulation pump activation for up to three distinct zones.
- Specialised screed-drying function for new construction.