Ideal
The Ideal Logic Air Monobloc Heat Pump system is an air-source heat pump available in 4kW, 5kW, 8kW, and 10kW capacities, offering a SCOP of 5.19 at 35°C.
The Ideal LOGIC AIR MONOBLOC HEAT PUMP SYSTEM is an air-source heat pump designed for UK domestic heating and hot water applications. Available in 4kW, 5kW, 8kW, and 10kW variants, this monobloc unit utilises R32 refrigerant. It offers a maximum flow temperature of 60°C and operates down to -20°C outdoor temperatures. This page provides technical specifications, performance data, and fault codes for installation and maintenance professionals, as well as homeowners seeking detailed product information.
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Full technical specifications extracted from the manufacturer brochure. Empty sections are hidden.
Serviced in line with the manufacturers’ recommendations, at least annually.
The Ideal LOGIC AIR MONOBLOC HEAT PUMP SYSTEM is an inverter-type air-source monobloc heat pump, available in models ranging from 4kW to 10kW nominal capacity. It operates using R32 refrigerant, which has a GWP of 675 and a charge of 1.47kg. Performance data indicates a COP of 5.34 at A7W35 and a seasonal SCOP of 5.19 at 35°C, making it suitable for various heating demands. The system can achieve a maximum flow temperature of 60°C and maintain operation in outdoor temperatures as low as -20°C.
Installation considerations include an outdoor unit measuring 1190mm (H) x 1175mm (W) x 600mm (D) and weighing 110kg. The indoor unit, which includes a 287L DHW cylinder, has dimensions of 2128mm (H) x 705mm (W) x 780mm (D) and weighs 437.5kg. A minimum water flow rate of 14.5 lpm is required, and both a buffer tank and volumiser are necessary for proper hydraulic function. The system features hot gas auto-defrost and comes with a standard 1-year warranty, extendable with annual servicing.
Every fault code listed in the manufacturer brochure, with likely causes and engineer actions. Each code has a permalink — paste a URL like https://www.boilertag.com/heat-pumps/ideal/4kw-logic-air#fault-10 to jump straight to the entry.
| Code | Meaning | Details |
|---|---|---|
| 10 | Outside Sensor Fault Show causes & actionsEngineer action Go to: 9.1.2 Outside Sensor Fault | Details |
| 26 | Header Thermistor Fault Show causes & actionsEngineer action Go to: 9.1.3 Header Thermistor Fault (used for Cascade Systems) | Details |
| 33 | Flow Thermistor (Indoor) Fault Show causes & actionsEngineer action Go to: 9.1.5 Flow Thermistor (Indoor) Fault | Details |
| 44 | Return Thermistor Fault Show causes & actionsEngineer action Go to: 9.1.6 Return Thermistor Fault | Details |
| 50 | DHW Thermistor Fault Show causes & actionsEngineer action Go to: 9.1.7 DHW Thermistor Fault | Details |
| 60 | Room Stat 1 Fault Show causes & actionsEngineer action Go to: 9.1.8 Room Thermostat 1 Fault | Details |
| 65 | Room Stat 2 Fault Show causes & actionsEngineer action Go to: 9.1.9 Room Thermostat 2 Fault | Details |
| 81 | LPB short-circuit/comm Fault Show causes & actionsEngineer action Go to: 9.1.10 LPB (Cascade) Short-Circuit/Communication Fault | Details |
| 82 | LPB address collision Fault Show causes & actionsEngineer action Go to: 9.1.11 LPB (Cascade) Address Collision Fault | Details |
| 83 | BSB short circuit Fault Show causes & actionsEngineer action Go to: 9.1.12 BSB Short Circuit Fault | Details |
| 84 | BSB address collision Show causes & actionsEngineer action Go to: 9.1.13 BSB Address Collision Fault | Details |
| 100 | 2 clock time masters Fault Show causes & actionsEngineer action Go to: 9.1.14 2 Clock Time Masters Fault | Details |
| 102 | Clock without backup Fault Show causes & actionsEngineer action Go to: 9.1.15 Clock Without Back-up Fault | Details |
| 106 | Source Temp too low Show causes & actionsEngineer action Go to: 9.1.16 Source temp too low | Details |
| 126 | 7093 DHW Setpt Fault Show causes & actionsEngineer action Go to: 9.1.17 7093 DHW Setpoint Fault | Details |
| 127 | Anti-Legionella Temp’ Fault Show causes & actionsEngineer action Go to: 9.1.18 Anti-Legionella Temperature Fault | Details |
| 134 | Re-occurring Heat Pump Fault Show causes & actionsEngineer action Go to: 9.1.19 Re-occurring Heat Pump Fault | Details |
| 146 | Configuration error Show causes & actionsEngineer action Go to: 9.1.19 Re-occurring Heat Pump Fault | Details |
| 171 | Alarm contact 1 active Fault Show causes & actionsEngineer action Go to: 9.1.21 Alarm Contact 1 Active Fault | Details |
| 366 | Room temp sensor Fault Show causes & actionsEngineer action Go to: 9.1.22 Room Temperature Sensor Fault | Details |
| 369 | External Fault Show causes & actionsEngineer action Go to: 9.1.23 External Fault | Details |
| 385 | Low Mains Voltage Fault Show causes & actionsEngineer action Go to: 9.1.24 Low Mains Voltage Fault | Details |
| 489 | No Cascade Master Fault Show causes & actionsEngineer action Go to: 9.1.25 No Cascade Master Fault | Details |
| 490 | No outdoor connection Fault Show causes & actionsEngineer action Go to: 9.1.26 No Outdoor Connection Fault | Details |
| 499 | No outdoor connection Fault Show causes & actionsEngineer action Go to: 9.1.26 No Outdoor Connection Fault | Details |
| 506 | Boiler no temp’ rise Fault Show causes & actionsEngineer action Go to: 9.1.27 Back-up Boiler no Temperature Rise Fault | Details |
| 516 | No outdoor connection Fault Show causes & actionsEngineer action Go to: 9.1.26 No Outdoor Connection Fault | Details |
| 7 | No heat pump starts exceeded Show causes & actionsEngineer action Go to: 9.1.28 Number of Heat Pump Starts Exceeded | Details |
| No Hot Water | No Hot Water Show causes & actionsEngineer action Go to: 9.1.30 No Hot Water but Central Heating works OK | Details |
| No Central Heating | No Central Heating Show causes & actionsEngineer action Go to: 9.1.29 No Central Heating but Hot Water works OK | Details |
| No Display | No Display Show causes & actionsEngineer action Go to: 9.1.31 No Display on Indoor Unit | Details |
| 370 | Heat Pump fault:- F0 No outdoor connection fault Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 1 | Details |
| 370 | Heat Pump fault:- F1 No outdoor connection fault Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 2 | Details |
| 370 | Heat Pump fault:- F2 Outdoor HX thermistor fault Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 15 | Details |
| 370 | Heat Pump fault:- F3 Heat pump inverter fault Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 6 | Details |
| 370 | Heat Pump fault:- F4 Outdoor electrical filtering fault Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 7 | Details |
| 370 | Heat Pump fault:- F5 Outdoor discharge thermistor Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 7 | Details |
| 370 | Heat Pump fault:- F6 Compressor thermistor fault Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 8 | Details |
| 370 | Heat Pump fault:- F7 Outdoor intermediate HX thermistor Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 9 | Details |
| 370 | Heat Pump fault:- F8 Outdoor outlet HX thermistor Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 13 | Details |
| 370 | Heat Pump fault:- F9 Heat Pump defrost thermistor fault Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 12 | Details |
| 370 | Heat Pump fault:- F10 Outdoor heatsink thmr fault Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 11 | Details |
| 370 | Heat Pump fault:- F11 outdoor PFC thermistor fault Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 25 | Details |
| 370 | Heat Pump fault:- F12 Outdoor exp valve thmr Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 12 | Details |
| 370 | Heat Pump fault:- F13 Outdoor electrical error Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 16 | Details |
| 370 | Heat Pump fault:- F14 outdoor pressure sensor fault Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 15-2 | Details |
| 370 | Heat Pump fault:- F15 Current Trip Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 16 | Details |
| 370 | Heat Pump fault:- F16 Heat pump compressor fault Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 17 | Details |
| 370 | Heat Pump fault:- F17 Heat pump fan fault Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 18 | Details |
| 370 | Heat Pump fault:- F18 Outdoor discharge temp’ Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 20 | Details |
| 370 | Heat Pump fault:- F19 Compressor temperature fault Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 21 | Details |
| 370 | Heat Pump fault:- F20 Outdoor low pressure Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 22 | Details |
| 370 | Heat Pump fault:- F21 Outdoor power supply fault Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 25 | Details |
| 370 | Heat Pump fault:- F22 No outdoor connection Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 1 & 2 | Details |
| 370 | Heat Pump fault:- F23 Hydraulic HX temperature Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 15 | Details |
| 370 | Heat Pump fault:- F24 Primary Circulation Pump Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 19 | Details |
| 370 | Heat Pump fault:- F25 Evaporator Outlet Thermistor Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 15 | Details |
| 370 | Heat Pump fault:- F26 Outdoor Power Supply Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 26 | Details |
| 370 | Heat Pump fault:- F27 No water flow fault Show causes & actionsEngineer action Scan QR code and go to section: Troubleshooting 24 | Details |
Patterns that group across the manufacturer's fault-code table. Each entry links to the full code listing further down the page.
Engineer: Go to: 9.1.2 Outside Sensor Fault
Triggered by fault code 10.
Engineer: Go to: 9.1.3 Header Thermistor Fault (used for Cascade Systems)
Triggered by fault code 26.
Engineer: Go to: 9.1.5 Flow Thermistor (Indoor) Fault
Triggered by fault code 33.
Engineer: Go to: 9.1.6 Return Thermistor Fault
Triggered by fault code 44.
Engineer: Go to: 9.1.7 DHW Thermistor Fault
Triggered by fault code 50.
Common questions from engineers and homeowners about the Ideal 4kW Logic Air.
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Specifications on this page are extracted from the manufacturer brochure. Always cross-check against the latest datasheet before commissioning or quoting. Last updated 28 June 2026.