Ideal Heating · An established brand in the UK. 168 codes across 2 product families, each taken from the manufacturer’s manuals. Ideal Heating technical support ↗
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168 codes
| Code | Meaning | Stops? | Homeowner check? |
|---|---|---|---|
| 7 | No heat pump starts exceeded | Not stated | Yes |
| 10 | Outside Sensor Fault | Not stated | Yes |
| 26 | Header Thermistor Fault (used for Cascade Systems) | Not stated | Yes |
| 33 | Flow Thermistor (Indoor) Fault | Not stated | Yes |
| 44 | Return Thermistor Fault | Not stated | Yes |
| 50 | DHW Thermistor Fault | Not stated | Yes |
| 60 | Room Stat 1 Fault | Not stated | Yes |
| 65 | Room Stat 2 Fault | Not stated | Yes |
| 81 | LPB short-circuit/comm Fault | Not stated | Yes |
| 82 | LPB address collision Fault | Not stated | Yes |
| 83 | BSB short circuit Fault | Not stated | Yes |
| 84 | BSB address collision | Not stated | Yes |
| 100 | 2 clock time masters Fault | Not stated | Yes |
| 102 | Clock without backup Fault | Not stated | Yes |
| 106 | Source Temp too low | Not stated | Yes |
| 126 | 7093 DHW Setpt Fault | Not stated | Yes |
| 127 | Anti-Legionella Temp' Fault | Not stated | Yes |
| 134 | Re-occurring Heat Pump Fault | Yes | Yes |
| 146 | Configuration error | Not stated | Yes |
| 171 | Alarm contact 1 active Fault | Not stated | Yes |
| 366 | Room temp sensor Fault | Not stated | Yes |
| 369 | External Fault | Not stated | Yes |
| 370 | Heat Pump fault (outdoor unit) - with F-sub-code | Yes | Yes |
| 370-F0 | Heat Pump fault: No outdoor connection fault | Yes | Yes |
| 370-F1 | Heat Pump fault: No outdoor connection fault | Yes | Yes |
| 370-F2 | Heat Pump fault: Outdoor HX thermistor fault | Not stated | Yes |
| 370-F3 | Heat Pump fault: Heat pump inverter fault | Yes | Yes |
| 370-F4 | Heat Pump fault: Outdoor electrical filtering fault | Not stated | Yes |
| 370-F5 | Heat Pump fault: Outdoor discharge thermistor | Not stated | Yes |
| 370-F6 | Heat Pump fault: Compressor thermistor fault | Not stated | Yes |
| 370-F7 | Heat Pump fault: Outdoor intermediate HX thermistor | Not stated | Yes |
| 370-F8 | Heat Pump fault: Outdoor outlet HX thermistor | Not stated | Yes |
| 370-F9 | Heat Pump fault: Heat Pump defrost thermistor fault | Not stated | Yes |
| 370-F10 | Heat Pump fault: Outdoor heatsink thmr fault | Not stated | Yes |
| 370-F11 | Heat Pump fault: outdoor PFC thermistor fault | Not stated | Yes |
| 370-F12 | Heat Pump fault: Outdoor exp valve thmr | Not stated | Yes |
| 370-F13 | Heat Pump fault: Outdoor electrical error | Not stated | Yes |
| 370-F14 | Heat Pump fault: outdoor pressure sensor fault | Yes | Yes |
| 370-F15 | Heat Pump fault: Current Trip | Yes | Yes |
| 370-F16 | Heat Pump fault: Heat pump compressor fault | Yes | Yes |
| 370-F17 | Heat Pump fault: Heat pump fan fault | Yes | Yes |
| 370-F18 | Heat Pump fault: Outdoor discharge temp' | Yes | Yes |
| 370-F19 | Heat Pump fault: Compressor temperature fault | Yes | Yes |
| 370-F20 | Heat Pump fault: Outdoor low pressure | Yes | Yes |
| 370-F21 | Heat Pump fault: Outdoor power supply fault | Not stated | Yes |
| 370-F22 | Heat Pump fault: No outdoor connection | Yes | Yes |
| 370-F23 | Heat Pump fault: Hydraulic HX temperature | Yes | Yes |
| 370-F24 | Heat Pump fault: Primary Circulation Pump | Yes | Yes |
| 370-F25 | Heat Pump fault: Evaporator Outlet Thermistor | Not stated | Yes |
| 370-F26 | Heat Pump fault: Outdoor Power Supply | Not stated | Yes |
| 370-F27 | Heat Pump fault: No water flow fault | Yes | Yes |
| 385 | Low Mains Voltage Fault | Not stated | Yes |
| 489 | No Cascade Master Fault | Not stated | Yes |
| 490 | No outdoor connection Fault | Yes | Yes |
| 499 | No outdoor connection Fault | Yes | Yes |
| 506 | Boiler no temp' rise Fault | Not stated | Yes |
| 516 | No outdoor connection Fault | Yes | Yes |
| C7 | Inverter Error | Yes | Yes |
| E0 | No Water Flow, through Outdoor Unit, 10 times in succession | Yes | Yes |
| E1 | Live and Neutral reversed | Not stated | Yes |
| E2 | No connection Outdoor PCB to User Interface | Yes | Yes |
| E3 | Header Thermistor (T1) Error (for Hybrid/Cascade) | Not stated | Yes |
| E4 | DHW Cylinder Thermistor (T5) Error | Not stated | Yes |
| E5 | Outdoor Unit, Air to Refrigerant Heat Exchanger Outlet Thermistor (T3) Error | Not stated | Yes |
| E6 | Outdoor Sensor within Outdoor Unit (T4) Error | Not stated | Yes |
| E8 | No Water Flow, through Outdoor Unit | Yes | Yes |
| E9 | Compressor Refrigerant Return Thermistor (Th) Error | Not stated | Yes |
| EA | Discharge Thermistor (Tp) Error | Not stated | Yes |
| Ed | Outdoor Unit, Return Thermistor (Tw_in) Error | Not stated | Yes |
| F1 | Inverter Error | Yes | Yes |
| FC1 | Outdoor Unit, Air to Refrigerant Heat Exchanger Outlet Thermistor Error | Not stated | Yes |
| H0 | No connection Outdoor PCB to Indoor PCB | Yes | Yes |
| H1 | No connection Outdoor PCB to Inverter PCB | Yes | Yes |
| H2 | Plate Heat Exchanger Outlet Refrigerant Thermistor (T2) Error | Not stated | Yes |
| H3 | Plate Heat Exchanger Inlet Refrigerant Thermistor (T2B) Error | Not stated | Yes |
| H4 | Inverter High Current (L1E/L11/L12) 3 times within 60mins | Yes | Yes |
| H6 | Fan Error | Yes | Yes |
| H7 | Mains High Voltage or Low Voltage Error | Not stated | Yes |
| H8 | High Pressure Sensor Error | Not stated | Yes |
| H9 | Central Heating Zone 2 Thermistor Fault | Not stated | Yes |
| HA | Outdoor Unit, Flow Thermistor (Tw_out) Error | Not stated | Yes |
| Hb | High Flow/Return Differential, 3 times in succession and Flow Temperature <7C | Yes | Yes |
| Hd | No connection Master Heat Pump to Slave Heat Pump | Not stated | Yes |
| HF | Inverter not matched to Outdoor PCB dip switch setting | Yes | Yes |
| HH | 10 Fan Errors in 2 hours | Yes | Yes |
| J2E | Inverter High Temperature | Yes | Yes |
| J3E | Inverter Error | Yes | Yes |
| J5E | Compressor Error | Yes | Yes |
| J6E | Inverter Error | Yes | Yes |
| J11 | Inverter High Current | Yes | Yes |
| J12 | Inverter High Current | Yes | Yes |
| J31 | Inverter Error | Yes | Yes |
| J32 | Inverter Error | Yes | Yes |
| J43 | Inverter Error | Yes | Yes |
| J45 | Wrong Fan Motor Fitted | Yes | Yes |
| J46 | Inverter Error | Yes | Yes |
| J47 | Inverter Error | Yes | Yes |
| J52 | Compressor Stall Error | Yes | Yes |
| J61 | Fan Connections Short Circuit | Yes | Yes |
| J65 | Inverter Error | Yes | Yes |
| L1E | Inverter High Current | Yes | Yes |
| L2E | Inverter High Temperature | Yes | Yes |
| L3E | Inverter Error | Yes | Yes |
| L5E | Compressor Start Error | Yes | Yes |
| L6E | Inverter Error | Yes | Yes |
| L11 | Inverter High Current | Yes | Yes |
| L12 | Inverter High Current | Yes | Yes |
| L31 | Inverter Error | Yes | Yes |
| L32 | Inverter Error | Yes | Yes |
| L34 | Inverter Error | Yes | Yes |
| L43 | Inverter Error | Yes | Yes |
| L45 | Wrong Fan Fitted | Yes | Yes |
| L46 | Inverter Error | Yes | Yes |
| L47 | Inverter Error | Yes | Yes |
| L52 | Compressor Stall Error | Yes | Yes |
| L61 | Short Circuit to Compressor Terminals | Yes | Yes |
| L65 | Inverter Error | Yes | Yes |
| LB7 | Inverter Error | Yes | Yes |
| LBC | Inverter Error | Yes | Yes |
| LBE | High Pressure Switch Operated | Yes | Yes |
| LC1 | Inverter Error | Yes | Yes |
| LC2 | Inverter Error | Yes | Yes |
| LC3 | Inverter Error | Yes | Yes |
| LC4 | Inverter Error | Yes | Yes |
| LC5 | Inverter Error | Yes | Yes |
| LC6 | Inverter Error | Yes | Yes |
| LC7 | Inverter Error | Yes | Yes |
| LC8 | Inverter Error | Yes | Yes |
| LC9 | Inverter High Temperature | Yes | Yes |
| LCA | Inverter High Current | Yes | Yes |
| LCB | Inverter Error | Yes | Yes |
| LCD | Inverter Error | Yes | Yes |
| LCE | Inverter High Current | Yes | Yes |
| LED-9B | Circulation pump error | Yes | Yes |
| LED-10x11 | Heat sink temp. error | Yes | Yes |
| LED-11-forward | Serial communication error (serial forward transfer error) - outdoor unit cannot receive hydraulic unit signal | Yes | Yes |
| LED-11-reverse | Serial communication error (serial reverse transfer error) - hydraulic unit cannot receive outdoor unit signal | Yes | Yes |
| LED-23 | Combination error | Yes | Yes |
| LED-32 | Outdoor unit PCB model information error | Not stated | Yes |
| LED-62 | Outdoor unit main PCB error / communication error in outdoor unit | Not stated | Yes |
| LED-63 | Inverter error | Yes | Yes |
| LED-65 | IPM error | Yes | Yes |
| LED-71 | Discharge temp. sensor error | Not stated | Yes |
| LED-72 | Compressor temp. sensor error | Not stated | Yes |
| LED-73 | Heat-exchange middle temp. sensor error / outdoor unit heat-exchange liquid (outlet) temp. sensor error | Not stated | Yes |
| LED-74 | Outdoor temp. sensor error | Not stated | Yes |
| LED-77 | Heat sink temp. sensor error | Not stated | Yes |
| LED-78 | Electric expansion valve sensor error | Not stated | Yes |
| LED-79 | Water outlet temp. sensor error | Not stated | Yes |
| LED-84 | Current sensor error | Not stated | Yes |
| LED-86-HP-switch | High pressure switch error | Yes | Yes |
| LED-86-pressure-sensor | Pressure sensor error | Not stated | Yes |
| LED-94 | Trip detection | Yes | Yes |
| LED-95 | Compressor motor control error (compressor rotor position detection error) | Yes | Yes |
| LED-97 | Outdoor unit fan motor 1 error | Yes | Yes |
| LED-A1 | Discharge temp. error | Yes | Yes |
| LED-A3 | Compressor temp. error | Yes | Yes |
| LED-A5 | Low pressure error | Yes | Yes |
| LED-AE | Low water flow error (no or insufficient water flow rate) | Yes | Yes |
| P0 | Low Pressure Error | Yes | Yes |
| P1 | High Pressure Switch Operated | Yes | Yes |
| P3 | Overcurrent Protection Error | Yes | Yes |
| P4 | Compressor Discharge Temperature High | Yes | Yes |
| P5 | High Flow/Return Differential | Not stated | Yes |
| P21 | Low Pressure Sensor Error | Not stated | Yes |
| P27 | High Pressure Sensor and Low Pressure Sensor Wiring Reversed | Not stated | Yes |
| Pd | Condensing Temperature High | Not stated | Yes |
| PP | High Flow/Return Differential | Not stated | Yes |