Ideal
The Ideal HP290 is an R290 monobloc heat pump offering outputs from 4.5 to 14 kilowatts. It achieves flow temperatures of 75 degrees Celsius and a SCOP of 5.07 at 35 degrees.
The Ideal HP290_Installation_Maintenance_Manual covers the HP290 Monobloc range of air-source heat pumps, spanning outputs from 4.5kW to 14kW. Utilizing R290 refrigerant with a GWP of 3, these units provide high-temperature heating up to 75°C. This technical reference details the 4.5kW model's SCOP of 5.07, installation clearances, and comprehensive fault codes for UK heating engineers and installers.
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Full technical specifications extracted from the manufacturer brochure. Empty sections are hidden.
At the end of each 12-month period after commissioning, the Heat Pump must be serviced by a suitable competent heat pump engineer in accordance with the process in the manufacturer’s instructions.
The Ideal HP290 MONOBLOC HEAT PUMP SYSTEM represents a significant shift toward natural refrigerants in the UK domestic market. By employing R290 (propane), which has a Global Warming Potential (GWP) of just 3, the unit achieves high flow temperatures up to 75°C, making it suitable for properties where traditional low-temperature emitters may not be feasible. The range is versatile, offering six variants from the 4.5kW entry model up to a 14kW unit for larger heat-loss requirements.
Efficiency is a core metric for the HP290. The 4.5kW model delivers a Coefficient of Performance (COP) of 5.15 at A7/W35 conditions and maintains a Seasonal Coefficient of Performance (SCOP) of 5.07 at 35°C. Even at higher flow temperatures of 55°C, the SCOP remains efficient at 3.79. These figures are supported by an inverter-driven compressor that modulates output based on demand, reducing cycling and improving longevity. The system is designed for monobloc installation, meaning the refrigerant circuit is entirely self-contained within the outdoor housing, simplifying the hydraulic connection via 22mm pipework.
Physically, the 4.5kW outdoor unit measures 717mm in height, 1299mm in width, and 351mm in depth, with a weight of 90kg. Installation requires specific clearances to ensure adequate airflow: 500mm at the sides, 1000mm at the front, and 300mm behind the unit. Electrical requirements for the 4.5kW variant include a 230V single-phase supply with a recommended 20A MCB rating. The unit is Smart Grid ready and supports Modbus communication, integrating with Ideal’s Halo Lite RF controls. For domestic hot water, the HP290 is compatible with Ideal’s range of pre-plumbed cylinders, including single and twin-zone options.
Maintenance is mandatory every 12 months to maintain warranty validity. Service procedures include checking the evaporator for debris, cleaning the fan assembly, and verifying the glycol and inhibitor levels. The control system features a sophisticated diagnostic interface. For instance, an E0 error indicates a persistent lack of water flow, often caused by air in the system or dirty filters, while an H4 code signals a high-current inverter fault requiring compressor resistance checks. This technical documentation ensures engineers can accurately diagnose and resolve issues using the onboard User Interface.
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/hp290-6-kw#fault-c7 to jump straight to the entry.
| Code | Meaning | Details |
|---|---|---|
| C7 | Inverter Error Show causes & actionsEngineer action Set power supply to OFF. Wait 10 minutes. Check 240V AC mains wiring to Inverter PCB. Check 7-way Modbus wiring. Replace Inverter PCB if defective. | Details |
| E0Lockout | No Water Flow, through Outdoor Unit, 10 times in succession Show causes & actionsLikely causes
Engineer action Check pump feedback. Verify 240V AC at pump. Check low-voltage wiring. Refill and vent system. Check supply voltage (170-253V). Open ball valves. Clean filters. Check flow switch continuity. Reset procedure Turn power off and on to clear the fault once root cause is corrected. | Details |
| E1 | Live and Neutral reversed Show causes & actionsLikely causes
Engineer action Check XT1 connector wiring: L=Brown, N=Blue, Earth=Yellow/Green. Replace Outdoor PCB if fault persists. | Details |
| E2 | No connection Outdoor PCB to User Interface Show causes & actionsLikely causes
Engineer action Check two-way wiring between units. Check wiring from Indoor PCB to User Interface. Replace User Interface or Outdoor PCB. | Details |
| E3 | Header Thermistor (T1) Error (for Hybrid/Cascade) Show causes & actionsLikely causes
Engineer action Check UI settings. Connect Header Thermistor. Check wiring to Outdoor PCB. Check resistance (30k-500k ohms). Replace thermistor or Outdoor PCB. | Details |
| E4 | DHW Cylinder Thermistor (T5) Error Show causes & actionsLikely causes
Engineer action Check DHW settings. Connect thermistor. Check wiring to Indoor PCB CN13. Check resistance (30k-500k ohms). Replace thermistor or Indoor PCB. | Details |
| E5 | Outdoor Unit, Air to Refrigerant Heat Exchanger Outlet Thermistor (T3) Error Show causes & actionsEngineer action Check connection to Outdoor PCB. Check resistance (6k-100k ohms). Replace thermistor or Outdoor PCB. | Details |
| E6 | Outdoor Sensor within Outdoor Unit (T4) Error Show causes & actionsEngineer action Check connection to Outdoor PCB. Check resistance (6k-100k ohms). Replace thermistor or Outdoor PCB. | Details |
| E8 | No Water Flow, through Outdoor Unit Show causes & actionsLikely causes
Engineer action Check valves, strainers, and pressure (1-1.5 bar). Bleed air. Cycle power at rotary isolator. | Details |
| E9 | Compressor Refrigerant Return Thermistor (Th) Error (E9) Show causes & actionsEngineer action Check connection to Outdoor PCB. Check resistance (6k-100k ohms). Replace thermistor (T4) or Outdoor PCB. | Details |
| EA | Discharge Thermistor (Tp) Error Show causes & actionsEngineer action Check connection to Outdoor PCB. Check resistance (35k-500k ohms). Replace thermistor or Outdoor PCB. | Details |
| Ed | Outdoor Unit, Return Thermistor (Tw_in) Error Show causes & actionsEngineer action Check connection to Outdoor PCB. Check resistance (35k-500k ohms). Replace thermistor or Outdoor PCB. | Details |
| F1 | Inverter Error Show causes & actionsEngineer action Refer to generic Inverter Error procedure (9.1.1). | Details |
| H0 | No connection Outdoor PCB to Indoor PCB Show causes & actionsLikely causes
Engineer action Check 3-way wiring between Outdoor PCB and Indoor Control Box. Verify T1/T2 and X/HA X/HB connections. Replace Indoor or Outdoor PCB. | Details |
| H1 | No connection Outdoor PCB to Inverter PCB Show causes & actionsLikely causes
Engineer action Check mains supply to Inverter PCB. Check low-voltage cable from Outdoor PCB. Test Inverter with tester. Replace Inverter or Outdoor PCB. | Details |
| H2 | Plate Heat Exchanger Outlet Refrigerant Thermistor (T2) Error Show causes & actionsEngineer action Check connection to Outdoor PCB. Check resistance (30k-500k ohms). Replace thermistor (T2) or Outdoor PCB. | Details |
| H3 | Plate Heat Exchanger Inlet Refrigerant Thermistor (T2B) Error Show causes & actionsEngineer action Check connection to Outdoor PCB. Check resistance (30k-500k ohms). Replace thermistor or Outdoor PCB. | Details |
| H4Lockout | Inverter High Current (L1E/L11/L12) 3 times within 60mins Show causes & actionsLikely causes
Engineer action Measure compressor terminal resistances (must be >10 ohms). Replace compressor or Inverter. | Details |
| H6 | Fan Error Show causes & actionsLikely causes
Engineer action Check wiring. Check terminal resistances (Red-White, Red-Black, White-Black >10 ohms). Replace Fan or Inverter. | Details |
| H7 | Mains High Voltage or Low Voltage Error Show causes & actionsLikely causes
Engineer action Check mains voltage. Contact electricity provider. Replace Inverter PCB if voltage is correct. | Details |
| H8 | High Pressure Sensor Error Show causes & actionsLikely causes
Engineer action Check wiring to Outdoor PCB. Check voltage (0.5-4.5V DC). Replace sensor or Outdoor PCB. | Details |
| H9 | Central Heating Zone 2 Thermistor Fault Show causes & actionsLikely causes
Engineer action Check thermistor connection. Check wiring to Indoor PCB CN13. Check resistance (30k-500k ohms). Replace thermistor or Indoor PCB. | Details |
| HA | Outdoor Unit, Flow Thermistor (Tw_out) Error Show causes & actionsEngineer action Check connection to Outdoor PCB. Check resistance (30k-500k ohms). Replace thermistor or Outdoor PCB. | Details |
| HbLockout | High Flow/Return Differential, 3 times in succession and Flow Temperature <7°C Show causes & actionsLikely causes
Engineer action Check flow/return pipes. Verify thermistor installation. Check 4-way valve wiring and 240V supply. Replace 4-way valve or Outdoor PCB. | Details |
| Hd | No connection Master Heat Pump to Slave Heat Pump Show causes & actionsLikely causes
Engineer action Check inter-unit wiring. Verify S3 dip switches are unique. Check SW9 position. Ensure time difference between pumps is <1 min. | Details |
| HF | Inverter not matched to Outdoor PCB dip switch setting Show causes & actionsLikely causes
Engineer action Set S5 switches 1-4 to OFF. Set S6 switches 1-4 to unit capacity. Replace Outdoor or Inverter PCB. | Details |
| HHLockout | 10 Fan Errors in 2 hours Show causes & actionsEngineer action Refer to H6 Fan Error procedure. | Details |
| P0 | Low Pressure Error Show causes & actionsLikely causes
User action Remove snow/ice from unit. Engineer action Clean heat exchanger. Check clearances. Verify fan operation. Recharge refrigerant. Check EEV wiring and operation. Replace sensor or Outdoor PCB. | Details |
| P1Lockout | High Pressure Switch Operated Show causes & actionsLikely causes
Engineer action Check for water flow (E0/E8). Clean pipes/filters. Check pressure switch wiring. Verify P1/P2 pressures (>3.5MPa). Repressurise circuit or replace switch/Inverter PCB. Reset procedure Reset lockout manually. | Details |
| P3 | Overcurrent Protection Error Show causes & actionsLikely causes
Engineer action Check mains supply (207-253V). Test Inverter. Check compressor wiring (U, V, W). Check compressor resistances (>10 ohms). Replace compressor or Inverter. Reset procedure Reset lockout. | Details |
| P4 | Compressor Discharge Temperature High Show causes & actionsLikely causes
Engineer action Check Tp thermistor resistance. Verify flow/return thermistor installation. Check P1 pressure against Table 24. Repressurise refrigerant or replace Outdoor PCB. | Details |
| P5 | High Flow/Return Differential Show causes & actionsEngineer action Refer to Hb fault procedure. | Details |
| P21 | Low Pressure Sensor Error Show causes & actionsLikely causes
Engineer action Check wiring to Outdoor PCB. Check voltage (0.5-4.5V DC). Replace sensor or Outdoor PCB. | Details |
| P27 | High Pressure Sensor and Low Pressure Sensor Wiring Reversed Show causes & actionsLikely causes
Engineer action Verify wiring against diagrams. Correct sensor connections. Replace Outdoor PCB. | Details |
| Pd | Condensing Temperature High Show causes & actionsLikely causes
Engineer action Clean heat exchanger. Check fan operation. Verify EEV operation. Replace sensor or Outdoor PCB. | Details |
| PP | High Flow/Return Differential Show causes & actionsEngineer action Refer to Hb fault procedure. | Details |
| FC1 | Outdoor Unit, Air to Refrigerant Heat Exchanger Outlet Thermistor Error Show causes & actionsEngineer action Refer to E5 fault procedure. | Details |
| 3-way Valve does not operate | 3-way Valve does not operate and No DHW Show causes & actionsLikely causes
User action Check DHW timer and target temperature. Engineer action Check 240V at PCB terminal 3_1ON. Check Overheat Stat continuity. Check 240V at valve connection. Replace valve or Indoor PCB. | Details |
| Anti-Legionella does not operate | Anti-Legionella function failure Show causes & actionsLikely causes
Engineer action Check 240V at Contactor Coil and L-in/L-out. Check 240V to Immersion Heater. Ensure thermostat is set to MAX. Replace heater or Control Box. | Details |
| No Display | Control Box display is blank Show causes & actionsLikely causes
User action Check mains power is ON. Engineer action Verify 240V at Outdoor Unit. Check two-way wiring from Outdoor to Indoor unit. Check wiring to UI. Replace UI or Outdoor PCB. | Details |
Patterns that group across the manufacturer's fault-code table. Each entry links to the full code listing further down the page.
Engineer: Check pump feedback. Verify 240V AC at pump. Check low-voltage wiring. Refill and vent system. Check supply voltage (170-253V). Open ball valves. Clean filters. Check flow switch continuity.
Triggered by fault code E0.
Engineer: Measure compressor terminal resistances (must be >10 ohms). Replace compressor or Inverter.
Triggered by fault code H4.
Engineer: Check flow/return pipes. Verify thermistor installation. Check 4-way valve wiring and 240V supply. Replace 4-way valve or Outdoor PCB.
Triggered by fault code Hb.
Common questions from engineers and homeowners about the Ideal HP290 6 kW.
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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 30 April 2026.
Engineer: Refer to H6 Fan Error procedure.
Triggered by fault code HH.
Engineer: Check for water flow (E0/E8). Clean pipes/filters. Check pressure switch wiring. Verify P1/P2 pressures (>3.5MPa). Repressurise circuit or replace switch/Inverter PCB.
Triggered by fault code P1.