What is the Warmflow Zeno_R32_User_Manual?

The Warmflow Zeno_R32_User_Manual is an 8kW to 20kW monobloc air-source heat pump using R32 refrigerant with an ErP rating of A+++ at 35°C. It is designed for UK domestic heating and hot water, featuring DC inverter technology and a maximum flow temperature of 65°C for compatibility with various emitter types.

How do I register a Warmflow Zeno_R32_User_Manual with BoilerTag?

Scan the QR code on the BoilerTag sticker after installation to register the unit. Confirm the model details, which will pre-fill from the appliance catalogue, and record the installation date and your Gas Safe or MCS number. This creates a permanent, public service log for the appliance. The first 12 BoilerTag stickers are free for engineers. Order free BoilerTag stickers from the engineer dashboard.

What refrigerant does the Warmflow Zeno A-Series use?

The Zeno A-Series uses R32 refrigerant with a charge weight of 1.3kg for the 8kW model. R32 is a more environmentally friendly alternative to R410A, offering a lower Global Warming Potential (GWP) and improved heat transfer efficiency. Because it is a monobloc system, the refrigerant is hermetically sealed within the outdoor unit.

Is the Warmflow Zeno A-Series eligible for the Boiler Upgrade Scheme (BUS)?

Yes, the Warmflow Zeno A-Series is MCS certified and eligible for the £7,500 Boiler Upgrade Scheme grant in England and Wales. To qualify for the grant, the installation must be performed by an MCS-accredited installer and meet specific energy efficiency requirements, including a full heat loss calculation for the property.

What does fault code E032 mean on a Warmflow Zeno heat pump?

Fault code E032 indicates a Low Flow Error, meaning there is insufficient water circulation in the heating circuit. Engineers should check the plumbing for blockages or air locks, ensure all valves are fully open, and verify the correct operation of the circulating pump. Cleaning the heating circuit filter is also a recommended step.

What is the maximum flow temperature of the Warmflow Zeno R32?

The maximum flow temperature is 65°C. This high temperature capability allows the heat pump to be used in retrofit scenarios where existing radiators are retained, although system efficiency is significantly higher when operating at lower flow temperatures, such as 35°C for underfloor heating or oversized radiators.

What are the electrical requirements for the Warmflow AS01-R32?

The AS01-R32 (8kW) requires a 230V single-phase supply and a 20A MCB. Larger models in the range require higher ratings, with the 12kW AS02-R32 requiring a 32A MCB and the 20kW AS03-R32 requiring a 40A MCB. All units feature a low startup current of approximately 1A.

How often should a Warmflow Zeno heat pump be serviced?

Service intervals are every 12 months to maintain the 5-year warranty and ensure operational efficiency. The annual service must include an inspection of electrical connections, cleaning the heating circuit filter, checking glycol and inhibitor concentrations with a refractometer, and verifying the operation of all safety devices and motorised valves.

What is the sound level of the Warmflow Zeno A-Series?

The Zeno A-Series has a sound power level of 50 dB(LWA). This relatively low noise profile aids in meeting MCS-020 planning standards for permitted development. The unit also features a Quiet Mode which can be activated via the touchscreen controller to further reduce noise emissions during specific times.

Does the Warmflow Zeno require a buffer tank?

No, the manufacturer states that a buffer tank is not strictly required, though a volumiser may be necessary depending on the total system water volume. Installers should ensure the system meets the minimum water flow rate of 10 litres per minute and that the total volume is sufficient to prevent short-cycling.

What does fault code P01 mean on the Warmflow AS01-R32?

Heating Return Temperature Sensor Error Likely causes: The temperature sensor is faulty or disconnected.. Test the operation of the heating return temperature sensor and re-connect/replace if necessary.

What does fault code P02 mean on the Warmflow AS01-R32?

Heating Flow Temperature Sensor Error Likely causes: The temperature sensor is faulty or disconnected.. Test the operation of the heating flow temperature sensor and re-connect/replace if necessary.

What does fault code P03 mean on the Warmflow AS01-R32?

DHW Cylinder Temperature Sensor Error Likely causes: The temperature sensor is faulty or disconnected.. Test the operation of the DHW cylinder temperature sensor and re-connect/replace if necessary.

What does fault code P04 mean on the Warmflow AS01-R32?

Ambient Temperature Sensor Error Likely causes: The temperature sensor is faulty or disconnected.. Test the operation of the ambient temperature sensor and re-connect/replace if necessary.

What does fault code P17 mean on the Warmflow AS01-R32?

Suction Temperature Sensor Error Likely causes: The temperature sensor is faulty or disconnected.. Test the operation of the refrigerant suction line temperature sensor and re-connect/replace if necessary.

What does fault code P42 mean on the Warmflow AS01-R32?

Room Temperature Sensor Error Likely causes: The temperature sensor is faulty or disconnected.. Test the operation of the room temperature sensor (if fitted) and re-connect/replace if necessary.

What does fault code P101 mean on the Warmflow AS01-R32?

EVI Inlet Temperature Sensor Error Likely causes: The temperature sensor is faulty or disconnected.. Test the operation of the EVI inlet line temperature sensor and re-connect/replace if necessary.

What does fault code P102 mean on the Warmflow AS01-R32?

EVI Outlet Temperature Sensor Error Likely causes: The temperature sensor is faulty or disconnected.. Test the operation of the EVI out line temperature sensor and re-connect/replace if necessary.

What does fault code P153 mean on the Warmflow AS01-R32?

Evaporator Temperature Sensor Error Likely causes: The temperature sensor is faulty or disconnected.. Test the operation of the evap. temperature sensor and re-connect/replace if necessary.

What does fault code P181 mean on the Warmflow AS01-R32?

Discharge Temperature Sensor Error Likely causes: The temperature sensor is faulty or disconnected.. Test the operation of the refrigerant discharge line temperature sensor and re-connect/replace if necessary.

What does fault code P182 mean on the Warmflow AS01-R32?

Discharge Overheat Temperature Sensor Error Likely causes: The temperature sensor is faulty or disconnected.. Test the operation of the discharge line overheat temperature sensor and re-connect/replace if necessary.

What does fault code PP2 mean on the Warmflow AS01-R32?

Suction Pressure Sensor Error Likely causes: The pressure sensor is faulty or disconnected.. Test the operation of the suction line pressure sensor and re-connect/replace if necessary.

What does fault code TP mean on the Warmflow AS01-R32?

Low Ambient Temperature Warning Likely causes: The ambient temperature is too low.. Test the operation of the ambient temperature sensor and re-connect/replace if necessary.

What does fault code E003 mean on the Warmflow AS01-R32?

Driver Board Self Test Likely causes: There is a fault affecting the Fan Motor. Check the operation of the fan and check the connections.

What does fault code E04 mean on the Warmflow AS01-R32?

Electric Overheat Protection Likely causes: The compressor is overloaded.. Check the operation of the refrigeration circuit in terms of gas pressure and charge.

What does fault code E08 mean on the Warmflow AS01-R32?

Communication Error Likely causes: There is a communication error between the controller and the appliance.. Check the wiring and connections between the controller and the appliance.

What does fault code E11 mean on the Warmflow AS01-R32?

High Pressure Protection Likely causes: The high pressure switch in the refrigeration circuit has been tripped.. Check the operation of the high pressure switch and refrigeration circuit in terms of gas pressure.

What does fault code E12 mean on the Warmflow AS01-R32?

Low Pressure Protection Likely causes: The low pressure switch in the refrigeration circuit has been tripped.. Check the operation of the low pressure switch and refrigeration circuit in terms of gas pressure.

What does fault code E19 mean on the Warmflow AS01-R32?

Primary Anti-freezing Protection Likely causes: The ambient temperature is low.. Test the operation of the ambient temperature sensor and re-connect/replace if necessary.

What does fault code E29 mean on the Warmflow AS01-R32?

Secondary Anti-freezing Protection Likely causes: The ambient temperature is low.. Test the operation of the ambient temperature sensor and re-connect/replace if necessary.

Warmflow Zeno_R32_User_Manual — Specs & Fault Codes

Engineer's overview

The Warmflow Zeno_R32_User_Manual describes the Zeno A-Series, a monobloc air-source solution for UK heating engineers. The range consists of three models: the AS01-R32 (8kW), AS02-R32 (12kW), and the AS03-R32 (20kW). Each unit is a DC inverter-driven system designed for external installation, requiring no indoor refrigerant handling, which simplifies the installation process for F-gas certified technicians.

Performance characteristics focus on efficiency and noise control. The 8kW model achieves a COP of 4.58 at an ambient temperature of 7°C and a flow temperature of 35°C. Even at higher flow temperatures of 55°C, the unit maintains a COP of 2.68, supporting an ErP rating of A++. The system operates in conditions down to a minimum outdoor temperature of -25°C and provides a maximum flow temperature of 65°C, making it compatible with radiator circuits and underfloor heating.

Electrical requirements vary by model size. The AS01-R32 requires a 20A MCB, while the AS03-R32 requires a 40A MCB. All units operate on a 230V single-phase supply. Hydraulic connections utilize 1" or 1 1/4" female BSP connections depending on the output. A minimum water flow rate of 10 litres per minute is required for the 8kW unit to prevent low-flow errors.

The Zeno A-Series features an integrated touchscreen controller and is compatible with the Warmlink app via built-in WiFi. It supports weather compensation and Modbus communication for system integration. Maintenance is required every 12 months, involving ten specific steps including checking the heating circuit filter, glycol concentration via refractometer, and inhibitor levels.

For troubleshooting, the Zeno range utilizes a comprehensive fault code system. Common errors include E032 for low flow, which requires checking the plumbing circuit for blockages or air, and P01 through P182 for various temperature sensor failures. The units are MCS certified and eligible for the Boiler Upgrade Scheme (BUS), provided they are installed by an MCS-accredited engineer. Warmflow provides a 5-year standard warranty on parts and labour, subject to registration and annual servicing. The outdoor unit for the 8kW model measures 805mm in height and 1002mm in width, with a sound power level of 50 dB(LWA).

AS01-R32 fault codes

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/warmflow/as01-r32#fault-p01 to jump straight to the entry.

Complete list of fault codes for this Warmflow AS01-R32
Code	Meaning	Details
P01Lockout	Heating Return Temperature Sensor Error Show causes & actions Likely causes The temperature sensor is faulty or disconnected. Engineer action Test the operation of the heating return temperature sensor and re-connect/replace if necessary.	Details
P02Lockout	Heating Flow Temperature Sensor Error Show causes & actions Likely causes The temperature sensor is faulty or disconnected. Engineer action Test the operation of the heating flow temperature sensor and re-connect/replace if necessary.	Details
P03Lockout	DHW Cylinder Temperature Sensor Error Show causes & actions Likely causes The temperature sensor is faulty or disconnected. Engineer action Test the operation of the DHW cylinder temperature sensor and re-connect/replace if necessary.	Details
P04Lockout	Ambient Temperature Sensor Error Show causes & actions Likely causes The temperature sensor is faulty or disconnected. Engineer action Test the operation of the ambient temperature sensor and re-connect/replace if necessary.	Details
P17Lockout	Suction Temperature Sensor Error Show causes & actions Likely causes The temperature sensor is faulty or disconnected. Engineer action Test the operation of the refrigerant suction line temperature sensor and re-connect/replace if necessary.	Details
P42Lockout	Room Temperature Sensor Error Show causes & actions Likely causes The temperature sensor is faulty or disconnected. Engineer action Test the operation of the room temperature sensor (if fitted) and re-connect/replace if necessary.	Details
P101Lockout	EVI Inlet Temperature Sensor Error Show causes & actions Likely causes The temperature sensor is faulty or disconnected. Engineer action Test the operation of the EVI inlet line temperature sensor and re-connect/replace if necessary.	Details
P102Lockout	EVI Outlet Temperature Sensor Error Show causes & actions Likely causes The temperature sensor is faulty or disconnected. Engineer action Test the operation of the EVI out line temperature sensor and re-connect/replace if necessary.	Details
P153Lockout	Evaporator Temperature Sensor Error Show causes & actions Likely causes The temperature sensor is faulty or disconnected. Engineer action Test the operation of the evap. temperature sensor and re-connect/replace if necessary.	Details
P181Lockout	Discharge Temperature Sensor Error Show causes & actions Likely causes The temperature sensor is faulty or disconnected. Engineer action Test the operation of the refrigerant discharge line temperature sensor and re-connect/replace if necessary.	Details
P182Lockout	Discharge Overheat Temperature Sensor Error Show causes & actions Likely causes The temperature sensor is faulty or disconnected. Engineer action Test the operation of the discharge line overheat temperature sensor and re-connect/replace if necessary.	Details
PP2Lockout	Suction Pressure Sensor Error Show causes & actions Likely causes The pressure sensor is faulty or disconnected. Engineer action Test the operation of the suction line pressure sensor and re-connect/replace if necessary.	Details
TPLockout	Low Ambient Temperature Warning Show causes & actions Likely causes The ambient temperature is too low. Engineer action Test the operation of the ambient temperature sensor and re-connect/replace if necessary.	Details
E003Lockout	Driver Board Self Test Show causes & actions Likely causes There is a fault affecting the Fan Motor Engineer action Check the operation of the fan and check the connections.	Details
E04Lockout	Electric Overheat Protection Show causes & actions Likely causes The compressor is overloaded. Engineer action Check the operation of the refrigeration circuit in terms of gas pressure and charge.	Details
E08Lockout	Communication Error Show causes & actions Likely causes There is a communication error between the controller and the appliance. Engineer action Check the wiring and connections between the controller and the appliance.	Details
E11Lockout	High Pressure Protection Show causes & actions Likely causes The high pressure switch in the refrigeration circuit has been tripped. Engineer action Check the operation of the high pressure switch and refrigeration circuit in terms of gas pressure.	Details
E12Lockout	Low Pressure Protection Show causes & actions Likely causes The low pressure switch in the refrigeration circuit has been tripped. Engineer action Check the operation of the low pressure switch and refrigeration circuit in terms of gas pressure.	Details
E19Lockout	Primary Anti-freezing Protection Show causes & actions Likely causes The ambient temperature is low. Engineer action Test the operation of the ambient temperature sensor and re-connect/replace if necessary.	Details
E29Lockout	Secondary Anti-freezing Protection Show causes & actions Likely causes The ambient temperature is low. Engineer action Test the operation of the ambient temperature sensor and re-connect/replace if necessary.	Details
E032Lockout	Low Flow Error Show causes & actions Likely causes There is not enough flow in the heating circuit. Engineer action Check the plumbing circuit for blockages or air, valves are open and the operation of the circulating pump.	Details
E051Lockout	Compressor Overload Show causes & actions Likely causes The compressor is overloaded. Engineer action Check the operation of the refrigeration circuit in terms of gas pressure and charge.	Details
E065Lockout	Outlet Water Temp. Overtemp. Show causes & actions Likely causes The temperature of the outlet water is too high. Engineer action Check there is enough water in the system and there are no air locks/lack of flow.	Details
E071Lockout	Outlet Water Temp. Lowtemp. Show causes & actions Likely causes The temperature of the outlet water is too low. Engineer action Check there is enough water in the system and there are no air locks/lack of flow.	Details
E081Lockout	DC Fan Motor Communication Error Show causes & actions Likely causes There is a communication error between the fan speed control module and the main board. Engineer action Check the wiring and connection between the fan speed control module and the main board.	Details
E082Lockout	DC Fan Motor 2 Communication Error Show causes & actions Likely causes There is a communication error between the fan speed control module and the main board. Engineer action Check the wiring and connection between the fan speed control module and the main board.	Details
E084Lockout	Display and Main Controller Not Compatible Show causes & actions Likely causes The software on the Display is not compatible with the main control board. Engineer action Replace the Display with a compatible version.	Details
E101Lockout	Compressor Overcurrent Show causes & actions Likely causes The compressor is overloaded. Engineer action Check the operation of the refrigeration circuit in terms of gas pressure and charge.	Details
E103Lockout	Fan Motor 1 Overload Show causes & actions Likely causes The Fan Motor 1 is overloaded. Engineer action Check the operation of the fan.	Details
E203Lockout	Fan Motor 2 Overload Show causes & actions Likely causes The Fan Motor 2 is overloaded. Engineer action Check the operation of the fan.	Details
E171Lockout	Anti-freezing Protection Show causes & actions Likely causes There is not enough flow in the heating circuit. Engineer action Check the plumbing circuit, valves and operation of the circulating pump.	Details
F00Lockout	Inverter IPM Overcurrent Shutdown Show causes & actions Likely causes Inverter IPM input current is too high. Engineer action Check the current measurement and adjust/replace if necessary.	Details
F01Lockout	Compressor Start-up Failure Show causes & actions Likely causes Voltage too low. Damage to inverter. Engineer action Check the voltage measurement. Check the inverter for damage.	Details
F03Lockout	Power Factor Correction (PFC) Error Show causes & actions Likely causes There is an error with the power factor correction circuit. Engineer action Check the power correction wiring for a break or short circuit.	Details
F05Lockout	DC Bus Overload Show causes & actions Likely causes The DC bus voltage is higher than the overload protection limit. Engineer action Check the input voltage measurement.	Details
F06Lockout	DC Bus Underload Show causes & actions Likely causes The DC bus voltage is lower than the underload protection limit. Engineer action Check the input voltage measurement.	Details
F07Lockout	AC Input Underload Show causes & actions Likely causes The AC input voltage is low causing the input current to be low. Engineer action Check the input voltage measurement.	Details
F08Lockout	AC Input Overload Show causes & actions Likely causes The AC input voltage is high causing the input current to be high. Engineer action Check the input voltage measurement.	Details
F09Lockout	Input Voltage Read Error Show causes & actions Likely causes The input voltage reading is incorrect/out of range. Engineer action Check the input voltage measurement.	Details
F10Lockout	DSP and PFC Communication Error Show causes & actions Likely causes There is a communication error between the DSP and the PFC. Engineer action Check the wiring and connection between the DSP and the PFC.	Details
F11Lockout	DSP Communication Error Show causes & actions Likely causes There is a communication error between the DSP and the inverter. Engineer action Check the wiring and connection between the DSP and the inverter.	Details
F12Lockout	Inverter Communication Error Show causes & actions Likely causes There is a communication error between the inverter and the main board. Engineer action Check the wiring and connection between the inverter and the main board.	Details
F13Lockout	IPM Over Temperature Protection Show causes & actions Likely causes There IPM module temperature is too high. Engineer action Check the current measurement and adjust/replace if necessary.	Details
F15Lockout	Input Voltage Lacking Phase Show causes & actions Likely causes The input voltage has lost a phase. Engineer action Check the input voltage measurement.	Details
F16Lockout	Weak Magnetism Error Show causes & actions Likely causes The magnetic force of the compressor motor is too low. Engineer action Check the operation of the refrigeration circuit in terms of gas pressure and charge.	Details
F17Lockout	Module/Radiator Sensor Error Show causes & actions Likely causes A transducer has overheated. Engineer action Check the current measurement.	Details
F18Lockout	IPM Current Read Error Show causes & actions Likely causes The IPM current reading is incorrect/out of range. Engineer action Check the IPM current measurement.	Details
F20Lockout	IGBT Power Device Error Show causes & actions Likely causes A transducer has overheated. Engineer action Check the current measurement.	Details
F21Lockout	Overload Error Show causes & actions Likely causes The compressor input current is too high. Engineer action Check the operation of the refrigeration circuit in terms of gas pressure and charge.	Details
F22Lockout	AC Input Over Current Error Show causes & actions Likely causes The AC input current is too high. Engineer action Check the current measurement and adjust/replace if necessary.	Details
F23Lockout	EEPROM Alarm Show causes & actions Likely causes MCU Error Engineer action Replace board.	Details
F24Lockout	EEPROM Alarm Show causes & actions Likely causes MCU Error Engineer action Replace board.	Details
F25Lockout	LP 15V Error Show causes & actions Likely causes THE V15V is out of range. Engineer action Check the V15V input voltage is between 12.5V and 16.5V.	Details
F26Lockout	IGBT Power Device Over Temperature Show causes & actions Likely causes The IGBT transducer temperature is too high. Engineer action Check the current measurement and adjust/replace if necessary.	Details
F031Lockout	DC Fan Motor 1 Error Show causes & actions Likely causes There is no connection between the fan module and motor. The fan motor is in locked rotor state. Engineer action Check the connection between the fan module and motor. Replace the fan motor.	Details
F032Lockout	DC Fan Motor 2 Error (AS03 models only) Show causes & actions Likely causes There is no connection between the fan module and motor. The fan motor is in locked rotor state. Engineer action Check the connection between the fan module and motor. Replace the fan motor.	Details
F33Lockout	Compressor Current Frequency Reductiond Error Show causes & actions Likely causes The Compressor current reading is incorrect/out of range. Engineer action Check the Compressor current measurement.	Details

Common AS01-R32 problems & troubleshooting

Patterns that group across the manufacturer's fault-code table. Each entry links to the full code listing further down the page.

How to fix the AS01-R32 heating return temperature sensor errorLockout

Engineer: Test the operation of the heating return temperature sensor and re-connect/replace if necessary.

Triggered by fault code P01.

How to fix the AS01-R32 heating flow temperature sensor errorLockout

Engineer: Test the operation of the heating flow temperature sensor and re-connect/replace if necessary.

Triggered by fault code P02.

How to fix the AS01-R32 dhw cylinder temperature sensor errorLockout

Engineer: Test the operation of the DHW cylinder temperature sensor and re-connect/replace if necessary.

Triggered by fault code P03.

AS01-R32

AS01-R32 at a glance

AS01-R32

AS01-R32 at a glance

Register this Warmflow AS01-R32 on BoilerTag

AS01-R32 data sheet

Engineer's overview

AS01-R32 fault codes

Common AS01-R32 problems & troubleshooting

How to fix the AS01-R32 heating return temperature sensor errorLockout

How to fix the AS01-R32 heating flow temperature sensor errorLockout

How to fix the AS01-R32 dhw cylinder temperature sensor errorLockout

How to fix the AS01-R32 ambient temperature sensor error

AS01-R32 FAQs

Every boiler brochure, free with BoilerTag

Working on a Warmflow AS01-R32?

How to fix the AS01-R32 suction temperature sensor errorLockout

Likely causes that trigger multiple AS01-R32 fault codes

AS01-R32 at a glance

AS01-R32 at a glance

Register this Warmflow AS01-R32 on BoilerTag

AS01-R32 data sheet

Engineer's overview

AS01-R32 fault codes

Common AS01-R32 problems & troubleshooting

How to fix the AS01-R32 heating return temperature sensor errorLockout

How to fix the AS01-R32 heating flow temperature sensor errorLockout

How to fix the AS01-R32 dhw cylinder temperature sensor errorLockout

How to fix the AS01-R32 ambient temperature sensor error

AS01-R32 FAQs

Is the Warmflow Zeno A-Series eligible for the Boiler Upgrade Scheme (BUS)?

What does fault code E032 mean on a Warmflow Zeno heat pump?

What is the maximum flow temperature of the Warmflow Zeno R32?

What are the electrical requirements for the Warmflow AS01-R32?

How often should a Warmflow Zeno heat pump be serviced?

What is the sound level of the Warmflow Zeno A-Series?

Does the Warmflow Zeno require a buffer tank?

Every boiler brochure, free with BoilerTag

Other Warmflow heat pumps

Working on a Warmflow AS01-R32?

How to fix the AS01-R32 suction temperature sensor errorLockout

Likely causes that trigger multiple AS01-R32 fault codes