Climaveneta W3000 Alarm Codes Explained

How to View and Reset W3000 Alarms

Press the ALARM key once to open the alarms menu and see the message and code. If more than one alarm is present, scroll with the up and down keys. On a W3000 base, “NO A” means there are no active alarms.

To reset, press and hold the ALARM key until “No Alarm Active” (or “No A”) appears. If that message does not appear, one or more alarm conditions are still present, and the machine is telling you the fault has not cleared.

The manufacturer classifies each alarm by reset type, and it is worth knowing which you are dealing with:

• A, automatic: clears itself when the condition goes away.
• M, manual: needs a deliberate reset, because the controller has decided it should not restart on its own.
• S, signal: a warning only, such as a maintenance hours reminder. The unit keeps running.
• A/M, mixed: resets automatically a set number of times, then goes to manual if it keeps happening.

A manual-reset alarm is a deliberate design choice by Climaveneta. If you find yourself resetting the same manual alarm repeatedly, the machine is protecting itself from something that has not been fixed.

Unit and Water-Side Alarms (000 to 099)

Code	Meaning	What usually causes it	Who can deal with it
002	Phase sequence or voltage out of range	Incorrect phase connection or a supply problem. Shuts the whole unit down. Common after electrical work or a supply fault.	Site electrician or engineer
003	Evaporator flow switch	No flow through the evaporator: blocked strainer, failed or airlocked pump, closed valve, or a faulty flow switch. Resets itself up to three times in an hour if flow returns, then goes manual.	Site team can check pump, valves and strainer
005	Low inlet temperature (heat pump mode)	Water returning colder than expected in heat pump operation.	Engineer needed
006	High inlet temperature (chiller mode)	Return water hotter than the unit expects: process load above design, a hot fill after shutdown, or insufficient capacity.	Site team can check load, engineer if it persists
010	Evaporator antifreeze	Water leaving the evaporator too cold. Usually low flow, weak or missing glycol, or a probe reading wrongly. Manual reset by design. See our glycol concentration guide.	Site team can check flow and glycol, engineer if unclear
014	Insufficient system pressure	External pressure switch has stopped the unit. Often a water leak or loss of system pressure.	Site team can check system pressure and top up
017	Low external air temperature	Ambient below the setpoint. A signal rather than a fault, but relevant in winter.	No action, note for winter operation
021	Low water charge	Evaporator inlet temperature changing too quickly, suggesting a low water level in the system.	Site team can check system volume and pressure
022	Low water flow	Temperature difference across the evaporator too high, meaning flow is below what the unit needs. Manual reset.	Site team can check pump and strainers, engineer if unclear
045	Condenser flow switch	As 003, on the condenser side of a water-cooled or reversible unit.	Site team can check pump, valves and strainer
046	Recuperator flow switch	No flow through the heat recovery circuit.	Site team can check, engineer if unclear
051 / 052	Pump 1 and pump 2 maintenance	Running hours threshold reached. A reminder, not a fault.	Raise at next service
075	Condenser antifreeze	Water leaving the condenser too cold on a water-cooled or reversible unit. Manual reset.	Engineer needed
076	Recuperator antifreeze	Low water temperature leaving the heat recovery circuit.	Engineer needed
081 / 082	Pump 1 and pump 2 thermal switch	Pump motor has overheated: seized or stiff pump, electrical fault, or an overload set too tight. Manual reset.	Engineer needed
085	Condenser pump thermal switch	Condenser pump overheated.	Engineer needed
087	Glycol pump thermal switch	Glycol pump overheated on a free cooling unit.	Engineer needed
090 to 105	Slave card or expansion module no-link	A control board or expansion module has lost communication. Cable, connector or board fault, sometimes after a power event.	Engineer needed

Compressor Alarms (100s)

The last digit is the compressor number, so 111 is compressor 1 and 112 is compressor 2.

Code	Meaning	What usually causes it	Who can deal with it
111 to 114	Compressor oil alarm	Low oil level or oil pressure. Poor oil return, refrigerant migration, low charge or a failing oil pump. Manual reset, and rightly so: this is how compressors are lost.	F-Gas engineer needed, stop the machine
121 to 124	High outlet (discharge) temperature	Discharge temperature above the limit: low charge, high compression ratio, failing valves or expansion problems. Manual reset.	F-Gas engineer needed
131 to 136	Compressor fault	Motor overheated or another compressor protection has tripped. Electrical fault, high load, low voltage or a failing compressor.	Engineer needed
141 to 144	Compressor offline	No communication with the compressor, on units with centrifugal compressors.	Engineer needed
151 to 156	Compressor maintenance	Running hours threshold reached. A reminder rather than a fault.	Raise at next service
181 to 186	Compressor start-up limit	Too many starts in an hour. Often points to an oversized machine for the current load, or a control or setpoint problem.	Engineer needed

Circuit Alarms (200s)

The last digit is the circuit number: 211 is circuit 1, 212 is circuit 2.

Code	Meaning	What usually causes it	Who can deal with it
211 to 214	Circuit high pressure	Dirty or blocked condenser coil, failed condenser fan, high ambient, restricted airflow, or on water-cooled units a loss of condenser water. Manual reset: do not keep clearing it.	Site team can check coil and fans, engineer for the rest
221 to 224	Circuit fan thermal protection	A condenser fan has overheated and stopped: seized bearing, damaged blade, debris or an electrical fault.	Engineer needed
231 to 234	Circuit low pressure	Detected by the transducer or pressure switch. Usually refrigerant loss, but also expansion valve or solenoid faults, a blocked drier, icing or low flow.	F-Gas engineer needed
241 to 244	Transducer high pressure	High pressure detected by the transducer before the safety switch trips. Same causes as 211.	Site team can check coil and fans, engineer for the rest
251 to 254	Circuit start-up timeout	The circuit tried to start and pressure did not build. Often the first sign that refrigerant has been lost.	F-Gas engineer needed
261 to 264	No refrigerant in circuit	Follows at least eight hours of start-up timeouts. The controller is telling you the circuit has lost its charge, which means a leak. Under F-Gas rules the leak must be found and repaired, not simply topped up. See our F-Gas compliance guide.	F-Gas engineer needed
271 to 274	Finned coil obstructed	Condenser coil blocked with dirt, leaves, cardboard dust or production debris. One of the most preventable alarms on the list.	Site team can inspect, engineer to clean properly
281 to 284	Insufficient evaporation pressure	Evaporating pressure below setpoint, which again often means refrigerant loss. Manual reset.	F-Gas engineer needed
291 to 294	Insufficient refrigerant in circuit	The unit has been running below the expected approach temperature, suggesting the charge is low.	F-Gas engineer needed

Inverter and Centrifugal Compressor Alarms (300s)

These apply to units with inverter-driven or centrifugal compressors, and cover inverter temperature (301 to 304), discharge temperature (311 to 314), compressor low and high pressure (321 to 324 and 331 to 334), input current (341 to 344), rotor temperature (351 to 354), compression ratio (361 to 364), bearings (371 to 374), SCR temperature (381 to 384) and rotor block (391 to 394).

All of these need an engineer. On centrifugal machines in particular, bearing and rotor alarms should stop the machine until it has been investigated.

Probe Alarms (400s)

The 400 series covers probe faults, where the controller cannot trust the value a sensor is reporting. A failed or disconnected probe often causes odd behaviour elsewhere, such as unstable temperatures or nuisance alarms, so it is worth fixing promptly even though the unit may keep running.

Which W3000 Alarms Are Safe to Reset?

• Usually safe to reset once you have checked the obvious: 003 and 045 flow switches, 014 system pressure, 021 low water charge, and maintenance warnings.
• Reset once, then stop: 010 and 075 antifreeze, 211 high pressure, 231 low pressure, 022 low water flow.
• Do not simply reset: 111 to 114 oil, 121 to 124 high discharge temperature, 131 to 136 compressor faults, and any of the 300 series.
• Stop and call someone: 261 no refrigerant and 291 insufficient refrigerant. Running a machine that has lost its charge risks the compressor, and the leak is a legal obligation under the F-Gas Regulations.

Codes and behaviour vary between W3000 software versions and machine configurations, so treat this as a guide alongside the manual for your specific unit. If you are unsure which version you have, the display or the unit documentation will tell you, or we can identify it from a photo.