Vaillant fault code F.539
Fault code F.539 on a Vaillant heat pump (including aroTHERM Monoblock) means: Amount of refrigerant too low, air flow too low, no defrosting, resistance heater in the condensate tray defective, four-way valve defective, motor of the electronic expansion valve defective or connection defective. Reset the appliance once. If the code comes back, a part is usually faulty, often the siphon.
After a safety alert (gas, flue gas, combustion), reset no more than once and call in a certified gas engineer. If you smell gas, call your national gas emergency number or 112 immediately.
Cause
Fault code F.539 on a Vaillant heat pump indicates: Amount of refrigerant too low, air flow too low, no defrosting, resistance heater in the condensate tray defective, four-way valve defective, motor of the electronic expansion valve defective or connection defective.
Applies to
Vaillant aroTHERM Monoblock, VWL 115/2 A 400 V, VWL 155/2 A 400V, VWL 55/2 A 230V, VWL 55/3 A 230 V, VWL 85/2 A 230 V, VWL 85/3 A 230 V.
Matching parts
Vaillant parts are available from Instalpunt; shipping to EU countries from €12.95 (€16.95 for more distant countries), usually 3–5 working days.
Parts by Vaillant series: ecoTEC plus · ecoTEC pro.
Based on the cause, these original Vaillant parts fit (always check the type number of your appliance):
- Vaillant condenser damper € 8.50
- Vaillant capacitor for aroTHERM VWL 155/2 A 400V 0020175826 € 218.24
- Vaillant condenser 5kW € 537.09
Further reading on this cause
Other Vaillant codes with the same cause
- F.532 — Isolating valve was not opened, emitter circuit pump defective, all consumers in the…
- F.731 — Refrigerant pressure too high. The integrated high pressure switch (also replace filter)…
Fix it yourself or call an engineer?
Always consult the manual for your appliance and work safely. If in doubt or if the fault comes back, call in a qualified professional. A question about a part? Write to us at info@instalpunt.nl.
Frequently asked questions
What does Vaillant heat pump fault code F.539 mean?
Amount of refrigerant too low, air flow too low, no defrosting, resistance heater in the condensate tray defective, four-way valve defective, motor of the electronic expansion valve defective or connection defective.
How do I fix fault code F.539 on a Vaillant heat pump?
First check the cause described above. Then restart the appliance using the reset button. If the message comes back, a part usually needs replacing or the fault needs to be repaired by a qualified professional.
Which parts do I need for Vaillant fault code F.539?
That depends on the exact cause. In the Vaillant parts overview at Instalpunt you will find the current price and stock for each part.
Can I fix fault code F.539 myself?
You can reset the appliance and check things like the water pressure or settings yourself. Work on gas-carrying parts must be left to a certified gas engineer.
All Vaillant heat pump faults and codes at a glance →