Inventum fault code AP-4 (geen fault)
Fault code AP-4 (geen fault) on an Inventum heat pump (including Ecolution) means: Ventilation heat pump in operation for the 2nd time within 15 minutes. Reset the appliance once. If the code comes back, a part is usually faulty. You can check the water pressure and settings yourself; leave work on gas-carrying parts to a certified gas engineer.
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 AP-4 (geen fault) on an Inventum heat pump indicates: Ventilation heat pump in operation for the 2nd time within 15 minutes.
Fixing fault code AP-4 (geen fault): step by step
- Read the water pressure on the display or gauge. With the system cold it should be between 1.5 and 2 bar.
- Bleed the radiators with a radiator key, then check the pressure again and top up if needed.
- When there is a heat demand, feel or listen whether the pump is running (a light vibration or hum).
- Reset the appliance once. If the code comes straight back, do not keep resetting it.
- If the pump is not running, or the code comes back, the pump is seized or faulty.
Applies to
Inventum Ecolution, Combi 50, Solo.
Fault code AP-4 (geen fault) on other Inventum series
The same code does not mean the same thing on every series. Check the rating plate to see which series you have:
- AP4 (geen fault) on Ecolution, Modul-AIR: Pause mode. The compressor may not be started yet.
- AP4 (geen fault) on Spaarpomp, Niet van toepassing: Pause mode, compressor may not be started.
Matching parts
Inventum parts are available from Instalpunt; shipping to EU countries from €12.95 (€16.95 for more distant countries), usually 3–5 working days.
This message does not point directly to one faulty part. These are the parts that most often fit this appliance:
- Inventum ring gasket 138x105x1.5 € 21.43
- Inventum fan plate Optima DC for service AC version € 1,896.51
- Inventum thermostat heat pump water heater € 53.85
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 Inventum heat pump fault code AP-4 (geen fault) mean?
Ventilation heat pump in operation for the 2nd time within 15 minutes.
How do I fix fault code AP-4 (geen fault) on an Inventum 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 Inventum fault code AP-4 (geen fault)?
That depends on the exact cause. In the Inventum parts overview at Instalpunt you will find the current price and stock for each part.
Can I fix fault code AP-4 (geen fault) 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 Inventum heat pump faults and codes at a glance →