Alde Furnace: “Overheat PCB”
danger RV furnace fault codes
What it means
The boiler's circuit board (PCB) failsafe over-temperature protection has triggered, typically because the boiler compartment is too hot or the heating fluid is low.
Most likely causes
- Boiler compartment poorly ventilated or vents obstructed most likely
- Stowage placed in the boiler compartment blocking airflow common
- Low fluid level in the expansion tank common
Safe checks you can do yourself
- Check the fluid level in the expansion tank: about 1 cm above the Min mark when cool
- Make sure the boiler compartment is ventilated and the vents are not blocked
- Remove any items stored in the boiler compartment that could trap heat
How to reset / clear Overheat PCB
- Clear the compartment, restore ventilation and correct fluid level; allow the boiler to cool
- Reset: disconnect the panel from the boiler, remove 230V, and disconnect 12V from the boiler
- Reconnect power and restart
When to call a technician
If ventilation is clear and fluid level is correct but the Overheat PCB fault persists, contact an Alde dealer.
Applies to
Alde Compact 3020 HE
FAQ
What does Alde Furnace code "Overheat PCB" mean?
The boiler's circuit board (PCB) failsafe over-temperature protection has triggered, typically because the boiler compartment is too hot or the heating fluid is low.
How do I reset Alde Furnace Overheat PCB?
Clear the compartment, restore ventilation and correct fluid level; allow the boiler to cool Reset: disconnect the panel from the boiler, remove 230V, and disconnect 12V from the boiler Reconnect power and restart
What is the most common cause of Overheat PCB on a Alde Furnace?
The most likely cause is boiler compartment poorly ventilated or vents obstructed.
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Sources
- Operating Instructions – Alde Compact 3020 HE — Section 9:1 Error Messages – Overheat PCB (Alde International)
Note: Wording compiled from the operating instructions; phrasing of the on-screen message may vary slightly by firmware/panel version.
● Last verified 2026-06-29 · compiled from manufacturer documentation. Codes can vary by model year — always cross-check your unit’s manual.