Ariston Oven Error Code ER77

ER77 indicates a Key4 fault on the Ariston oven's touch control panel, meaning the fourth touch button zone is reporting a malfunction. The control board is detecting an unexpected or continuous signal from that input. This is most often caused by condensation on the panel surface or a problem with the components behind the touch interface. In some cases the display board itself has failed and needs to be replaced.

ER77 is a control panel input fault, not a heating or gas system fault, but continued use is not recommended while the error is active. A malfunctioning touch key could potentially send unintended commands to the oven's control system. It is best to resolve the fault before resuming normal cooking operations.

If the fault is caused by condensation, there is no parts cost involved. If the display board requires replacement, parts and labor costs typically range from around $150 to $350 depending on the specific model and local labor rates. Getting a diagnostic visit from a qualified technician will give you a more precise estimate for your unit.

The first step is something any homeowner can try: open the oven door and let the unit sit until any condensation on or behind the touch panel has fully dried, then check if the error clears. If the code returns, the next steps involve inspecting the inductive rubber pieces behind the panel and potentially replacing the display board, which are tasks better suited to a technician with experience opening appliance control panels.

A power reset by switching the oven off at the circuit breaker for a few minutes may temporarily clear the code, but if the underlying cause such as moisture or a faulty board is still present, the error will return. Drying out the panel after a reset gives the best chance of the fault not returning if condensation was the cause.