Why is my Vaillant VAI 6-035 WN not cooling enough?
- JJay LangAug 12, 2025
Several factors can cause insufficient cooling or heating. Ensure that all doors and windows are closed. Remove any nearby heat sources. Check that the thermostat is set correctly for cooling or heating mode. Clear any obstacles blocking the air inlet or outlet. The unit may need a few moments to reach the set temperature. Clean a dirty or blocked air filter, as it should be cleaned every 15 days. Use a curtain to block direct sunlight during cooling.