Vaillant heating & air conditioning symbols chart

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1. Burner anti-cyclingBurner anti-cycling time
2. Burner onBurner operating
3. Domestic hot waterDomestic hot water active
4. FaultBoiler fault
5. Heating modeHeating mode active
6. Heating system filling pressureHeating filling pressure
7. Maintenance requiredThe boiler needs maintenance work but is not in fault and keeps running normally.
8. Summer modeSummer mode (heating off)