E4
Voltas Split AC
Severity: ModerateWhat Does This Error Mean?
E4 on a Voltas AC means the indoor evaporator coil thermistor has detected an abnormally low temperature — the coil is getting too cold and is at risk of freezing. Voltas stops the compressor temporarily to allow the coil to warm up. A blocked air filter is the most common reason.
Affected Models
- Voltas 1.5 Ton Inverter Split AC
- Voltas 1 Ton Inverter Split AC
- Voltas 2 Ton Inverter Split AC
- Voltas Adjustable Inverter Series
- Voltas Vertis Plus Series
Common Causes
- Indoor air filter dirty or blocked — restricted airflow cools the coil excessively
- Low refrigerant — reduced refrigerant pressure causes the evaporator to run too cold
- Indoor blower motor running slowly or not at full speed
- Temperature set too low in a small, well-insulated room
- Indoor coil thermistor sensor fault — reporting incorrect low temperature
How to Fix It
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Switch the AC to fan mode and clean the air filter.
Fan mode runs the blower without cooling, which melts any ice forming on the coil. While the fan runs, remove and wash the air filter under running water. Allow the filter to dry completely before reinserting.
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Raise the set temperature above 24 degrees C.
Very low set temperatures in a small or well-insulated room can cause E4 even with a clean filter. Voltas recommends 24-26 degrees C as the optimal range for efficiency and comfort.
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Restart in cooling mode after 30-60 minutes.
Once the filter is clean and the coil has defrosted, restart in cooling mode. If E4 returns within an hour, call a Voltas technician.
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Call Voltas service if E4 recurs despite a clean filter.
Low refrigerant or a blower motor issue requires professional diagnosis. Voltas customer care: 1800-209-1618.
Frequently Asked Questions
How do I know if the Voltas AC coil has iced up?
Look at the indoor unit — if ice has formed on the evaporator, you may see frost on the unit casing or water dripping more than usual. You can also feel for unusually cold air coming from the vents when the AC should be off (ice melting). In severe cases, ice can be seen through the louvres.