What does Error Code E2 mean on a Voltas AC?

Error Code E2 on a Voltas Air Conditioner indicates a 'Indoor Coil Temperature Sensor Fault'. This copper-tipped sensor monitors the temperature of the refrigerant pipes to prevent freezing.

How is E2 different from E1?

E1 is the 'Room Sensor' (Plastic tip) that measures air temperature. E2 is the 'Coil Sensor' (Copper tip) that measures pipe temperature. Both are usually plugged into the PCB but perform different safety functions.

Common causes include the sensor slipping out of its copper holder, the wire being bitten by rats, or the sensor's resistance value drifting due to age and moisture.

Voltas AC Error Code E2 | Coil Sensor Error | Atlas Aircon

Coil Sensor Fault

Voltas Error E2

Indoor Coil Sensor Failure.
Your Anti-Freeze Protection is down.

Part

Copper Sensor

Common Cause

Rat Bite / Cut

Action

Replace Sensor

The “Copper Tip” Problem

The E2 Error points to the Indoor Coil Sensor. Unlike the black plastic E1 sensor that hangs in the air, the E2 sensor has a copper tip and is inserted directly into a small brass holder welded onto the cooling pipes.

Why it’s critical: This sensor tells the PCB if the pipes are getting too cold (reaching 0°C). Without it, the AC can turn into a block of ice, potentially cracking the pipes or damaging the compressor.

1 DIY Checks (Before Calling Us)

Check Placement

Open the grill. Look for the wire leading to the copper coils on the right. Has the sensor slipped out of its metal holder? If it’s dangling in the air, it will trigger E2.

Rat Damage

Just like E1, rats love to chew the wires of the coil sensor. If you see exposed copper wire, that’s your problem.

Intermittent E2?

Does E2 only appear after running for 10 minutes? This often means the sensor is working but is “drifting” (giving wrong values) as it gets cold.

Atlas Aircon Repair Protocol

How we fix the E2 Fault:

01.
Resistance Measurement We unplug the sensor and check its Ohms with a multimeter. A healthy Voltas coil sensor typically reads 5kΩ to 10kΩ at 25°C.
02.
Replacement (Recommended) Copper sensors degrade due to constant heating and cooling. Even if the wire isn’t cut, we recommend replacing the sensor for long-term reliability.
03.
Thermal Paste Application For accurate reading, we often apply a tiny bit of thermal paste before inserting the new sensor into the copper sleeve.

Estimated Repair Cost (Atlas Aircon)

Re-fixing (Loose): ₹350 – ₹450

New Copper Sensor: ₹750 – ₹1,100

Frequently Asked Questions

Can I swap the E1 and E2 sensors?

Never. Although they might look similar or have the same plug, the E2 sensor is specifically encased in copper to respond faster to pipe temperature changes. The plastic E1 sensor cannot handle the direct contact with freezing pipes.

Does E2 mean my AC gas is low?

Usually, E2 is an electrical fault (the sensor itself). However, if the sensor is working correctly, it might trigger E2 if the gas is extremely low and causing the coil to freeze abnormally fast, but EC is the standard code for low gas. E2 is almost always the sensor.

Where is the E2 sensor located?

Open the front panel and remove the filters. On the right-hand side of the cooling fins (evaporator), you will see a small copper pocket welded to the U-bend of the pipe. The sensor is inserted there.

ATLAS AIRCON

Voltas AC Error E2