Voltas AC IoT Remote Control

ESPHome custom climate component for Voltas Inverter Split AC using the RG52E1/BGEF IR remote. Controls your Voltas AC from Home Assistant via an ESP32 with an IR LED — no cloud, fully local.

Works with Voltas split ACs that use the RG52E1/BGEF remote. May also work with other Voltas models using the same remote protocol.

Features

• 🌡️ Temperature Control: 17–30°C with 1° steps
• ❄️ Modes: Cool, Heat, Dry, Fan Only, Auto
• 💨 Fan Speed: Auto, Low, Medium, High
• 🔄 Swing: Vertical On/Off
• 💡 LED Display: On/Off toggle
• 📡 Dynamic Protocol: IR signals generated on-the-fly — all parameters (temp, mode, fan) are sent together in every command, so changing one never resets another
• 🏠 Fully Local: No cloud dependencies, works entirely on your LAN

Project Structure

voltas/
├── README.md
├── .gitignore
├── ACvoltas.txt                        # Captured raw IR signals (reference)
├── voltas.ino                          # Arduino Uno test sketch
└── esphome/
    ├── voltas_ac.yaml                  # ESPHome configuration
    ├── secrets.yaml.example            # Template for credentials
    └── custom_components/
        └── voltas_ac/
            ├── __init__.py             # Component registration
            ├── climate.py              # Climate platform definition
            └── voltas_ac.h             # Dynamic IR signal generator

Hardware

Components

Part	Purpose
ESP32 DevKit	Main controller
IR LED (940nm)	Transmits IR signals
PN2222A / 2N2222 NPN transistor	Drives IR LED for range
1.5kΩ resistor	Base current limiter

Wiring

                        3.3V
                          │
                    IR LED (+)
                          │
                    IR LED (-)
                          │
                    Collector (C)
                          │
ESP32 GPIO4 ──[1.5kΩ]── Base (B)     ← PN2222A
                          │
                    Emitter (E)
                          │
                         GND

PN2222A Pinout (flat side facing you)

 E  B  C

ESPHome Setup

1. Copy files to ESPHome config directory

config/
├── voltas-ac.yaml
└── custom_components/
    └── voltas_ac/
        ├── __init__.py
        ├── climate.py
        └── voltas_ac.h

2. Configure secrets

Copy the template and fill in your credentials:

cp secrets.yaml.example secrets.yaml

Edit secrets.yaml:

wifi_ssid: "YourWiFiName"
wifi_password: "YourWiFiPassword"
api_key: "your-base64-api-key"
ota_password: "your-ota-password"
ap_password: "fallback-hotspot-password"

Note: secrets.yaml is gitignored and must never be committed.

3. Flash

esphome run voltas-ac.yaml

4. Add to Home Assistant

The device auto-discovers via the ESPHome integration.

Home Assistant Entities

Entity	Type	Controls
Voltas AC	Climate	Temperature, Mode, Fan, Swing
AC Display	Switch	LED display on/off
Status	Binary Sensor	Online/offline
WiFi Signal	Sensor	Signal strength
Uptime	Sensor	Device uptime
Restart	Button	Reboot device

Protocol (Decoded)

The Voltas remote sends a 6-byte frame with 38kHz carrier:

[B2] [4D] [fan_byte] [~fan_byte] [temp_mode] [~temp_mode]

Field	Encoding
Bytes 0-1	0xB2 0x4D — Device ID (constant)
Byte 2	Fan speed: BF=Auto, 9F=Low, 5F=Med, 3F=High
Byte 3	Bitwise complement of Byte 2
Byte 4	(temp_code << 4) | mode_nibble
Byte 5	Bitwise complement of Byte 4

Temperature uses a Gray-code-like lookup (offset from 17°C). Mode nibbles: 0=Cool, 4=Dry, 8=Auto, C=Heat.

Arduino Uno (Testing)

The voltas.ino sketch provides a serial command interface (115200 baud) for testing with an Arduino Uno + IR LED on pin 4:

POWER_ON / POWER_OFF       TEMP <17-30> / TEMP_UP / TEMP_DOWN
MODE <COOL|DRY|HEAT|FAN|AUTO>   FAN <AUTO|LOW|MED|HIGH>
SWING_ON / SWING_OFF       LED_ON / LED_OFF
STATUS / HELP

Note: The Arduino sketch uses static signal arrays (pre-decoded protocol). For production use, prefer the ESPHome component which generates signals dynamically.

License

MIT License — Use freely, just keep the credit.