Smart Water Heater Energy Optimiser Kit with ESP32 + Relay
ESP32 Smart Water Heater Energy Optimiser Kit — Automatically Heat Water at the Cheapest Tariff Rate
Every part needed, pre-tested for compatibility, with an AI build companion trained on this exact project. Shipped from Bengaluru in 3-5 days.
Transform your ordinary water heater into a cost-saving smart appliance. This kit lets you build a device that monitors your electricity tariff schedule in real-time, learns the lowest-rate windows, and automatically energises the heating element only when power is cheapest — without sacrificing hot water availability.
What You'll Build
A fully functional, wall-mountable controller that retrofits to any standard water heater. The system reads water temperature at two points, measures actual power consumption via current sensing, syncs time with a crystal-backed RTC, and runs a learning algorithm to exploit the cheapest hourly rates from your utility provider. Data logs are stored on a MicroSD card, and an OLED display shows current status and cumulative savings.
What You'll Learn
- How to interface DS18B20 waterproof sensors for accurate multi-point water temperature measurement
- Reading AC current with an ACS712 hall-effect sensor and calculating true RMS power
- Implementing a real-time clock (DS3231) to schedule operations based on time-of-day tariffs
- Programming an ESP32 to run a tariff-learning algorithm and control high-voltage appliances safely via a relay
Kit Contents
| Component | Quantity |
|---|---|
| ESP32 Dev Board | 1 |
| DS18B20 Waterproof | 2 |
| ACS712 20A | 1 |
| DS3231 RTC | 1 |
| MicroSD Module | 1 |
| 5V Relay Module | 1 |
| 0.96in OLED | 1 |
| LM2596 Buck Converter | 1 |
| 100nF Caps | 10 |
| 4.7kΩ Resistors | 5 |
| 10kΩ Resistors | 5 |
| PCB Prototype Board | 2 |
| Enclosure Box | 1 |
| Soldering Iron | 1 |
| Solder Wire | 1 |
Why Buy This Kit Instead of Sourcing Parts Separately
| Factor | Sourcing Separately | Compoden Kit |
|---|---|---|
| Compatibility checks | You verify every part | Pre-tested as a system |
| Build support | Forums and scattered tutorials | AI companion trained on this exact project |
| Time to first working build | Days of debugging | Hours, with step-by-step guidance |
| Shipping coordination | Multiple sellers, multiple delays | One shipment from Bengaluru in 3-5 days |
Who This Kit Is For
This kit is ideal for B.Tech ECE/EEE students working on energy management capstone projects, electronics hobbyists aiming to cut household electricity bills, and engineers prototyping home automation solutions. It provides a hands-on way to understand time-of-day tariff systems common in Indian urban centres, and how IoT can optimise consumption.
Built and Backed by Compoden
Every Compoden kit ships with an AI build companion trained on this exact project — accessible via a QR code on the box, with WhatsApp and email backup. We've spent 10 years building projects for makers, schools, and institutions across India. If a part fails because of a manufacturing defect, replace it free within 7 days.
What if I get stuck during the build?
Scan the QR code on the box to access your AI build companion trained specifically for this kit. It gives step-by-step debugging, detects common wiring errors, and if you're still stuck, message us on WhatsApp for human backup.
Can this system work with any Indian electricity tariff structure?
Yes. The learning algorithm is configurable for flat, time-of-day, or even demand-based tariffs. You'll calibrate it using your electricity provider's rate schedule through a simple setup menu on the OLED.
Is the relay module sufficient for a standard 15A Indian water heater?
The included 5V relay module is rated for 10A at 250VAC. For a typical 3kW heater drawing ~13A, we recommend upgrading to a 16A relay available separately. The kit's PCB layout includes footprints for both options.
Do I need to code the learning algorithm from scratch?
No. The kit includes pre-written libraries and a sample tariff-learning sketch for the ESP32. You'll adjust parameters like temperature thresholds and tariff slots, but the core logic is ready to upload.
DS18B20 water temp + ACS712 current + RTC schedule learns cheapest tariff window and controls heater relay optimally.
What's in this kit
Choose your assembly option:
- Soldering Kit — 25W soldering iron, 60/40 solder wire, flux, and small perfboard for permanent assembly.
- Breadboard Combo — 800-point full-size breadboard with 65-piece jumper wire pack for solderless prototyping.
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Shipping Information
- Prepaid Orders: ₹75 for orders up to ₹999, FREE shipping above ₹999
- COD Orders: ₹125 shipping + ₹50 COD fee = ₹175 total
- Delivery Timeline: Dispatch in 1-2 days, delivery in 2-7 days depending on location
Returns & Warranty
- 7-Day Return: Manufacturing defects only (approval required)
- Warranty: 7 days from delivery
- Non-Returnable: Batteries, consumables, cut wires, clearance items