Smart SMS Powered Water Heater Using LinkitONE




Introduction: Smart SMS Powered Water Heater Using LinkitONE

About: I build products which solve real world problems.

Want to make your water heater start heating of water on SMS? Imagine you are out, and you are coming back home. Then won't you like if you just sms a string and your water heater gets on !

Here i'll show you how you can build a simple SMS powered water heater using your LinkitONE board!

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Step 1: What Do You Need?

1 . LinkitONE board

2. Water heater

3. Breadboard

5. LinkitONE GSM antena

6. Battery pack

7. Relay module

Step 2: Hacking Into the Water Heater!

Now let's hack into the water heater!

We'll need to find places where we can connect a relay. So keep searching for for places where you can attach a simple relay. It could be your plug socket, or a wire joint. Once you find that, move to the next step.

Step 3: Attaching a Relay

Now attach a relay to the system. Just take out the power plug, fix the relay into the breadboard, and tape up everything.

Be careful as you are dealing with high voltage!!!

Step 4: Attaching the Board

Now attach your LinkitONE!

Carefully attach it to the relay and then wire it up. Once done, check the connections twice because there should be no chance of short circuit.

Step 5: Writing Some Code

Now we'll write some code.

The code is really simple here! We're waiting to receive an SMS, once we get an SMS, we read it, if the string is "on" then we turn on the water heater. It's as simple as that



#include <LGSM.>

void setup()

{ pinMode(13,OUTPUT);


boolean notConnected = true;




void loop() {

String msg;


{; //reading sms




else if(msg.equalsIgnoreCase("OFF"))



Now burn the code and move to the next step!

Step 6: Finalizing Everything

Finalize everything by connecting your GSM/SMS antenna and tightening it up. Carefully do it as all the parts are really brittle and can break easily.

Step 7: Testing It Out!

Now test it out!

Try sending a simple SMS and see the magic! :D

Congrats! You've made your own SMS powered water heater.

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    6 Discussions


    4 years ago

    How is the number to send sms?


    4 years ago

    Hi, nice job, I like the way you control something with sms but I think your relay is a bit "light", just for your safety. Why not set a timer so you heat your water for a couple of hours and it switches off automatically so you won't waste money if you forget to switch it off.


    Reply 4 years ago

    Exactly, very good point


    4 years ago

    It's a great idea, but be careful. There are several safety issues that need to be addressed. Specially when you're designing something you'll be operating remotely:

    1st. The relay is only rated at 5A. I'm not sure about your heater, but several of them are way over 1100Watts. You need a beefier one in order to switch the current the heater will demand.

    2nd. the wires you're using to connect the relay need to be, at least, the same gauge of the original ones. A water heater draws a lot of current, so, if you use a very thin cable, it'll work as a fuse (it will burn, posing a fire hazard).

    3rd. Since you're using this in a wet environment like the bathroom, you need some enclosure in order to protect it from the humidity. First for safety (so you don't get electrocuted) and second for durability of your device (corrosion).

    I don't like to be a downer, but operating the device as described it's very very dangerous. I understand that it might be a "proof of concept", but you have to think that somebody without your knowledge might want to replicate it exactly as you described.

    Other than that, I think it's a good idea. It must suck waiting for the water to heat, and this is a good idea.