Shelly 1PM Gen4 smart relay for water heaters, heaters, lights and outlets

Wiring the Shelly 1PM Gen4 with a two-way switch

Wiring the Shelly 1PM Gen4 to control an outlet

Wiring the Shelly 1PM Gen4 to a water heater

Wiring the Shelly 1PM Gen4 to a lighting circuit

Smart water heater switch: hot water at the touch of a button

Forget the old way of heating water. Meet the new generation of water heating control: a smart switch for your electric water heater that changes the way you heat water at home.

What is a smart water heater switch?

A smart water heater switch is more than just another electrical switch replacing the old water heater button. It’s advanced technology that gives you full remote control of your electric water heater from a smartphone app, a tablet or even by voice. Today’s smart relays are the new generation of the water heater switch, with capabilities that simply weren’t possible before.

Unlike a regular water heater switch, which you have to be standing next to, a smart water heater switch lets you control water heating from anywhere: the living room couch, the office or even on vacation. That way you can make sure you always have hot water exactly when you need it, without wasting electricity on unnecessary heating.

The benefits of a smart switch for your electric water heater

A smart switch for your electric water heater offers a range of benefits that make everyday life more comfortable and efficient:

• Remote control, anytime: turn the water heater on or off, or schedule it, from anywhere with the app. On your way home from work? Turn it on 20 minutes before you arrive, and the water will be hot when you walk in.
• Energy monitoring: the smart switch measures power consumption in real time, so you can see how much energy the water heater uses, estimate the monthly cost and spot inefficient usage patterns.
• Smart scheduling and advanced automation: set up routines that run automatically, such as turning the water heater on every morning half an hour before you wake up, turning it off automatically after two hours, or turning it on Friday ahead of the weekend.
• Smart home integration: a smart water heater switch integrates easily with other smart home systems and can be part of more complex scenes, like “Going to sleep” (water heater off, lights off, alarm on).
• Significant electricity savings: because you control exactly when the water heater runs, you can cut water-heating electricity costs by up to 30%. Today’s smart relays include an accurate meter, so you can track your actual savings.
• Improved safety: get real-time alerts about faults, excessive consumption or sudden power loss. Built-in overload and overheating protection improves safety and extends the life of the water heater.
• Advanced fault diagnosis: catching potential problems early can prevent costly damage to the water heater and to your home’s electrical system.

Advanced technology in a smart water heater switch

Smart switches for electric water heaters are packed with technology that puts them at the forefront of their category:

• Tank water temperature measurement: heat water efficiently, only as needed, to save electricity.
• Accurate metering: advanced measurement sensors provide highly accurate, real-time data on power consumption.
• Compact size: thanks to their small size, the relays fit easily behind existing switches with no changes to the electrical wiring.
• Rated for high loads: suitable for large, high-power electric water heaters.
• Built-in protection: protection against overheating, overload and short circuits for maximum safety.
• Broad compatibility: works with Alexa, Google Assistant and Apple HomeKit, and is ready for the new Matter standard for unified connectivity between smart home devices.

Simple installation and everyday use

Installing a smart switch for an electric water heater is relatively simple and can be done by any licensed electrician. The relay is wired between the existing water heater switch and the water heater itself, and in most cases no changes to the existing wiring are needed. Once it’s installed, download the app (available in Hebrew), connect the relay to your home network and enjoy full control of your water heater.

For everyday use, the app offers a simple, intuitive interface that lets you:

• Turn the water heater on and off instantly
• Set timers and fixed run times
• View power consumption statistics
• Create complex automations and scenes
• Get real-time alerts and notifications

OZZI: a leader in the smart home

At OZZI, we’re proud to be one of Israel’s leading smart home solution providers, with a strong focus on energy savings and comfort. The smart water heater switch we sell is a leader in its category, combining quality, reliability and value for money.

We offer full technical support, detailed guides and personal advice on choosing the right solution for your needs. Our smart home experts are happy to answer any question and help with every aspect of installation and use.

Gen3 or Gen4?

Both models fit behind the switch, handle up to 16 A and measure power consumption. They suit water heaters, air conditioners, heaters, lighting and outlets. Gen4 adds Zigbee and Wi-Fi 6, so it also connects to Zigbee hubs and other smart home systems. The Shelly 1PM Gen3 is a good fit if you only use the Shelly app. All models are in the smart relay category.

Before you install

• Requires a neutral wire in the wall box (for homes without a neutral, see the Shelly 1L Gen3).
• Up to 16 A. For a water heater over 3,500 W, use a contactor.
• For a water heater that comes with a temperature probe: the smart water heater kit.

FAQ

Can the water heater turn off automatically?

Yes, on a schedule or after a set time. With the kit, it can also turn off based on water temperature.

Can I see how much the water heater costs to run?

Yes. Enter your electricity rate in the app to see the cost by day and by month.

Does the wall switch keep working?

Yes, even without internet.