I have a hot water tank that can be heated either by my oil boiler or by electricity. There’s a hard-wired switch to enable the electric heating.
Now that I have solar panels and a battery, I’d like to make use of excess solar energy by heating the water electrically—especially on days when a good amount of solar generation is expected.
I’ve come across mentions of the Tuya Timeguard as a possible solution, but it seems a bit pricey. Has anyone found a more affordable or effective setup for this?
Wouldn’t a plain old contractor (relay) do the job? You’d have to find one capable of the maximum current demand. I’ve seen ESP32 relay boards, but if they don’t have the capacity then any smart plug could supply the coil of an off-the-shelf contractor.
That would depend on where you are, what voltage and current you’re working with, and which protocols you prefer (Zigbee, Z-Wave, WiFi). Relay boards and contactors are all available on line.
