Has anyone successfully installed a wireless controller for an electric water heater (240V)? Just as importantly, please share your experience if you tried, and didn't have success.
How handy are you? You can purchase this contactor to make your project work. https://amazon.com/dp/B004Z0RLL2/ref=pd_lpo_sbs_dp_ss_1?pf_rd_p=1944687542&pf_rd_s=lpo-top-stripe-1&pf_rd_t=201&pf_rd_i=B00O3UBOMG&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=5TWDV6AW22E8XK22DHP0
This model requires 120 (with neutral) to switch and 220/240 power to pass through. You can turn it on and off with a smart switch on the 120 side.
There is a small load when switch is energised.
@fbpeters, the normally open (NO) contacts need the coil energized to close. In this manner when power goes out (or is switched off) the contacts open and the load (heater) will turn off. If you use normally closed (NC) contacts you will need to turn something on to shut off the heater. It will still work fine but will be difficult to automate through devices that are automatically turned off, though not impossible. If you just want remote manual control this will work fine, but you want to make sure the remote device is not linked with OC. Also, be sure that the contactor you select is rated for the full load amps that your water heater uses, and is properly installed per code requirements (enclosure type, fusing, wire type and protection, etc.).
Thanks very much! Is there a reason that you use a normally open contactor, as opposed to a normally closed type? I guess I would like the water heater to operate normally, and only be turned off when an Ohm hour was called. Is there something I'm missing? I get that there would be current draw due to the switch during the ohm hour, but I imagine it would be small compared to the water heater turning on.
@That Son Of A Bitz I'm not sure why you would need one. You can turn off the main breaker and a gas water heater should continue working, unless there are ones that have pilot-less ignition that needs to be plugged in. They would draw only a little power when igniting the flame.
Hmm, interesting engineering problem. The easy way is an automated gas shutoff valve, but this will turn off the pilot also. Then you would not have hot water until you re-light the pilot flame each time. So you would need to override the thermostat control (challenging but preferred) or install a shutoff valve on the gas line between the heater control and the burner (difficult). There are electronic solenoid valves available designed to work with natural gas, but the modifications required, safety interlocks and potential for gas leaks are significant. I would not recommend it. Better to go to an on-demand type heater.
I found this product online. Has anyone tried using the Aquanta Water Heater Controller.https://aquanta.io/product/aquanta-water-heater-controller/
You can buy a gas water heater that is pilotless, and then you can switch it on and off with a regular 120VAC Internet-connected switch. When the power is turned off, it won't light up. But I don't see the point as far as OhmConnect is concerned, since a gas water heater has an insignificant (or no) effect on electricity use. For an electric water heater, a normally-closed 220VAC contactor makes sense, so it is only operated (energized) when the OhmHour is on...