water heater controller


Thread Starter


Currently, I'm doing my final year project about water heating system using solar power. We've come across the controller part after
finishing the haardware part. If any of you know the specific device to control water flow using water temperature, please message ASAP.
Thank you
You have several options - see page:

The unit can be built around any housing. It is a simple on off switch with approx 3 min. delay. The switch is rated at 120 VAC 0.5A
resistive so it can work thru a relay.

OR - we have a solid state relay with built in power supply and a 240v 8A relay.

If that's not good we can build a T/C or RTD that will do the same thing.

At what temp. do you want to switch.

Thanks Bob Hogg [email protected]
You can use a simple temeprature controller or signal conditioner depending on whether you need digital or analog control of the water flow.
Automobile thermostats work in such a way, using something like wax to determine the temperature (range) at which they actuate. I found the following page with a description of how they work, by a change in volume accompanying temperature-caused phase change.


That page also links to a page describing solar-powered vent openers which work on the same principle but (probably?) at lower temperatures
than the automotive variety.

Ken Irving <[email protected]>