Washing Machine Water Reuse

I want to use arduino to control 4 12 volt solenoid valves and a pump. Would using a relay board be easy? and if so how would that look. Also, does anyone know of a good flow sensor that works with arduino.

Prototype.PDF (73.6 KB)

Using a 4 relay relay board is handy. Check that the relay current switching capacity matches yhe current drawn by Your valves etc.
Also make sure You have power enought for both the realy board coils and the valves & Co.

Flow sensors are highly nonlinear so knowing the flow rate You want to measure will help You choosing the best sensor.

What is the flow sensor for?

You likely need to put some type of anti-backflow valve on the fresh water pipe, otherwise a leaky or stuck valve can result in pumping wash water back into the water piping. Would probably be better to find a way to route a return hose directly to the washer tub.

Are you trying to implement the old "suds saver" feature that reused the wash water between loads of laundry?

david_2018:
Are you trying to implement the old "suds saver" feature that reused the wash water between loads of laundry?

All that is required there is to extend the end of the drain tube to the bottom of the tub, put machine on Spin" or "end of wash" anywhere the pump operates, then turn off the machine, and it will syphon the water back into the machine.

The cheap flow sensors from Ebay/Aliexpress work fine providing that you have an upstream filter to catch the cotton and polyester threads that have shed from the clothing. Cleaning the filter will probably be a weekly task.

If you want a low maintenance solution solution that doesn't need a filter then you'll need to build a water wheel style sensor that is at least the size of your hand. You can sense rotations using a magnetic sensor.

You should look into using transistors (power FETs) instead of relays.

dodsond18:
I want to use arduino to control 4 12 volt solenoid valves and a pump. Would using a relay board be easy?

Seems a bit pointless to me. A relay is a set of contacts operated by an electromagnet. A solenoid valve is a valve operated by an electromagnet. No point in having a relay, whatever will drive the relay will also drive the solenoid valve directly.