Smart Water Heater

Projects General Guidance
1

This mission for knowledge came after a buddy suggested I get a timer for my water heater, and said I couldn't get one for under a hundred bucks.

My goal is to come up with the most inexpensive device, that will activate the water heater on a schedule, and record it's power consumption.

Arduino Board - Not sure which one to get. Cheapest one that'll do the job for now. I read I could program a chip using an arduino board, and use that for an even cheaper version.
220Vac - 12VDC 1A transformer = $3.40
220VAC 40A DPDT Relay = $6.80
ACS712 Module Current Sensor 220Vac 30A = $6.99
LCD Display with keypad = $3.48

$20.67 without the board, just on a quick part/price search.

Am I on the right track as far as the parts I'd need?

Any guidance would be greatly appreciated.

2

"ACS712 Module Current Sensor 220Vac 30A"

Where does it say "220Vac".

Leo..

3

Low power consumption, low price: these guys are hard to beat when it comes to switching. Power consumption not included yet, though.

Dremmer:
Am I on the right track as far as the parts I'd need?

Hard to say.
I take it you're on 220V AC, single phase? That would make it a boiler type, rather than an instant on type. What's the rated power of your heater? What kind of on/off schedule do you need?

4

and said I couldn't get one for under a hundred bucks.

Heavy duty and reliable 10 kW water heater timer for $40

5

Dremmer:
$20.67 without the board, just on a quick part/price search.

Am I on the right track as far as the parts I'd need?

http://www.ebay.com.au/itm/DIN-Rail-Digital-LCD-Power-Programmable-Timer-Time-Switch-Relay-AC-220-240V-FA1-/112415481460?epid=902971182&hash=item1a2c7c1e74:g:yw8AAOSw42dZIqbG
$AU 15.88, and battery backup included at no extra charge.