8555 solenoid controller

[reefmutt]

Hey Roger, this may be a dumb question but i can't figure out why there are two float switches controlling the solenoid.
I know one turns the solenoid on and off and the other permanently turns it off until the first one opens again..
I'd love an explanation of the mechanics of why this is- what's the rational?
I know it's a safety feature but I'm not sure how it helps...
Thanks for your time!

 

[rvitko]

The first water that comes out of an RO is basically tap water, the idea is that we would run the water as long as possible, if you constantly cycle an RO off and on, the water quality is very low as the dissolved solids migrate back across the membrane once the pressure is off, a DI will remove this, but you then quickly burn through the DI, so we turn it on when the reservoir is empty and off when it is full.

 

[jepuskar]

Hello, regarding the 8555 solenoid...is there a polarity for the wires I need to be concerned about? I will be connecting it to my own 12vdc supply.

thanks,

Jason

 

[rvitko]

Their is no polarity, however, their is a directional arrow for flow that is very important and it is marked on the brass, against the flow direction the pressure will eventually cause it to leak and fail. It also needs at least 1200mA.

 

[jepuskar]

Thank you Roger. Very helpful.

Jason