Is this valve open?

[larbec]

An someone tell me how to tell which way is open and close.

We have a reverse osmosis system under our sink and it started to run slow after the plumber hooked up our dishwasher.

Thanks.

 

[ruddy]

When the blue line on the valves runs parallel with the piping to the device is usually in the open position

 

[larbec]

Thanks. That's what I thought. It seems to be repressurized (if that's a word lol) but runs out slow. We can fill up a 20 oz glass and it starts running real slow Could it be the filters need to be changed?