All,

I'm looking for a cheap source for a electrically controlled solonoid
control valve. I've found washing machine water inlet valves as cheap
as $12.00. I want to build a cooling system that will swich the output
of a pump to up to several different outputs. When I first saw the
water inlet valves, I thought GREAT! all I have to do is hook my pump
output to the inlet valve output. That way, I'd get two valves for one
water inlet valve (one from the hot water input and another from the
cold water input).
After digging into it a little bit, I found out that the flow through
these valves is only one way and that at least 30PSI is required in the
proper direction.

My Question:

Is this true for all water inlet valves?
Why? Is there a check valve in there?
If so, can I disable it somehow?

Any help is appreciated.