Can I plug port number three on my 3-way valve and make it into a 2-way?
No.

Can I convert a 3-way normally closed valve to a 3-way normally open valve?
No. The internal passages and parts of a 3-way normally closed valve are shaped differently than those of a 3-way normally open valve.

Can I operate my 120 Volt / 60 Hz valve on DC current?
Some AC solenoids are dual rated, meaning that there is a corresponding DC voltage that would also work for that particular solenoid. However, this corresponding DC voltage is usually approximately half of the AC voltage in question. In most of these cases, the two rated voltages are stamped on the solenoid coil. If your solenoid is not so marked, consult ROSS before attempting to use any other voltage. Also, AC solenoids are equipped with shading rings to reduce buzzing, but solenoids made specifically for DC voltage do not have shading rings. Connecting AC voltage to a DC solenoid, even if the voltage level is correct, will result in a buzzing solenoid. This is not recommended.

How do I convert my line-mount valve to external pilot supply?
This is a simple procedure. Please see page 11 of the "Bulletin 331G Service & Installation Manual" for instructions.

What do the numbers 1, 2, 3, 4, 5, mean on my valve?
These are port markings.

1 is the inlet or supply port

2 is an outlet port

3 is an exhaust port

4 is an outlet port

5 is an exhaust port

What does X-1 and Y-3 mean?
These are pilot port markings.

X-1 is the pilot external supply port

Y-3 is the pilot exhaust port

Can I plug the Y-3 port on my pilot?
No. Plugging the pilot exhaust port will cause erratic valve operation. Please install a 1/8 ported silencer instead.