Generally, you should have a disconnect switch within sight for any utilization equipment.
"within sight" means you can actually see the switch from the equipment, and it's no more than 50 feet away. So, if you can see the pressure switch from the breaker box, then you won't need another disconnect at the equipment.
IF not, then you should install one, and if it's a 240 Volt circuit, you will need a double-pole switch to do the job.
A forum community dedicated to Do it yourself-ers and home improvement enthusiasts. Come join the discussion about tools, projects, builds, styles, scales, reviews, accessories, classifieds, and more! Helping You to Do It Yourself!