The Castair PSL1MIX is a 95-125 PSI pressure switch that includes both an unloader valve and a manual on/off lever. It is the most practical configuration for a shop compressor running in the standard 95-125 PSI range: the unloader valve protects the motor from restarting against head pressure, and the on/off lever lets you shut the compressor down properly without walking to the breaker panel. At $40.73, it is just four dollars more than the PSL1X and gives you manual on/off control that most shop owners appreciate on a daily-use compressor.
Why the On/Off Lever Matters
A pressure switch with an on/off lever gives you a proper shutdown point. You flip it off, the compressor stops, and it will not restart even if pressure drops below cut-in. This is how you properly shut down a compressor at the end of the day — not by waiting for the motor to cycle off and then cutting the disconnect. The lever also lets you hold the compressor off during maintenance without locking out the entire circuit. On a compressor used throughout the workday by multiple people, the lever is useful for quick, clean shutdowns without interrupting other shop circuits on the same panel.
Key Features
- Operating range: 95 PSI cut-in / 125 PSI cut-out
- Unloader valve: Included — bleeds head pressure at shutdown for clean motor restarts
- On/Off lever: Manual control lever on switch body for proper shutdown and service lockout
- Corrosion resistant cover: Protects contacts in shop environments
- Easy to adjust: Differential and cut-out settings field-adjustable
- UL/CSA listed: Commercial electrical safety certification
Pressure Switch Lineup — 95-125 PSI
- PSL1 — No unloader, no on/off ($36.31)
- PSL1X — With unloader, no on/off ($39.85)
- PSL1MIX — With unloader and on/off lever ($40.73) — this unit
- PSL4MIX — With unloader, on/off, and four-way valve (duplex/multi-head)
When Do You Need the PSL1MIX vs. PSL1X?
If your existing switch has a lever that you flip to turn the compressor on and off, replace it with the PSL1MIX. The PSL1X does not have the lever — it only pressure-cycles automatically. On a compressor used throughout the workday where you want clean on/off control from the compressor itself, the MIX configuration is the right choice for four dollars more. If your setup is automated (motor starter, timer control), the PSL1X is simpler and sufficient.
Technical Specifications
- Part Number: PSL1MIX
- Manufacturer: Castair (Cast Air)
- Pressure range: 95-125 PSI
- Unloader valve: Yes
- On/Off switch: Yes, manual lever
- Certifications: UL/CSA listed
- Cover: Corrosion resistant
- Price: $40.73
What's in the Box
- 1x Castair PSL1MIX pressure switch with integrated unloader valve and on/off lever
Why Buy From Air Compressor Factory Direct?
We stock the complete Castair switch lineup. If you need to confirm which switch your compressor originally had, we can help — call us with the compressor model number and we will get you to the right part. Free shipping on qualifying orders. No substitutions, no knockoffs.
Call 866-217-0063 for quick answers and help!
