Castair Honeywell Pressure Switch — HON1420
The HON1420 is a Honeywell pressure switch in Castair's replacement parts catalog, used in specific Castair compressor models and configurations. The model number suffix "1420" suggests this may be a higher-amperage switch (14A/20A or a similar rating convention), which would make it appropriate for larger motor control circuits than the HON1010 or HON1012. Pressure switches are the motor's on/off brain — they read tank pressure and control when the motor runs, and when they fail, the entire compressor system either runs non-stop or won't run at all.
Note: Castair does not publish complete electrical specs for the HON-series switches on their website. Call 866-217-0063 and provide your compressor model number to confirm the HON1420 is the correct switch before ordering.
Pressure Switch Operation — What You Need to Know for Replacement
When replacing a pressure switch, four things need to match your compressor's requirements:
- Pressure Range: The cut-in and cut-out setpoints must match your compressor's intended operating pressures. Low-range switches (95/125 PSI) go on shop compressors; high-range switches (145/175 PSI) go on industrial units. Wrong range and your tank either underinflates or overloads the safety valve.
- Amperage: The switch must handle the full-load amperage of the motor. Undersized switch contacts burn and weld shut. The HON1420's suffix suggests a higher amperage rating suitable for larger motors.
- Phase: Single-phase and three-phase switches have different contact configurations. Using a single-phase switch on a three-phase motor leaves one leg of the motor uncontrolled.
- Unloader Port: If your compressor uses a centrifugal unloader or a pressure-actuated unloader valve, the switch needs an unloader port. Without it, the motor has to start against full head pressure, which exceeds starting torque on larger pumps.
HON1420 Pressure Switch Features
- Honeywell Quality: Industrial pressure switch construction designed for repeated high-cycle operation in compressor control applications
- Corrosion Resistant Cover: Protects contacts and adjustment mechanism from shop-environment humidity, oil mist, and contamination
- UL/CSA Listed: Meets North American electrical safety standards
- Castair Specified: Factory-sourced switch for Castair compressor installations requiring this model
When to Replace a Pressure Switch vs. Adjusting It
Before ordering a replacement switch, try these checks:
- If the compressor runs but won't shut off at the correct pressure, the cut-out adjustment may have drifted — try adjusting the main spring nut before replacing the switch
- If the compressor won't start even with an empty tank, check the cut-in setting and verify the contacts are not stuck open with a continuity check at low pressure
- If there is visible burning on the contacts, or the switch housing is cracked or melted, replacement is the correct action — adjustment won't fix damaged contacts
- If the switch has water or oil inside the housing, replace it — moisture contamination permanently degrades contact reliability
Castair Pressure Switch Lineup
- PSL1 / PSL1X / PSL1MIX / PSL4MIX — 95-125 PSI range, various configurations
- PSH1 / PSH1X / PSH1MIX / PSH4MIX — 145-175 PSI range, various configurations
- PSAD15-230 — Wide-range adjustable, 15-230 PSI
- HON1010 / HON1012 / HON1420 — Honeywell OEM switches for specific Castair configurations
- PSUV — Pressure switch unloader valve (replacement unloader valve for switch body)
What's in the Box
- 1 x Honeywell pressure switch (HON1420)
Technical Specifications
- Part Number: HON1420
- Brand: Honeywell (sold through Castair)
- Category: Pressure switch — motor control for air compressors
- Electrical Ratings: Call 866-217-0063 for current specifications
- Pressure Range: Call 866-217-0063 and provide your compressor model number
Why Buy From Air Compressor Factory Direct?
We have specialized in Castair compressors and parts since 2016. Pressure switch compatibility is model-specific — getting the right switch matters for motor protection and compressor longevity. We can cross-reference your compressor model number to confirm the HON1420 is correct for your application before you order. Free shipping, free tech support at 866-217-0063, full Castair warranty.
Call 866-217-0063 for quick answers and help!
