{"product_id":"castair-psh4mix","title":"Castair PSH4MIX","description":"\u003cp\u003eThe Castair PSH4MIX is the full-featured version of the 145-175 PSI pressure switch lineup. It includes a built-in unloader valve, an on\/off lever for manual control, and a four-way valve port configuration. This is the switch you need when your compressor system requires independent control of multiple circuits from a single pressure switch, or when the pump manifold has a four-port connection. If you are just replacing a failed switch on a standard two-port setup, look at the PSH1X or PSH1MIX first — the PSH4MIX is for systems specifically plumbed for four-way operation.\u003c\/p\u003e\n\n\u003ch2\u003eWhat the Four-Way Configuration Means\u003c\/h2\u003e\n\u003cp\u003eA standard pressure switch has one unloader port. The four-way version adds additional ports for systems that route unloader air to multiple pump heads, duplex compressor setups, or specialized manifold configurations. On duplex units running two pumps from a shared tank, the four-way valve allows both pump heads to unload simultaneously from one switch. This keeps head pressure off both cylinders at shutdown and ensures clean motor restarts on both units.\u003c\/p\u003e\n\n\u003ch3\u003eKey Features\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eOperating range:\u003c\/strong\u003e 145 PSI cut-in \/ 175 PSI cut-out — high-pressure shop range\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUnloader valve:\u003c\/strong\u003e Included — bleeds head pressure at shutdown for unloaded motor restarts\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOn\/Off switch:\u003c\/strong\u003e Manual lever on switch body for controlled shutdown without cutting power at the panel\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFour-way valve configuration:\u003c\/strong\u003e Multiple unloader ports for duplex or multi-head pump systems\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCorrosion resistant cover:\u003c\/strong\u003e Protects electrical contacts in shop environments\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEasy to adjust:\u003c\/strong\u003e Cut-out and differential adjustable without special tools\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUL\/CSA listed:\u003c\/strong\u003e Meets commercial electrical safety standards\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eFull Castair Pressure Switch Lineup — 145-175 PSI Range\u003c\/h2\u003e\n\u003cp\u003eCastair builds four variants at 145-175 PSI. Choose based on what your system actually requires:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePSH1\u003c\/strong\u003e — 145-175 PSI, no unloader (use only on compressors with separate unloader)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePSH1X\u003c\/strong\u003e — 145-175 PSI, with unloader (most common single-phase replacement)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePSH1MIX\u003c\/strong\u003e — 145-175 PSI, with unloader and on\/off lever\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePSH4MIX\u003c\/strong\u003e — 145-175 PSI, with unloader, on\/off, and four-way valve (this unit)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003e95-125 PSI Equivalent\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePSL4MIX\u003c\/strong\u003e — 95-125 PSI version of this switch with the same four-way, on\/off, and unloader configuration\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhen Do You Need the PSH4MIX?\u003c\/h2\u003e\n\u003cp\u003eOrder the PSH4MIX when your compressor has a four-port manifold connection on the pump head or when you are running a duplex setup where two pump heads share one pressure switch. If your system only has a single unloader port, the PSH1X or PSH1MIX is the right call — you do not need the four-way ports. If your existing switch has an on\/off lever and multiple unloader ports at 145-175 PSI, the PSH4MIX is your direct replacement.\u003c\/p\u003e\n\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart Number:\u003c\/strong\u003e PSH4MIX\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer:\u003c\/strong\u003e Castair (Cast Air)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePressure range:\u003c\/strong\u003e 145-175 PSI\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUnloader valve:\u003c\/strong\u003e Yes, included\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOn\/Off switch:\u003c\/strong\u003e Yes, manual lever\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eValve configuration:\u003c\/strong\u003e Four-way\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCertifications:\u003c\/strong\u003e UL\/CSA listed\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCover:\u003c\/strong\u003e Corrosion resistant\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhat's in the Box\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e1x Castair PSH4MIX pressure switch with integrated unloader valve, on\/off lever, and four-way valve ports\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhy Buy From Air Compressor Factory Direct?\u003c\/h3\u003e\n\u003cp\u003eWe stock the complete Castair pressure switch lineup — not just the common single-port models but the specialty four-way configurations as well. If you are not certain whether your system needs the PSH4MIX or a simpler variant, call us before ordering. We can help you identify the right switch from your compressor model number. Free shipping on qualifying orders. Full manufacturer support.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCall 866-217-0063 for quick answers and help!\u003c\/strong\u003e\u003c\/p\u003e","brand":"Cast Air","offers":[{"title":"Default Title","offer_id":53342575132885,"sku":"PSH4MIX","price":89.46,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0622\/8466\/0949\/files\/PSH4MIX_20_26_20PSL4MIX.jpg?v=1772675291","url":"https:\/\/aircompressorfactorydirect.com\/products\/castair-psh4mix","provider":"Air Compressor Factory Direct","version":"1.0","type":"link"}