Description
Binary HPCO/LPCO pressure switch — R134a, 7/16-20 female
A female-thread R134a binary high-/low-pressure switch that protects the A/C system by cutting the compressor clutch at both pressure extremes. It opens on high pressure at ~384 psi (re-closing near 298 psi) and opens on low pressure at ~28 psi (re-closing near 29 psi), on a 7/16-20 female thread. Cross-references UAC SW 4087C.
Two safety cut-outs in one switch
A binary switch wires into the compressor-clutch circuit and guards both ends of the pressure range on an R134a system:
High-pressure cut-out (HPCO)
Opens the clutch circuit near 384 psi to protect against over-pressure — a blocked condenser, failed fan, or overcharge — and re-closes near 298 psi.
Low-pressure cut-out (LPCO)
Opens near 28 psi so the compressor won't run on a low charge, protecting it from running without enough refrigerant and oil — re-closing near 29 psi.
One switch, one circuit
Both functions combined, keeping the clutch engaged only within the safe operating band.
Know exactly what you're ordering
Protect the compressor & the system
Dual protection
High- and low-pressure cut-out in one switch guards against both over-pressure and low-charge damage.
7/16-20 female
Threads onto a 7/16-20 male switch port on a drier, accumulator, or line fitting.
R134a calibration
Set for R134a: opens high near 384 psi and low near 28 psi, with re-close points at 298 and 29 psi.
OE interchange
Replaces UAC SW 4087C, FujiKoki SP4087, Omega/Santech MT1045, and more — see the table.
Compact
Small body that fits tight switch-port and line locations.
Simple install
Thread it into the port and wire it into the clutch circuit — a quick, reliable safety add.
Wire it, mount it — or need the male thread?
Male R134a binary switch · 211-5322
Need a male-thread version instead? Same R134a binary function in the male fitting.
View the male version →Receiver-drier with switch port
This female switch threads onto the drier's 7/16-20 male switch port.
View the drier →Pressure switch pigtail
A 2-wire pigtail to connect the switch into your clutch-circuit wiring.
Shop the pigtail →Interchange & cross-reference numbers
| Brand | Part number(s) |
|---|---|
| UAC | SW 4087C |
| FujiKoki | SP4087 · SP408701 |
| Omega | 2930729 · MT1045 |
| Santech | MT1045 |
| Ranshu | 43MT1045 |
| Annex | 23208 |
Technical specs
Binary switch FAQ
What is a binary HPCO/LPCO switch?
What thread does it use?
What are the exact pressure settings?
Is it for R134a?
What does it cross-reference?
Shop binary pressure switches
Browse binary and pressure switches and set your quantities in one place.
| Image | Product Name | SKU | Price | In Stock | Quantity | Add To Cart |
|---|---|---|---|---|---|---|
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Female R134a 1/4 FF binary high-low pressure switch, low opens at 28 PSIG closes at 29 PSIG, high opens at 384 PSIG closes at 298 PSIG | 211-1022 | $14.23 | In stock | ||
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Match your pressure switch before you buy
Send us your OE switch number or your system's thread and cut-out settings and we'll confirm the right binary switch.
Add to cart ↑ Ask a questionAll manufacturer names and part numbers are trademarks of their respective owners and are listed for identification and cross-reference purposes only; their use does not imply affiliation or endorsement. Confirm thread, pressure settings, and application against your system before installing. Recover refrigerant before opening the A/C system.
