Tempstar Low Pressure Switch Assembly for T4H460GKD100 — OEM 1177594 | Ships Today
OEM Guaranteed
Same-Day Ship
30-Day Returns
Secure Checkout
Overview
This OEM low pressure switch assembly (part number 1177594) is the refrigerant-side safety control for the Tempstar T4H460GKD100. Wired into the 24V control circuit, the low pressure switch continuously monitors suction-line pressure and opens to shut the compressor down if pressure drops too low — protecting the compressor from running on a low charge, a restriction, or a frozen coil. When this switch fails or goes out of calibration, you may see the compressor refuse to start, nuisance trips and lockouts, intermittent cooling/heating, or a unit that short-cycles. Restoring a properly functioning low pressure switch keeps the system's safety chain intact and prevents expensive compressor damage from running under low-charge conditions.
Specifications
| Spec | Value |
|---|---|
| Part Number | 1177594 |
| Type | Low Pressure Switch Assembly |
| Brand | Tempstar (ICP) |
| Circuit | 24V Control / Safety |
| Application | Suction-Line Refrigerant Protection |
| Fitment | OEM Exact-Fit |
Compatibility
Direct OEM replacement for the Tempstar T4H460GKD100 and related ICP/Heil/Tempstar/Comfortmaker units specifying low pressure switch 1177594. Verify the part number, fitting type, and pressure rating against the original before installing.
Installation Guide
- Safety First — Disconnect power at the outdoor disconnect and verify zero voltage with a multimeter.
- Access — Remove the service panel to reach the refrigerant lines and control wiring.
- Document — Photograph the switch leads and mounting location before disconnecting.
- Remove — Disconnect the 24V leads; if the switch is on a Schrader/access fitting, unthread it (recover refrigerant first if the connection is brazed or open).
- Install — Thread on the new switch with a fresh gasket/seal, reconnect the control leads per your photo, and check for leaks.
- Test — Restore power and confirm the compressor energizes on a call with the safety circuit closed and no nuisance trips.
Signs You Need a Replacement
- Compressor won't start and the control circuit reads open
- Nuisance lockouts or repeated safety trips
- Short-cycling or intermittent cooling/heating
- Switch fails to reset after pressure normalizes
Shipping & Returns
Ships same day before 3 PM CST. 30-day returns. Backed by the National HVAC Parts fitment guarantee.
Shipping Information
- Orders placed before 3PM CST ship same business day
- Standard delivery: 2-5 business days
- Express shipping available at checkout
- Free shipping on orders over $75
- Tracking number emailed upon shipment
Return Policy
- 30-day returns on unused parts in original packaging
- Electrical parts (capacitors, contactors, control boards) are final sale once installed
- Email info@nationalhvacparts.com to initiate a return
- Refunds processed within 5-7 business days