Tempstar Safety Thermostat Limit Switch for TNLS2030HDE — OEM | Ships Today
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Overview
This OEM safety thermostat (part #51302031100, "TSTAT SAFETY") is a temperature-sensing limit switch that protects your Tempstar TNLS2030HDE unit from overheating and unsafe operating conditions. Unlike a wall thermostat, this safety control mounts inside the unit and opens the circuit when it senses an out-of-range temperature, shutting the system down before damage occurs. A failed safety thermostat can trip prematurely and cause nuisance shutdowns, or fail closed and lose its protective function entirely. Symptoms include short-cycling, the unit cutting out under load, or a system that runs without its safety limit responding. Replacing this control restores correct, code-compliant overtemperature protection.
Specifications
| Spec | Value |
|---|---|
| Part Number | 51302031100 |
| Description | Thermostat, Safety (Limit Switch) |
| Type | Temperature Safety Cutout |
| Brand | Tempstar (ICP / Heil) |
| Fit | OEM Replacement |
Compatibility
Direct OEM fit for the Tempstar TNLS2030HDE unit and related ICP/Heil/Comfortmaker models that use the same safety limit thermostat. Verify the OEM part number on your existing control before ordering.
Installation Guide
- Safety First — Disconnect power at the disconnect and verify zero voltage with a multimeter.
- Access — Remove the service panel to reach the safety thermostat.
- Document — Photograph the wiring and mounting position before disconnecting.
- Remove — Disconnect the leads and unfasten the old safety thermostat from its mounting surface.
- Install — Mount the new control in the same location, ensuring good thermal contact, and reconnect the leads per your photo.
- Test — Restore power and confirm the unit runs and the safety control holds the circuit closed under normal operation.
Signs You Need a Replacement
- Unit short-cycles or shuts down under normal load
- Nuisance trips with no actual overheating
- Safety limit fails to open during an overtemperature event
- Burned, corroded, or loose terminals on the control
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