Tempstar PTAC Thermostat for THB09R50DCA — Low-Temp Control with Knob | Ships Today

Overview

This is the genuine OEM thermostat package for the Tempstar THB09R50DCA PTAC unit, covering the standard PTAC thermostat (OEM 1058517, TSTAT PTAC X), the low-temperature thermostat (OEM 1059022, TSTAT LOW TEMP X), and the matching control knob (OEM 1058437, KNOB TSTAT PTAC X). The thermostat senses room temperature and cycles the compressor, fan, and heat to maintain the setpoint, while the low-temp thermostat provides freeze/low-ambient protection for the chassis. Together these controls keep the unit running safely and accurately. Failed thermostats cause constant running, no-start conditions, short-cycling, or loss of freeze protection.

Specifications

Compatibility

Direct-fit replacement for the Tempstar THB09R50DCA PTAC chassis. These thermostats are shared across matching ICP, Heil, and Comfortmaker PTAC units of this generation. Confirm your existing part numbers before ordering.

Installation Guide

1. Safety First — Disconnect power and verify zero voltage with a multimeter.
2. Access — Remove the front grille and control-area service panel.
3. Document — Photograph all thermostat and low-temp sensor wiring before disconnecting.
4. Remove — Pull the knob, release the thermostat clips, and disconnect both sensing bulbs and wiring.
5. Install — Mount the new thermostats, route each sensing bulb to its original clip, reconnect per your photo, and press on the knob.
6. Test — Restore power and verify operation across cooling, heating, and low-temp protection.

Signs You Need a Replacement

• Unit runs nonstop or fails to start
• No response to the temperature knob
• Loss of freeze/low-ambient protection
• Short-cycling or erratic operation

Shipping & Returns

Ships same day before 3 PM CST. 30-day returns. Backed by the National HVAC Parts fitment guarantee.