Tempstar 40VA Transformer for TCH948GKA100 — 208/230V to 24V | Ships Today
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Overview
This OEM control transformer (Tempstar part number 1170676) steps 208/230V line power down to 24V at 40VA and is the factory replacement for the Tempstar TCH948GKA100. The transformer supplies low-voltage power to the contactor coil, the thermostat circuit, and the unit's safety controls — essentially everything that tells the equipment when to run. When a transformer fails, opens, or shorts, the entire 24V control circuit goes dead: the contactor will not pull in, the thermostat loses power, and the system stops cooling even though high-voltage power is present. A transformer that buzzes loudly or runs hot is also on its way out. Installing the correct 40VA OEM transformer restores full control-circuit operation.
Specifications
| Spec | Value |
|---|---|
| Part Number | 1170676 |
| Type | Step-Down Control Transformer |
| Brand | Tempstar |
| Primary Voltage | 208/230V |
| Secondary Voltage | 24V |
| Rating | 40VA |
| Fits Model | TCH948GKA100 |
Compatibility
Direct OEM fit for the Tempstar TCH948GKA100 and equivalent ICP-built Heil and Comfortmaker units that use a 208/230V-to-24V 40VA control transformer. Confirm primary/secondary voltage and VA rating against your existing transformer before ordering.
Installation Guide
- Safety First — Disconnect power at the disconnect and breaker, then verify zero voltage with a multimeter.
- Access — Remove the unit service panel.
- Document — Photograph the primary (line) and secondary (24V) wire connections before disconnecting.
- Remove — Disconnect the leads, unbolt the transformer from its mounting bracket, and lift it out.
- Install — Mount the new 40VA transformer, then reconnect the 208/230V primary and 24V secondary leads exactly per your photo.
- Test — Restore power and confirm a steady 24V at the secondary and a clean contactor pull-in.
Signs You Need a Replacement
- No 24V at the control circuit while line voltage is present
- Contactor will not energize and thermostat is dead
- Transformer buzzes loudly or runs very hot
- Repeated blown low-voltage fuses traced to a shorted transformer
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