Tempstar Transformer for T8DNL100F14A1 — 115V to 24V 40VA | Ships Today
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Overview
This genuine OEM control transformer (part number 1012722) powers the 24-volt control circuit on the Tempstar T8DNL100F14A1 gas furnace. It converts 115-volt line voltage down to the 24 volts used by the thermostat, gas valve, igniter board, and safety switches, and its 40VA rating supplies enough current to drive every low-voltage load on a single-stage furnace at once. A failed transformer is one of the more common causes of a complete no-heat, no-response furnace: the thermostat goes dark, the board's low-voltage fuse blows, and nothing happens on a call for heat. Humming, a scorched smell, or zero volts at the secondary terminals all point to an internally shorted transformer that must be replaced.
Specifications
| Spec | Value |
|---|---|
| Part Number | 1012722 |
| Type | Control Transformer |
| Brand | Tempstar (ICP / Heil family) |
| Primary Voltage | 115V |
| Secondary Voltage | 24V |
| Rating | 40VA |
| Fit | OEM Replacement |
Compatibility
Factory transformer for the Tempstar T8DNL100F14A1 furnace and a direct service part for equivalent single-stage units across the shared ICP, Heil, Comfortmaker, and Arcoaire platform. Always verify the printed 115V/24V voltages and 40VA rating against your original before installing.
Installation Guide
- Safety First — Disconnect power at the furnace switch and breaker, then verify zero voltage with a multimeter.
- Access — Remove the furnace control/blower service panel to reach the control compartment.
- Document — Photograph the primary and secondary wiring before disconnecting any leads.
- Remove — Disconnect the line and 24V leads and unbolt the transformer from its bracket.
- Install — Mount the new transformer and reconnect primary and secondary leads exactly as photographed.
- Test — Restore power, confirm 24V across the secondary, and verify a normal call for heat.
Signs You Need a Replacement
- Blank thermostat and a furnace that will not start.
- Low-voltage control fuse that blows repeatedly.
- Buzzing or humming coming from the transformer.
- No 24V output measured at the secondary terminals.
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