ICP 40VA Transformer for WPG4604090RKB1 — 208/230V to 24V | Ships Today
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Overview
This OEM control transformer kit (part numbers 1173691 transformer and 1178431 24V barrier) supplies low-voltage control power for the ICP / Tempstar / Heil WPG4604090RKB1 packaged unit. The transformer steps 208/230V line voltage down to 24V at 40VA, powering the control board, contactor coil, gas valve, and thermostat circuit. The included barrier provides the required separation for the 24V wiring. When a transformer fails — usually from a shorted secondary, overload, or surge — the entire control circuit goes dead: the thermostat screen blanks, the contactor won't pull in, and neither heating nor cooling will start even though line power is present. A blown or buzzing transformer with no 24V output should be replaced with the correct 40VA OEM unit.
Specifications
| Spec | Value |
|---|---|
| Part Numbers | 1173691 (transformer), 1178431 (24V barrier) |
| Type | Step-Down Control Transformer |
| Brand | ICP (Tempstar / Heil) |
| Rating | 40 VA |
| Primary Voltage | 208/230V |
| Secondary Voltage | 24V |
| Application | Low-voltage control circuit |
Compatibility
Direct OEM replacement for the ICP / Tempstar / Heil WPG4604090RKB1 packaged unit and other ICP-family models that use the 40VA, 208/230V-to-24V control transformer. Verify your primary and secondary voltages and the VA rating against the 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 control compartment service panel.
- Document — Photograph the primary and secondary lead connections before disconnecting.
- Remove — Disconnect the leads, then unbolt the transformer and barrier from the mounting bracket.
- Install — Mount the new transformer and barrier, connect the matching primary taps for your supply voltage, and wire the 24V secondary per your photo.
- Test — Restore power and confirm 24V at the secondary and normal heating/cooling operation.
Signs You Need a Replacement
- Blank thermostat with no 24V control power
- Contactor and gas valve won't energize on a call
- Burned, buzzing, or visibly overheated transformer
- Repeatedly blown low-voltage fuse after a short
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