OEM Guaranteed
Same-Day Ship
30-Day Returns
Secure Checkout
This genuine OEM 40VA control transformer (part number 1173691) with its matching 24V barrier (part number 1178431) steps line voltage down to the low-voltage control circuit on the ICP/Tempstar/Heil WPG3604115LKC1. It accepts a 208/230V primary and delivers a 24V, 40VA secondary that powers the thermostat, gas valve, relays, and control board. When the transformer fails — usually from a shorted secondary, overload, or age — the entire control system goes dead: no thermostat display, no relay action, and no heating or cooling response. The included barrier provides the required insulation and terminal protection for the low-voltage connections.
| Spec | Value |
|---|---|
| Part Numbers | 1173691 (Transformer), 1178431 (24V Barrier) |
| Type | Step-Down Control Transformer |
| Brand | ICP / Tempstar / Heil |
| Primary Voltage | 208/230V |
| Secondary Voltage | 24V |
| Rating | 40VA |
| Fit | OEM Replacement |
Direct-fit OEM replacement for the ICP WPG3604115LKC1 packaged unit and related Tempstar, Heil, and Comfortmaker systems that use a 208/230V-to-24V 40VA control transformer. Confirm primary/secondary voltages and VA rating against your existing transformer before ordering.
Ships same day before 3 PM CST. 30-day returns. Backed by the National HVAC Parts fitment guarantee.