OEM Carrier 40VA Control Transformer for Model C50A302564 — Part# HT01BD702

This OEM control transformer (part# HT01BD702) is the factory-specified replacement for the Carrier C50A302564 commercial packaged unit. The transformer steps down 120V primary voltage to 24V secondary output, powering the entire low-voltage control circuit — including the thermostat, contactor coil, gas valve, and control board. When it fails, nothing in the system responds: the thermostat goes dark, the unit won't call for heating or cooling, and a multimeter across the secondary terminals will read 0V instead of 24V.

• Specs: 40VA rating | 120V primary / 24V secondary | Factory-matched OEM windings | Designed for continuous duty in commercial rooftop and packaged unit applications
• OEM vs Generic: OEM transformers are wound to exact VA and impedance specs for the C50A302564 control circuit. Undersized or off-spec generic units can overheat, blow internal fuses, or fail to hold voltage under full control circuit load — leading to nuisance lockouts and repeat service calls.
• Install difficulty: 2/5 — Disconnect power at the disconnect box before servicing. Tools needed: flathead and Phillips screwdrivers, multimeter, wire nuts or spade terminals. Label all wires before removing the old transformer and verify 0V on primary leads before touching terminals.
• Warranty: 1-year OEM factory warranty against defects. In stock and ships same business day from our warehouse.

Compatibility: Engineered as a direct OEM replacement for the Carrier C50A302564 commercial packaged unit. Cross-reference part number HT01BD702 against your unit's data plate and wiring diagram to confirm VA rating and terminal configuration before ordering. Need fitment help? Our HVAC parts specialists verify compatibility before you buy — reach out via chat or phone.