OEM Carrier Transformer 460V Primary / 24V Secondary 75VA — Model TCHC2550HECMRAY603

This genuine OEM Carrier transformer (part number HT01BD702) is the factory-specified replacement for the TCHC2550HECMRAY603 Carrier packaged or commercial HVAC unit. The transformer steps down 460V line voltage to the 24V AC signal that powers every component in the low-voltage control circuit — including the thermostat, contactor coil, gas valve, and control board. When the transformer fails, the entire control circuit goes dead: the thermostat goes blank, the system refuses to start, and no low-voltage components respond. This is a common single-point failure that disables the entire unit until the transformer is replaced.

• Specs: 460V Primary | 24V Secondary | 75VA rated | Genuine OEM part number HT01BD702 | Factory-matched output tolerance for stable control-circuit voltage
• OEM vs Generic: OEM transformers are wound and insulated to Carrier's exact VA and voltage specifications. Generic alternatives often run at lower VA ratings or looser voltage tolerances, leading to erratic thermostat behavior, nuisance tripping, or premature control board damage.
• Install difficulty: 3/5 — Work must be performed with power fully disconnected at the disconnect and breaker. Tools needed: flathead and Phillips screwdrivers, wire stripper, needle-nose pliers, multimeter to confirm 460V supply and verify 24V output post-installation. Label or photograph all low-voltage wiring before disconnecting. Professional installation strongly recommended on 460V commercial equipment.
• Warranty: 1-year OEM factory warranty on parts. Orders ship same business day from our warehouse when placed before cutoff.

Compatibility: Designed as a direct OEM replacement for Carrier model TCHC2550HECMRAY603. The 460V primary input is specific to commercial 3-phase or high-voltage single-phase systems — confirm your unit's supply voltage on the data plate before ordering. Questions about fitment? Our HVAC parts specialists verify compatibility before every order.