OEM Carrier Control Transformer 40VA 200–460V Primary / 24V Secondary for Model TJACCYCRTWOPOS005A00

This OEM Carrier control transformer (part number HT01BD201) is the factory-specified step-down transformer for the Carrier TJACCYCRTWOPOS005A00 HVAC unit. Its job is to convert high-voltage line power — 200V, 230V, or 460V primary — down to a safe 24V AC secondary to power the unit's low-voltage control circuit: thermostat, contactor coil, and control board. When this transformer fails, the entire control circuit goes dark. You'll typically see a completely unresponsive thermostat, a system that won't turn on at all, or hear a low buzzing or humming from the transformer itself with no system response.

• Specs: 40VA power rating | Primary: 200 / 230 / 460V multi-tap | Secondary: 24V AC | 60 Hz | Class 2 control transformer | Tyco / Totaline factory build
• OEM vs Generic: This OEM unit is wound to exact factory VA and voltage tolerances. Undersized or off-tolerance generic transformers can overheat under full control-circuit load, causing nuisance trips or premature failure — particularly in multi-stage systems with zone valves or multiple contactors.
• Install difficulty: 2/5 — Disconnect all power at the breaker before servicing. Tools needed: flathead and Phillips screwdrivers, multimeter (verify 0V before touching terminals), wire nuts or terminal connectors. Label all low-voltage wires before disconnecting. Typical swap time is 20–30 minutes for a qualified technician.
• Warranty: 1-year OEM factory warranty. Ships same business day from our warehouse when ordered before cutoff.

Compatibility: Designed as the direct OEM replacement for Carrier TJACCYCRTWOPOS005A00. Also cross-references part numbers HT01BD201B and CIN-TRAN 2005. Always verify your unit's data plate voltage requirements match the transformer's primary tap before installing. Need help confirming fitment? Our parts team verifies compatibility before you order — order with confidence and get back up and running today.