OEM Carrier 40VA Control Transformer 208/240V to 24V for Model SUBCLR50HJ440030

This is the genuine OEM Carrier control transformer (part number HT01BD209), the factory-specified replacement for the SUBCLR50HJ440030. The transformer steps down line voltage from 208/240V to the 24V needed to power your thermostat, control board, and all low-voltage system components. When this part fails, the entire control circuit loses power — the result is a completely unresponsive system: no thermostat display, no contactor pull-in, and no heating or cooling whatsoever. A quick 24V check at the transformer's secondary terminals with a multimeter will confirm whether this part is the culprit.

• Specs: 208/240V Primary | 24V Secondary | 40VA rated | 50/60 Hz | Class 2 control transformer | Replaces OEM part numbers HT01BD207, HT01CN232, and 9076-00
• OEM vs Generic: OEM transformers are wound to exact factory VA ratings, ensuring the secondary stays at a stable 24V under full load. Undersized or off-brand units can sag under load, causing intermittent lockouts, nuisance tripping, and premature control board failures.
• Install Difficulty: 2/5 — Shut off all power to the unit before starting. Tools needed: multimeter, flathead and Phillips screwdrivers, wire stripper, and insulated terminals. Label each wire before disconnecting. Verify 24V output at secondary terminals before closing the panel.
• Warranty: 1-year OEM factory warranty. Ships same business day from our warehouse — in stock and ready to go.

Compatibility: Designed as a direct OEM fit for Carrier model SUBCLR50HJ440030. Cross-references HT01BD207, HT01CN232, and 9076-00. Always verify your unit's existing transformer specs (input voltage, output voltage, and VA rating) against your data plate before ordering. Our parts specialists are available to confirm fitment — just reach out before you buy.