{"product_id":"carrier-py3pna030040nb-control-board-cyc67p","title":"OEM Carrier DSI Control Board LH33WP003 for PY3PNA030040NB","description":"\u003ch1\u003eOEM Carrier Direct Spark Ignition (DSI) Control Board LH33WP003 for Model PY3PNA030040NB\u003c\/h1\u003e\u003cp\u003eThis is the genuine OEM Carrier \u003cstrong\u003eLH33WP003\u003c\/strong\u003e Direct Spark Ignition (DSI) Control Board — the factory-specified replacement for the \u003cstrong\u003eCarrier PY3PNA030040NB\u003c\/strong\u003e packaged rooftop unit. The DSI control board is the central intelligence of your unit's heating system: it sequences the inducer motor, fires the spark igniter, opens the gas valve, verifies flame presence, and orchestrates the blower motor — all while continuously monitoring safety limit switches and pressure switches. When this board fails, symptoms typically include a no-heat lockout condition, the unit attempting ignition and immediately faulting out, erratic blower behavior, or a complete failure to respond to a heating call from the thermostat.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart Number \u0026amp; Type:\u003c\/strong\u003e Carrier OEM Part # LH33WP003 (also supersedes LH33WP003A) | Direct Spark Ignition (DSI) microprocessor-based control board\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOEM vs Generic:\u003c\/strong\u003e This is the genuine factory-authorized Carrier board — engineered to exact OEM tolerances for the PY3PNA030040NB. Aftermarket substitutes may lack precise ignition timing sequences (pre-purge, trial-for-ignition, retry, and post-purge cycles) matched to your unit's heat exchanger design, risking nuisance lockouts or premature component wear.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eInstall Difficulty: 4\/5\u003c\/strong\u003e — Requires disconnecting 24V control wiring, line-voltage blower and inducer leads, and flame sensor\/spark igniter harnesses. Always cut power at the disconnect before beginning. Tools needed: flathead and Phillips screwdrivers, needle-nose pliers, smartphone camera (photograph all wiring before removal), and a multimeter to verify 24V at the transformer secondary before condemning the board.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWarranty \u0026amp; Shipping:\u003c\/strong\u003e Backed by Carrier's OEM factory warranty. In stock — ships same business day from our warehouse so your equipment is back online fast.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Engineered for the Carrier \u003cstrong\u003ePY3PNA030040NB\u003c\/strong\u003e packaged rooftop unit. Verify your existing board's part number on the board label or your unit's wiring diagram before ordering. Cross-references include superseded suffix variant LH33WP003A. Need fitment help? Our HVAC parts specialists confirm compatibility before you buy.\u003c\/p\u003e","brand":"Carrier","offers":[{"title":"OEM","offer_id":62640395714931,"sku":"CARRIE-PY3PNA030040NB-CONTROL_BOARD-LH33WP003","price":562.95,"currency_code":"USD","in_stock":true},{"title":"Generic","offer_id":62640395747699,"sku":"CARRIE-PY3PNA030040NB-CONTROL_BOARD-LH33WP003-GEN","price":494.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0984\/1190\/5395\/files\/nhvac-control-board-LH33WP003_521e44d0-539c-4734-a9da-091adc213a5c.jpg?v=1775028119","url":"https:\/\/nationalhvacparts.com\/products\/carrier-py3pna030040nb-control-board-cyc67p","provider":"National HVAC Parts","version":"1.0","type":"link"}