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Pickup available at 75 Blue Mountain St #3, Coquitlam
Usually ready in 24 hours
Not sure this fits your furnace? Call us — we're happy to help
This advanced HVAC control board is a vital component for managing the ignition and operation of 1-stage heating systems. Featuring Communication Version 4.4, this circuit board facilitates seamless data exchange between system components to ensure optimal performance and energy efficiency. As an ignition modulating control, it regulates the heating cycle, monitors safety sensors, and manages blower timing to maintain a comfortable indoor environment. If your furnace or air handler is experiencing startup failures or communication errors, this replacement control module is designed to restore reliable system operation and precision control over your appliance's heating functions.
Our team is happy to help you verify compatibility before you order. We'll confirm it fits your specific furnace model.
1-778-759-9864Mon–Sat 8AM–5PM PT · Or email parts@bcfurnace.com
Compatible parts and related replacements
Yes. The 121-678 is a genuine York OEM part, sourced from an authorized York parts distributor. This Control Board is backed by our 100% compatibility guarantee — if it doesn't fit your furnace, we'll make it right.
The easiest way is to match the part number (121-678) with your furnace model number. Visit the homepage and enter your model number in the search bar — our system will show all compatible Control Boards for your specific unit. You can also call our technicians at 1-778-759-9864 for free compatibility verification.
Most Control Boards including the 121-678 ship within 1–2 business days from our warehouse. We ship across Canada and the United States, and worldwide, with tracking on every order. For urgent furnace repairs, contact us at 1-778-759-9864 for expedited shipping options.
Yes! Local pickup is available at our Coquitlam, BC location: 75 Blue Mountain St #3. Control Boards orders are usually ready within 24 hours. Call us at 1-778-759-9864 to confirm the 121-678 is in stock before visiting.
Still not sure this is the right part? Call 1-778-759-9864 and we will check your model number with you.
The model number is on the rating plate inside the furnace door.
240 more not shown. Check your own model number above.
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