+5% Tax • Shipping calculated at checkout.
U.S. Duties/Taxes, if applicable, may be due at time of delivery.
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 Defrost Control Board is a vital component for maintaining the efficiency and reliability of split unit HVAC systems and heat pumps. Designed to monitor and regulate the defrost cycle, this circuit board prevents frost and ice buildup on outdoor coils, ensuring optimal heat exchange during cold weather operation. Beyond its defrost functions, this versatile module supports ignition modulation, providing precise control over the heating process to enhance energy efficiency and indoor comfort. If your air conditioner or furnace is experiencing irregular cycling, failing to defrost, or showing signs of ignition failure, this replacement control board is the professional-grade solution needed to restore peak performance to your climate control system.
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 121-679 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 (121-679) 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 121-679 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 121-679 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.
9 more not shown. Check your own model number above.
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