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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 high-quality Air Flow Switch is an essential safety component for HVAC systems, furnaces, and industrial air handling units. Also known as an air pressure switch or air proving switch, this part monitors the differential pressure within the ventilation system to ensure the blower motor is moving sufficient air before allowing the heating cycle to engage. By verifying airflow, it prevents overheating and equipment damage, acting as a critical failsafe for your appliance. If your heating system is failing to ignite or shutting down unexpectedly, this air pressure sensor is a common replacement part to restore safe and efficient operation. Designed for precision and durability, it helps maintain optimal climate control and indoor air quality.
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
The 021-872 is a replacement part. Match your furnace model number on our site to confirm the fit. This Air Pressure Switch 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 (021-872) with your furnace model number. Visit the homepage and enter your model number in the search bar — our system will show all compatible Air Pressure Switches for your specific unit. You can also call our technicians at 1-778-759-9864 for free compatibility verification.
Most Air Pressure Switches including the 021-872 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. Air Pressure Switches orders are usually ready within 24 hours. Call us at 1-778-759-9864 to confirm the 021-872 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.
14 more not shown. Check your own model number above.
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