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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
The Lennox Calibration Pressure Switch (0.27" WC) is a vital safety component designed for high-efficiency gas furnaces and HVAC heating systems. As an air proving switch, its primary function is to monitor the pressure differential created by the draft inducer motor, ensuring that the exhaust system is clear and functioning correctly before allowing the furnace to ignite. If the venting system is obstructed or the inducer fails to move enough air, this switch acts as a failsafe to prevent unsafe operation. Engineered for precision and reliability, this factory-calibrated pressure switch helps maintain the efficiency of your heating unit while protecting your home from potential exhaust hazards. It is a common replacement part for HVAC systems requiring a specific 0.27-inch water column sensitivity.
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 773-085 is a genuine Lennox OEM part, sourced from an authorized Lennox parts distributor. 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 (773-085) 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 773-085 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 773-085 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.
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