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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 premium Lennox pressure switch is a vital safety component for residential and commercial HVAC systems. As a single-port air proving switch, it plays a crucial role in the furnace ignition sequence by monitoring the pressure differential created by the draft inducer motor. With a precision-calibrated 0.43" WC (Water Column) set point, this SPST (Single Pole Single Throw) switch ensures that flue gases are being properly vented before the burner is allowed to ignite. If your heating system is experiencing ignition failure or displaying pressure switch error codes, this replacement part is essential for restoring safe and efficient furnace operation. Designed for durability and precision, it serves as a reliable solution for heating system repairs and routine maintenance.
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 773-335 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 (773-335) 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 773-335 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 773-335 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.
5 more not shown. Check your own model number above.
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