PRESSURE SWITCH 0.70" WC MOSTLY FOR BURNHAM BOILER Air Pressure Switch, Air Proving
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U.S. Duties/Taxes, if applicable, may be due at time of delivery.
Pickup available at 75 Blue Mountain St #3
Usually ready in 24 hours
Not sure this fits your furnace? Call us — we're happy to help
This premium air pressure switch is a vital safety component for residential and commercial heating systems. Functioning as an air proving switch, it monitors the vacuum pressure created by the draft inducer motor to ensure proper airflow before the ignition sequence begins. By verifying that the exhaust system is clear and the fan is operating at the correct speed, this pressure switch prevents unsafe operation and promotes efficient fuel combustion. Whether you are troubleshooting a boiler that won't ignite or performing routine furnace maintenance, this reliable sensing switch is designed to restore safety and performance to your HVAC equipment.
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 773-421 is a genuine OEM, or a factory replacement manufacturer approved part. We source all Air Pressure Switches from authorized distributors to ensure exact-fit compatibility. 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 (773-421) 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 773-421 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 773-421 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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