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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 3-inch high limit switch is a critical safety component designed for forced-air heating systems and residential furnaces. Functioning as a thermal cutout, this switch monitors the internal temperature of the heat exchanger or plenum. If the system exceeds a safe operating temperature, the switch automatically breaks the electrical circuit to prevent overheating and potential damage to the appliance. Once the temperature cools to a safe level, the internal bimetal disc resets, allowing the system to resume normal operation. Essential for DIY furnace repair and HVAC maintenance, this high-limit control ensures your heating equipment operates within manufacturer safety parameters, protecting your home from fire hazards and mechanical failure caused by restricted airflow or component malfunction.
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 543-003 is a replacement part. Match your furnace model number on our site to confirm the fit. This 3 Limit 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 (543-003) with your furnace model number. Visit the homepage and enter your model number in the search bar — our system will show all compatible 3 Limit Switches for your specific unit. You can also call our technicians at 1-778-759-9864 for free compatibility verification.
Most 3 Limit Switches including the 543-003 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. 3 Limit Switches orders are usually ready within 24 hours. Call us at 1-778-759-9864 to confirm the 543-003 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.
70 more not shown. Check your own model number above.
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