3" HIGH LIMIT SWITCH L240-40F 3 High Limit Control Switches
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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
Ensure the safety and efficiency of your heating system with this professional-grade 3-inch high limit control switch. As a vital safety component for residential furnaces and HVAC units, this sensor monitors internal temperatures to prevent the appliance from overheating. The switch is designed to automatically interrupt the heating cycle if the temperature exceeds a specific safety threshold, protecting your equipment from potential damage and ensuring a safe operating environment. Perfect for HVAC repairs and preventative maintenance, this thermal limit control is built for reliability and long-lasting performance in forced-air heating systems. Its standard 3-inch profile allows for precise heat detection within the plenum, making it an essential replacement part for maintaining optimal furnace functionality and home safety.
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 543-235 is a genuine OEM, or a factory replacement manufacturer approved part. We source all 3 Limit Switches from authorized distributors to ensure exact-fit compatibility. 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 (543-235) 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 543-235 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 543-235 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.
175 more not shown. Check your own model number above.
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