Lochinvar & A.O. Smith 100110973 Switch
The Lochinvar & A. O. Smith 100110973 Blocked Flue Switch is a critical safety component designed for high-efficiency boilers and commercial water heaters. As a veteran technician knows, this negative pressure switch (often referred to as a spill switch) is engineered to sense obstructions in the venting system, protecting the heat exchanger from hazardous flue gas recirculation. When the integrated sensor detects a lack of proper draft or a blocked vent condition, it breaks the 24V control circuit, immediately initiating a system lockout to prevent carbon monoxide leakage or equipment damage.
This OEM replacement part is built for precise horizontal or vertical mounting and is widely compatible with Lochinvar Knight and A. O. Smith Cyclone series units. For optimal performance, ensure all silicone sensing tubing is clear of moisture or debris during installation. Replacing a failed 100110973 switch is essential when troubleshooting persistent blocked flue fault codes or proving issues where the blower is operational but the ignition sequence is interrupted.
Key Benefits- Ensures safe venting operation by monitoring exhaust pressure and preventing dangerous backdrafts.
- Direct OEM replacement for Lochinvar 100110973, maintaining the original safety certifications of the appliance.
- Highly sensitive diaphragm resists thermal fatigue, providing reliable switching in demanding HVACR environments.
- Universal compatibility across multiple commercial boiler and water heater platforms simplifies truck stock requirements.
What causes a blocked flue switch to trip?
Common culprits include physical obstructions like bird nests, heavy snow at the termination, or condensation buildup in the pressure sensor tubes. Excessive vent lengths beyond the manufacturer’s specification can also cause nuisance tripping.
How do I test the 100110973 switch?
Using a manometer and a multimeter, verify that the switch closes at the specific inches of water column (W.C.) rating stamped on the housing. If the switch remains open while the blower is at full RPM and the vent is clear, the diaphragm may be ruptured.
Can I bypass this switch during an emergency?
No. This is a primary safety limit. Bypassing a blocked flue switch can lead to deadly carbon monoxide levels. Always replace a faulty switch immediately to restore safe operation.
This item is not eligible for free shipping.
Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
Original: $56.97
-65%$56.97
$19.94Product Information
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Description
The Lochinvar & A. O. Smith 100110973 Blocked Flue Switch is a critical safety component designed for high-efficiency boilers and commercial water heaters. As a veteran technician knows, this negative pressure switch (often referred to as a spill switch) is engineered to sense obstructions in the venting system, protecting the heat exchanger from hazardous flue gas recirculation. When the integrated sensor detects a lack of proper draft or a blocked vent condition, it breaks the 24V control circuit, immediately initiating a system lockout to prevent carbon monoxide leakage or equipment damage.
This OEM replacement part is built for precise horizontal or vertical mounting and is widely compatible with Lochinvar Knight and A. O. Smith Cyclone series units. For optimal performance, ensure all silicone sensing tubing is clear of moisture or debris during installation. Replacing a failed 100110973 switch is essential when troubleshooting persistent blocked flue fault codes or proving issues where the blower is operational but the ignition sequence is interrupted.
Key Benefits- Ensures safe venting operation by monitoring exhaust pressure and preventing dangerous backdrafts.
- Direct OEM replacement for Lochinvar 100110973, maintaining the original safety certifications of the appliance.
- Highly sensitive diaphragm resists thermal fatigue, providing reliable switching in demanding HVACR environments.
- Universal compatibility across multiple commercial boiler and water heater platforms simplifies truck stock requirements.
What causes a blocked flue switch to trip?
Common culprits include physical obstructions like bird nests, heavy snow at the termination, or condensation buildup in the pressure sensor tubes. Excessive vent lengths beyond the manufacturer’s specification can also cause nuisance tripping.
How do I test the 100110973 switch?
Using a manometer and a multimeter, verify that the switch closes at the specific inches of water column (W.C.) rating stamped on the housing. If the switch remains open while the blower is at full RPM and the vent is clear, the diaphragm may be ruptured.
Can I bypass this switch during an emergency?
No. This is a primary safety limit. Bypassing a blocked flue switch can lead to deadly carbon monoxide levels. Always replace a faulty switch immediately to restore safe operation.
This item is not eligible for free shipping.
Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.
