Lochinvar & A.O. Smith 100074203 Drain Port

The Lochinvar & A.O. Smith 100074203 Drain Port is a critical OEM component engineered for high-efficiency condensate management in residential and commercial heating systems. Designed specifically for compatibility with Lochinvar Knight boilers and select A.O. Smith water heaters, this 1/2-inch PVC port facilitates the controlled removal of acidic byproduct from the secondary heat exchanger. As an authentic EKH23 replacement part, it features precision-molded threads for a leak-free NPT connection, preventing the internal pooling that leads to heat exchanger corrosion and premature pressure switch trips. This factory-authorized condensate drain includes integrated venting ports to maintain atmospheric pressure within the drain line, ensuring consistent flow and preventing airlocks that can cause system lockouts. For technicians performing annual maintenance or emergency repairs, utilizing this OEM boiler replacement part guarantees that the drainage assembly meets the manufacturer's exact hydraulic specifications.

• Direct Fit Compatibility: Specifically designed for Lochinvar Knight and A.O. Smith commercial water heaters, ensuring a secure match with part numbers 100074203 and EKH23.
• Corrosion Resistance: High-grade PVC construction withstands the corrosive nature of wastewater produced during the combustion process.
• System Protection: Optimizes condensate water flow to prevent overflow into the burner assembly and sensitive electronic components.
• Integrated Venting: Features a specialized port design that balances pressure, allowing for reliable gravity drainage without the risk of siphoning.

What models are compatible with this drain port?
This component is primarily used in the Lochinvar Knight boiler series (including KBN and WHN models) and various A.O. Smith high-efficiency units. It is the direct replacement for legacy part number EKH23.

Are the holes above the threads supposed to be there?
Yes. Those are engineered venting ports designed to prevent air pressure from backing up the condensate line. They must remain unobstructed and should never be sealed.

Does this include the O-ring or gasket?
This SKU typically refers to the K Port Drain Condensate fitting itself. It is recommended to inspect your existing seals and O-rings during installation to ensure a complete moisture-tight seal.

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.