Description
McDonnell & Miller 64-HD Auto Reset Mechanical Low Water Cut Off
The Xylem-McDonnell & Miller 64-HD is a reliable, auto reset mechanical low water cut off engineered to protect hot water and steam boilers from the dangers of low water conditions. Supplied as a head mechanism only (Part Number 144400), the 64-HD is a trusted solution for boiler safety in residential and light commercial hydronic and steam heating systems.
How It Works
The 64-HD uses a proven mechanical float-based design to continuously monitor boiler water levels. When water drops below the safe operating threshold, the cut off automatically shuts down the burner to prevent dry-firing and costly boiler damage. Once water levels are restored, the unit automatically resets — eliminating the need for manual intervention and reducing service calls.
Key Features
- Auto reset operation — automatically restores burner function when safe water level returns
- Mechanical float-type design for dependable, low-maintenance performance
- Compatible with both hot water and steam boiler applications
- Maximum boiler pressure rating: 50 PSI
- Head mechanism only — mounts to existing McDonnell & Miller low water cut off body
- Part Number: 144400
- Manufactured by Xylem-McDonnell & Miller, a trusted name in boiler safety controls
Application
- Hot water heating boilers
- Steam heating boilers
- Residential and light commercial hydronic systems
Specifications
- Model: 64-HD
- Part Number: 144400
- Maximum Boiler Pressure: 50 PSI
- Reset Type: Automatic
- Mechanism: Head Only
- Compatible Applications: Hot Water and Steam Boilers
- Brand: Xylem-McDonnell & Miller
