Resideo L4006A2007 Aquastat High Low Limit Controller

Product Description

The RESIDEO L4006A2007 is an aquastat high/low limit controller designed for hydronic heating systems. It breaks the circuit on a rise in temperature and operates across a sensing range of 100 to 240 degrees F with an adjustable differential of 5 to 30 degrees F. The controller fits insulation-less wells with a 3-inch immersion element, making it suitable for boiler loop control applications. Licensed HVAC and plumbing technicians install this type of controller to protect boilers and hot water heating equipment from over-temperature or under-temperature conditions.

This aquastat controller is used in residential and light commercial hydronic heating systems. It is typically installed on a boiler or supply line to monitor water temperature and cycle the burner or circulator pump based on setpoint and differential settings. The adjustable differential allows the technician to fine-tune the control band to match system demand. It is appropriate for installations where a dedicated immersion well is not present, as it is rated for insulation-less well mounting.

Key Features

• Temperature sensing range of 100 to 240 degrees F for broad hydronic system coverage
• Adjustable differential of 5 to 30 degrees F for precise control band tuning
• Breaks on rise configuration for high or low limit protection
• 3-inch immersion element fits insulation-less well installations
• Single-unit packaging for straightforward job-site procurement

Compatibility

Designed as an OEM-style replacement or new-installation aquastat controller for residential and light commercial hydronic heating and boiler systems requiring high or low limit temperature control.

Installation Notes

Installation should be performed by a licensed HVAC technician or plumber. Shut off power to the boiler and allow system water to cool before removing or installing the aquastat. Follow all applicable local mechanical and electrical codes, including NEC requirements for low-voltage control wiring. Do not overtighten the immersion element into the well, and verify the sensing element is fully seated before restoring power.