8045-20 Commercial Defrost Control

8000 Series Commercial Defrost Control – Electromechanical Defrost Timer

The 8000 Series Commercial Defrost Control is a heavy-duty electromechanical defrost timer designed to provide automatic defrost control for commercial refrigerators and freezers. It can be used with several common refrigeration defrost methods, including electric heater defrost, hot-gas defrost and compressor-off-cycle defrost.

The control automatically initiates defrost cycles according to the programmed schedule. Depending on the specific 8000 Series model, defrost can be terminated by time, temperature or pressure, allowing the control to accommodate different commercial refrigeration system configurations.

Main Features:

• ❄️ Automatic Defrost Control – Provides scheduled automatic defrosting for compatible commercial refrigeration equipment.
• ⏱️ Time-Initiated Operation – Automatically starts the defrost cycle according to the selected timer settings.
• 🌡️ Multiple Termination Options – Depending on model, defrost termination can be controlled by temperature, pressure or time.
• ⚡ High-Capacity Switching – 8000 Series controls feature switch contacts rated up to 40 A and 2 HP.
• 🔄 Adjustable Defrost Frequency – Defrost initiation can be adjusted from 1 to 6 cycles per day, with a minimum of four hours between successive operations.
• ⏲️ Adjustable Defrost Duration – Backup defrost termination can be adjusted from 4 to 110 minutes in 2-minute increments.
• 🛡️ Mechanical Safety Backup – Mechanical time-driven termination provides backup protection if the primary temperature- or pressure-based termination condition is not reached.
• ⚙️ Heavy-Duty Synchronous Drive Motor – Designed for dependable timing operation in commercial refrigeration applications.
• 🔌 Positive Slider-Bar Switch Design – Helps maintain reliable electrical contact while providing a wiping action across the contact surfaces.
• 🏗️ Heavy-Duty Construction – Complete control versions are available with a durable steel enclosure designed for commercial installations.
• 🔧 Multiple Contact Arrangements – Different versions are available to suit various refrigeration control configurations.

Technical Specifications

Specifications vary by exact model. For example, Robertshaw lists 8000 Series versions for 120V AC as well as 208–240V AC, so the model number and electrical rating should always be verified before replacement.

How It Works?

During normal refrigeration operation, the timer operates according to its preset schedule. When the selected defrost time is reached, the control switches the refrigeration system into its configured defrost mode.

Depending on the equipment, this may activate electric defrost heaters, initiate a hot-gas defrost sequence or stop the compressor for off-cycle defrosting. At the end of the defrost period—or when an external temperature/pressure termination device signals completion on applicable models—the control returns the refrigeration equipment to its normal operating cycle. A mechanical timed termination provides backup protection on applicable configurations.

Typical Applications

The 8000 Series is suitable for compatible commercial refrigeration equipment such as walk-in freezers, walk-in coolers, commercial refrigerators, refrigerated display equipment, cold-storage systems, foodservice refrigeration equipment and other systems requiring scheduled automatic defrost control.