Field Controls CAS-34U Fan in a Can Combustion Air System for Oil and Gas Appliances

The Field Controls CAS-34U "Fan in a Can" is a universal combustion air system designed to provide reliable combustion air for oil, natural gas, and LP burning appliances such as furnaces, water heaters, and boilers located in confined spaces. This versatile system mechanically draws outside air into the structure and disperses it near the combustion or intake of your appliances, ensuring adequate air for efficient combustion.

Key Features:

• Universal design compatible with both 120VAC and 24VAC control systems
• Suitable for oil appliances up to 3.5 GPH and gas appliances up to 450,000 BTU
• Electronic control with built-in pressure switch proving device that prevents burner operation without adequate airflow
• Maximum motor speed of 2600 RPM with 0.8 amp draw at 60 Hz
• Replaces discontinued CAS-3 and CAS-4 models in a single universal unit
• Can be combined with 30mV or thermopile smart valve gas water heaters using optional CK-20FV series control kit
• Expandable for multiple appliances using CAC-120 or CAC-24 control kits (one per additional appliance)
• Relieves depressurization to enable proper venting of combustion appliances

The CAS-34U complies with NFPA 54 and NFPA 31 standards for engineered combustion air systems in confined spaces. The system includes an internal pressure switch that ensures the fan reaches proper speed before allowing the burner to fire, providing enhanced safety and reliable operation. Professional installation by a licensed contractor is recommended.