The evap coil in my mobile home's closeted air handler is positioned at the main top, with the blower and furnace underneath. A few inches above the coil's air filter at the top of the air handler cabinet, an insulated, hollow "tube" of approximately 5" i

In your mobile home's air handler setup, it sounds like you have a configuration commonly used in HVAC systems where the evaporator coil (evap coil) is situated at the top of the unit and the blower and furnace are positioned below it. The insulated, hollow "tube" hanging down likely serves an important purpose in the overall airflow direction and system efficiency. 1. **Air Flow Direction**: In this configuration, the blower typically pulls air up through the air filter located just above the coil. The air filter cleans the air before it flows through the evaporator coil. After passing through the coil, where it is cooled (in the case of air conditioning), the air is then pushed down through the ductwork to the living spaces of the home. 2. **The Insulated Tube**: The "tube" you described could be part of a condensation drain system. In evaporator coils, moisture is collected during the cooling process. This tube may serve to transport the condensate (water) away from the coil and down to a drain or a condensate pump. It’s crucial for preventing water damage and ensuring that the coil operates efficiently. 3. **Ducting Considerations**: The insulated tube may also represent a portion of the ducting system that connects the air handler to the rest of the home. Insulation is important for reducing energy loss and maintaining the temperature of the air being delivered. Overall, this setup suggests that the air handler is designed for efficient airflow from the top down, where the air is filtered, conditioned, and then distributed throughout the mobile home. Make sure that the condensation drainage system functions properly to prevent water accumulation and potential issues. If you have further specific questions about maintenance or adjustments, consider consulting a professional HVAC technician. Update (2025-08-25): From your description, it sounds like your mobile home's air handler is set up with a vertical air flow orientation. Here's a breakdown of the components and their roles in this type of configuration: 1. **Evaporator Coil on Top**: The evaporator coil being positioned at the top of the air handler indicates that the airflow is designed to move from the top down. As air is drawn in through the filter located above the coil, it passes over the evaporator coil where it is cooled before being sent into the living space. 2. **Blower and Furnace Below**: The blower and furnace are located beneath the evaporator coil, which is common in a vertical configuration. In this setup, the blower pulls air from the space above, drawing it down through the coil and then pushing it back out either through ducts or vents. 3. **Insulated Hollow "Tube"**: The "tube" you mentioned, with an interior diameter of approximately 5 inches, is likely a return duct or a section of plenum that connects the air handler to the return air system. This structure allows the system to recirculate air from the living space back to the air handler. **Flow Orientation**: Given this configuration, the airflow is typically as follows: - **Incoming Air**: Air is pulled into the air handler from the living space through the insulated "tube" or return duct. - **Cooling Process**: The air moves down through the air filter (which removes particles and dust) and then passes over the evaporator coil to be cooled. - **Outgoing Air**: The blower then pushes the cooled air back out into the home through the supply ducts or vents. Overall, you have a top-down flow orientation in your air handler, which is designed to efficiently cool and circulate air through your mobile home.