Full Installation of Mini Split Ductless Unit, Step by Step!

Craig Migliacio from AEC Service Tech introduces the video by discussing the full installation process of a Cooper and Hunter inverter type heat pump system, also known as a ductless system. He outlines the main components involved, including the indoor head unit, outdoor heat pump, copper tubing (line set), and communication wire. Craig also mentions the pre-installed live voltage electricity and explains the step-by-step installation process, emphasizing the use of various tools and supplies, which he plans to detail throughout the video.

Craig demonstrates the process of mounting the indoor head unit, including the use of a template for layout, determining the location for electrical lines and tubing, and identifying wall studs. He explains the importance of correctly positioning the unit and ensuring that the holes for the electrical line and tubing align with the wall's structure. Craig also shows how to use a metal plate as a template for drilling holes and securing the unit with screws.

In this section, Craig focuses on preparing the wall for the copper tubing and electrical lines. He discusses the use of a probe to ensure the correct angle for drilling holes, the importance of creating a sealed cavity for the tubing, and the process of drilling the hole with the appropriate precautions. Craig also explains how to temporarily insert PVC into the wall to create a guide for the tubing and ensure a snug fit.

Craig measures and cuts the PVC guide to the correct length and angle to fit the wall's penetration for the tubing and electrical lines. He emphasizes the importance of ensuring a snug fit and a proper seal to prevent any heat loss or insect entry. The process involves tracing the outline of the PVC on the wall, cutting the excess, and smoothing the edges to avoid any damage during the tubing installation.

Craig explains the process of connecting the electrical components for the indoor head unit, including the use of a seal tight connector and the importance of protecting the tray cable with electrical conduit when exposed. He details the process of threading the wire through the seal tight and making the necessary electrical connections, ensuring that the color scheme is consistent with the wiring diagram provided by the manufacturer.

Craig demonstrates how to straighten the copper tubing and remount it in place, ensuring that there is enough wire to reach the indoor air handler. He discusses the importance of avoiding kinks and applying pressure correctly when bending the tubing. The process involves twisting sections of the tubing, reconnecting the electrical compartment, and taping all components together to fit through the two-inch PVC pipe.

Craig focuses on the process of flaring and connecting the copper tubing for the vapor and liquid lines. He explains the use of a torque wrench, the importance of applying nylog or refrigerant oil to the flare face, and the specific torque values required for each connection. The process involves cutting the outer jacket, using a tubing cutter, and ensuring that the flares are properly formed and tightened according to the manufacturer's instructions.

Craig performs a nitrogen pressure test to check for leaks in the system. He explains the use of a compound manifold gauge set, the importance of monitoring the pressure over time, and the use of a bubble leak detector to check for leaks at the flare connections. The process involves pressurizing the system to 300 psi, allowing the pressure to sit for a specified time, and observing any changes in pressure or the formation of bubbles to indicate leaks.

Craig sets up the vacuum pump and explains the process of conducting a vacuum test to remove moisture, air, and nitrogen from the system. He details the use of valve core removal tools, the importance of achieving a vacuum level below 500 microns, and the standing vacuum test to ensure that the vacuum holds without any pressure loss. The process involves attaching the vacuum gauge, evacuating the system, and monitoring the vacuum level during a 10-minute test period.

Craig discusses the process of wiring the outdoor disconnect and communication lines. He explains the use of crimp connectors, the importance of using the correct wire gauge, and the process of connecting the ground, L1, and L2 wires to the disconnect box. The process involves stripping and crimping wires, attaching the connectors, and ensuring that the power is off before making any connections.

Craig explains the process of sealing the penetration through the wall and mounting the drain line. He details the use of a piece of PVC, a downspout, and an exterior sealant to ensure a waterproof seal. The process involves cutting the downspout to the correct length, attaching it to the PVC clamps, and ensuring that the drain line is properly sealed and secured.

Craig turns on the system and checks its operation, including the return and supply temperatures, delta T, and superheat. He explains the importance of achieving a good delta T and maintaining a low superheat for efficient system operation. The process involves observing the system's performance, confirming the correct superheat value, and ensuring that the system is running quietly and effectively.