Questions & Answers
Questions & Answers
QUESTIONS & ANSWERS
Sizing and Installation of a Mini Split
Mini-Split system installation falls within the direct category of air conditioning installation. DuctlessAire systems are NOT designed to be “DIY”. Although much easier to install than a conventional HVAC system, proper installation of a mini split DOES require specialized tools such as, but not limited to
- Nitrogen tank and regulator
- Digital micron gauge
- Digital scale
- 45° Flare tool
- Torque wrenches (for flare nut connections)
- Vacuum pump
- Refrigerant manifold gauges
- Refrigerant recovery tank
- Refrigerant recovery machine
- R410A Mini Split Adapter (1/4″ SAE Male x 5/16″ SAE (1/2″-20 UNF) Female)
Most Mini-Split manufacturers have both minimum and maximum length requirements and most outdoor units are shipped with a refrigerant charge. Refrigerant lines that are too long will compromise a system’s performance. Lines that are too short may result in premature compressor failure!
Our DuctlessAire mini split systems include a 25’ length line set. The minimum that it can be cut down to is 10’. If cut down it must be re-flared. If you need longer than 25’ you may purchase a run up to 50’ from a HVAC parts house. Refrigerant lines cannot be spliced together it should be one continuous run. Any adjustment to the 25’ length may require an adjustment to the refrigerant charge.
Condensate piping also known as a drain line is extremely important, not only to the unit but also your home. Wall-mounted units require a condensate drain line. It is important that you determine where the condensate drain line will go BEFORE installing the indoor unit. The condensate drain line typically requires a downward slope in the range of ¼ inch per foot, without any crimps in the line. One frequent source of callbacks is condensate (water) leakage. Water running down your wall can be an indication of an improperly installed drain line and/or your unit needing maintenance performed with the drain line blown out. It is also recommended that the condensate line be insulated due to sweating in the cooling season.
Before an indoor unit is permanently installed, clarify and verify exactly where the unit is to be located. Too often, a location the contractor has in mind may vary from what the homeowner had expected. Refer to the manufacturers installation literature to ensure that the air distribution will suffice but avoid installing the unit where it blows air directly on the people in the room.
Stated clearances to the front, sides, and rear MUST BE ADHERED TO in order to provide adequate airflow through the outdoor unit. If need be, be creative in outdoor unit placement to ensure clearances are met is a wise investment as the minimum unit clearances must never be compromised. A poorly located outdoor unit can and will inhibit airflow, reduce system capacity, may result in nuisance shut down and even lead to premature equipment failure.
While most mini split systems have similar operating characteristics, it is IMPERATIVE that the installation instructions specific to the equipment you’re installing, are obtained prior to installation and read through thoroughly. Often, an installation manual is as much of a legal document as it is a technical reference, thus all cautions and warnings must be followed for your personal safety.
Bigger is NOT always better! Too often, in the HVAC industry, larger is interpreted as more effective and provides a higher degree of comfort. The truth of the matter is oversized equipment can result in a shortened equipment lifespan with erratic temperature and humidity control of the conditioned space. A comprehensive load calculation is the foundation of all mini-split systems success.