Minisplit Installation Accessory Checklist

Minisplit air conditioners are similar to central air conditioning or commercial split systems in that they all have an evaporator and condenser.  However, minisplits require far different support accessories for efficient, aesthetic and code-compliant installations.

Therefore, a contractor should refer to a minisplit checklist of accessories before leaving the wholesaler.  For example, wall sleeves for linesets, condensate pumps for interior wall installations, condensate traps and other items are easily forgotten when picking minisplit installation materials at the wholesaler. 

Since another trip back to the wholesaler raises job costs, the following checklist of minisplit accessories is a time-saver.

    • Wall Sleeves for Linesets — A wall sleeve and flange fitting provides a clean and smooth passageway that protects the lineset from unnecessary wear-and-tear from vibration on jagged internal wall surfaces as it passes through the structure. It also prevents ingress of water, insects and vermin into the wall cavity.
    • Condensate Trap — Gravity drained evaporators should have a special in-line waterless, freeze-resistant trap installed in the drain line on the outside wall. Without a trap, the drain line acts as a 5/8-inch hole in the system that allows outside air and odors to be drawn in as well as permitting insect ingress.

  • Drain Hose — A hose that connects to the drain pan’s 5/8-inch drain fitting is needed for condensate gravity draining. The hose should be “kink-resistant” to eliminate kinks that can lead to a build-up or clog. Typically hoses come non-insulated with variations such as UV resistance or smooth bores.  Insulated hoses must be used in non-conditioned spaces, such as attics to prevent condensation from developing on the hose surface. Hose clamps are needed to connect the hose.
  • Couplings & Adaptors — A hose coupling and adaptor (typically 5/8-inch hose to 3/4-inch pvc) may be needed to fit the hoses to the installation.
  • Condensate Pump — Minisplit installations that are mounted on a wall with no direct access for draining outdoors will need a condensate pump. There are condensate pumps made specifically for minisplits. They should be chosen based on the type of installation required and serviceability. Both surface-mounted and concealed pumps are available that fit: 1) underneath the evaporator; 2) in the elbow of the lineset cover where the lineset comes down the wall and enters from the side; 3) in the evaporator drain pan; or 4) remotely in another area. Typically capacities range from 26 feet of head at 24,000-BTU/hr to 65 feet of head at 60,000-BTU/hr.
  • Support Pad — Unlike central air conditioners, many mounting variations exist for minisplit condensers.  Pads can be concrete or lighter weight artificial materials. Condensers can also be wall-mounted with brackets, or ground-supported with slab stand or riser footings on a slab to avoid snow accumulations and yard debris. Dual-condenser projects can be streamlined with a duplex floor mount bracket. Roof mountings for upper floor installations and adjustable sloped roof brackets   are also available.   
  • Lineset Duct Cover — To finish off the lineset portion of the project with an aesthetic and professional appearance, lineset ducting, fittings and accessories should be included in any minisplit project.
  • Power  and Communication CableNo minsplit manufacturers supply a power and communication cable to link the evaporator and condenser. These cables, which are the contractor’s responsibility, can vary by gauge and number of conductors. They must also conform to manufacturers’ specifications and local electrical codes.
  • Power Disconnect Building codes require a separate wall or pedestal-mounted weather-proof disconnect switch for AC power to the outdoor condenser. A correctly sized condenser whip is needed as well.
  • Lineset — Nobody is going to forget the third most obvious part of a minisplit besides the evaporator and condenser, but it’s important to mention lineset size requirements vary by brand and model. For extra long runs, lineset couplings and an additional lineset might be needed.
  • Locking Cap for Schraeder ValveLocking caps to prevent refrigerant theft, leakage and teenage “huffing.”  The International Mechanical Code (Section 1101-10) and International Residential Code (Section M1411-6) now mandate tamper-resistant locking caps on all outdoor access ports of new air conditioning installations, including minisplits.  Local codes are expected to gradually comply with this mandate.

Finally, time is money, therefore the less return trips to the wholesaler for forgotten accessories will result in higher job profits.


Bio: Lou LaRoche is a 30-year veteran of the HVAC/R industry and currently national sales manager for Airtec Products, Fall River, Mass. Airtec Products offers the free 32-page publication, “Airtec Minisplit Accessory Catalog 2010,” which is a checklist of minisplit protection, style, form and function products along with helpful installation tips. Airtec Products carries everything the contractor needs for minisplits including Big Foot support systems, Fortress lineset protection covers, minisplit condenser mounts, drain hose, wall sleeves and other accessories, Novent locking refrigerant caps, EZ Trap condensate traps, and Aspen Pumps condensate control products. To order a free catalog, visit