This single question posed to AC contractors can reveal a lot on how the company performs their installations. You can trust and like your sales rep but if they don’t know or you get a blank stare as a initial response, you’re better off finding a contractor who is a little less polished but knows their installation crews. In Phoenix your air conditioner replacement is the most important day of its life and you want to carefully screen any AC contractor that gives you replacement costs.
Experienced air conditioning contractors are good because they know where the hiccups occur during an air conditioner install and how to avoid them and they know what the most common call backs are and how to avoid them. Most of the time doing the right thing requires a little extra effort on their part during the AC install. For most AC contractors this is not the standard way of doing their installs and just like learning how to swing a golf club the correct way verses the easy way, it takes them out of their comfort zone and most would rather just skip doing the extra effort verses spending a little more time, effort and materials to do it right.
You definitely want to hear an air conditioning contractor tell you they do the following:
1. Charge the system with the correct amount of refrigerant after installation. This is not factory settings as every system comes with refrigerant already charged it. Many contractors just leave the factory charge and do not bother adding any more or measuring to find out how much more is needed and this is a big problem. If the distance from your outside condenser to the inside air handler is more than 15 feet, your AC contractor should be adding more refrigerant as the manufacturers only add enough refrigerant for 15 feet of refrigerant line.
2. Size the unit according to what your home needs, not based on the square footage of the house alone. This requires a Manual J calculation on the house so you should see your contractor measuring your windows and actually going in your attic to measure the insulation.
3. For package roof units, you want a side by side elbow, not a down draft and not a over-under aka twist elbow. This is a major no no that most AC contractors are guilty of not following. Down draft and over-under elbows are cheaper and easier to install and require less labor and materials but are NOT best for your energy bills, comfort and the life of your system. If your AC contractor is really stuck in their ways or really lazy, they will make up excuses on why down draft and over-under elbows are OK to install, they may even believe what they are saying is true but hold firm in your affirmation that you want a side by side elbow.
4. They install supply and return plenums
A plenum is a transition between the ductwork and the unit. If your furnace or air handler is in the attic like most are in Phoenix, the plenum is likely a sheet metal box that has flex duct connecting into it and the other side is attached to the furnace. If your furnace or air handler is in the garage or closet, the return plenum is the framed box that it sits on and the supply plenum is the sheet metal on top. Plenums are important for proper airflow, allowing the unit to breath and mix air in the box before it hits the evaporator coils. They are not always included in the cost of an AC but should be. It is extra work to install them but every home should have them.