Last year around this time, I began writing a multi-part series on how to inspect your own house. By the time I got to part eight, it was already the end of October and the "cooling" season was well over with, so I never posted part nine. Last week's post about cheap AC tune-ups reminded me that I ought to finish this series, so here it is.
Most single family homes in Minnesota have a split system air conditioner. This consists of a big boxy-looking thing with a fan that sits outside the house, which is connected to a box that sits on top of the furnace through two refrigerant lines; one line is small and runs warm, while the other is larger, insulated, and runs cold.
Inspect the outside stuff
Start your inspection of the air conditioner by making sure that the exterior unit is clean and unobstructed. It dissipates heat by sucking in air on the sides; if it can't do that, it won't operate efficiently. This means no trellis attached to it, no ivy, no plants, etc.
Condensing coils also need to be cleaned regularly. When they're covered with dirt, dust, grass clippings, dryer lint, cottonwood seeds and other outdoor stuff, air flow can be severely hampered. Take the time to inspect all sides of the unit and clean the coils off if necessary. This can usually be done by spraying the unit down with a garden hose.
If the unit has protective grills that prevent access to the coils, the grills will need to be removed first. At that point, a little bit of dismantling is involved, and some homeowners might prefer to contact an HVAC tech to do the work.
While inspecting the exterior portion of the unit, make sure it's sitting on a level surface and that the refrigerant lines aren't being stressed. The photos below show some nice examples of air conditioners on top of soils that had settled so much that the units were tipping and the refrigerant lines were being stressed.
This is typically a simple fix, as the portion at the outside is usually lighter than most people think, and there is rarely (if ever) anything holding it in place. Older installations typically had the condenser installed on a concrete or plastic pad right on the ground, but most units installed on new homes today are mounted to the side of the house. The helps them stay cleaner longer, and it usually prevents tipping of the units. Usually.
Turn it on
Next, turn your air conditioner on by switching the thermostat to cool if it's not already there, and setting the thermostat to a temperature about five degrees cooler than the current indoor temperature. This should get the air conditioner to kick on. To be sure the system is running, look outside and make sure the fan at the condenser unit is turning.
