When your central air conditioning system is on the blink, ask yourself, "What would Sherlock Holmes do?" The great master detective of legend would observe the available clues and deduce the events that led to the crisis -- and you can do the same. Here are some common air conditioning "cases" you can help solve.
The Case of the Missing Refrigerant
Your HVAC system seemed to do an adequate job of cooling the house all through the spring, only to experience a sudden decline under the incessant broil of summer heat. The fan continues to engage as usual, but you find yourself supplementing the air from the vent with a portable fan -- and you're still hot! What's going on here?
If your AC appears to function normally except for that minor detail of cooling you off, chances are that the refrigerant level is wrong. Air conditioners need to be charged with the right amount of refrigerant (neither too much nor too little) before they can chill the air that passes through system adequately. A professional air conditioning service can check the refrigerant level and top it off as needed. If the drop-off in refrigerant is significant, ask your air conditioning repair tech to inspect the system for leaks.
The Case of the Failed Fan
Do you get absolutely no response from your HVAC fan, no matter where your park the thermostat setting? If so, then you need to turn your magnifying glass onto the electrical and electronic components that make the system run. Your thermostat's internal gadgetry may have failed after many years of yeoman service, or its sensor may have gotten dislodged from its correct position. It's also possible that the thermostat isn't receiving electricity. Check the appropriate fuse or breaker to see if it needs resetting. If these suspects all seem to have an alibi, it might be necessary to check the wiring inside the wall for damage.
What if the fan is getting both power from the wall and instructions from the thermostat, yet it still refuses to work? In this case, suspect a mechanical failure. The furnace blower motor may have a loose connection, or it may no longer spin properly. A service tech can check this component and see whether it needs just a little oil or a full-scale replacement.
The Case of the Offline Outdoor Unit
Don't forget that the typical HVAC system consists of both indoor and outdoor units. The outdoor unit performs the critical task of compressing refrigerant into a hot, high-pressure gas before sending to the condenser and evaporator (where further changes to its temperature, pressure, and state cause the air in your home to cool). If your indoor unit seems to be operational, then apply your sleuthing skills to this outdoor unit.
What are some of the clues that your compressor is guilty as charged? The first thing to check is whether it's actually running at all. If it fails to start or "stutters" to a start (a phenomenon known as hard starting), then the internal electrics may be in need of repair. If an electrical problem is causing the unit to overheat and fail, the failure will push the reset button out, so look for this clue that you may need to have some electrical work done. If the compressor tries to run for a longer period than usual without delivering much in the way of results, then your air conditioning repair service may need to replace worn mechanical parts or correct the vacuum pressure.
The Case of the Dripping Drain System
Is it raining inside your house? If you awake to mysterious puddles on your hallway floor, turn your detective's eye upward toward the overhead panel that leads to your air conditioner's evaporator. Even if the area around the rim of the panel looks dry, be aware that the drip may be so gradual that the panel is drying out between drips. A determined sleuth will want to open this panel to check for moisture -- but put a tarp down first, because a considerable amount of water may pour out when you unlatch the overhead door!
What would cause water to leak out of your HVAC system? The first thing to check for is a clogged drain line. Excess water from condensation normally drains away through this line, but a blockage can prevent this from happening, forcing the drain pan to overflow with water. Your air conditioning repair tech can squirt nitrogen into the line to unclog it. It's also possible that the drain pan has rusted out. You may even be suffering from a frozen evaporator coil that causes too much water to form. You can fix this issue by replacing the air filter or having the refrigerant level adjusted.
A sharp eye can logical approach can help you understand what's happening to your HVAC system and what might be involved in fixing it. Follow these basic guidelines, seek professional assistance as necessary, and you'll find that a cool, comfortable home is "elementary, my dear Watson!"
Share26 August 2015
Every summer, I agonized over energy bills that would shoot into the stratosphere as a result of my efforts to keep cool in the heat. Every time I turned the temperature down, my bills increased. This summer, I decided to take some of the control over my energy bill back. I installed reflective film on my windows that reduced the amount of light and heat coming into the house. I started serving more cold meals or asking my husband to barbecue outside, so that my air conditioner didn't have to compete with the hot stove, and I started doing laundry at night to reduce appliance heat in the house at peak times. I also had ceiling fans installed. So far, the difference in my bill has been tremendous. This blog is a way for me to explore other ways to reduce energy drain during the summer months.