Before you start any kind of repair on any kind of appliance it is important to do so safely! All air-conditioning equipment uses electricity, so it is vital that you turn off the power before attempting any kind of repair. Do this by going to the breaker panel and turning off the appropriate breaker. The air-conditioner works in conjunction with the furnace. The power to the furnace will also need to be turned off before attempting repairs and it should have a separate breaker. Air-conditioner equipment have fans, belts and mechanical items that can turn on suddenly without warning. Obtain your manuals and read them. Heed their safely warnings.
A/C Unit
Air conditioning condensing unit that sits outside, has a fan on top, usually blows out hot air
Evaporator
Heat exchanger coil that is located inside the duct-work, usually just above the furnace
My top eight list before calling in the repairman.
Check to make sure that your air-conditioner has the power turned on.
Now this may seem a little obvious but it happens more often than you would think. The power to your furnace and A/C unit must both be on. Check the breaker box for both. Furnace is typically a single pole breaker(one switch), and the A/C unit usually is a 2 pole breaker(two switches tied together). Also the furnace and A/C unit usually have additional switches. The furnace usually has its additional switch inside the house, in the stairwell or near the furnace. The switch looks like a typical light switch and is located high on the wall to prevent accidentally turning it off. The additional switch for the A/C unit is usually located within arms reach of the A/C unit itself. Check the thermostat to make sure that it is calling for cooling.
Make sure the thermostat is set to cool and is set to an appropriate temperature (21C or 72F). If you have a programmable thermostat make sure the time is set correctly and that the programmed temperatures and periods are correct. Don't set your thermostat below 20C or 70F.
If you do you run the risk of freezing your evaporator. When your evaporator freezes, your air-conditioning doesn't work very well, you get very little air flow from you vents and sometimes you can see frost on exposed refrigerant piping. After you freeze your evaporator, you need to turn the A/C unit off. Do this by turning the system Heat/Off/Cool switch to "Off" and the fan On/Auto switch to "On" for a couple of hours. Then set system switch back to cool and set thermostat to proper setting. Make sure the furnace filter is clean.
The A/C unit relies on the furnace to provide a certain amount of air flow to distribute cold air throughout the house. If the filter is dirty it will block this air and cause the evaporator to freeze. Go to step three. Make sure the furnace fan belt is tight and new.
Hopefully you have a direct drive fan motor and you don't have to worry about this issue. Otherwise, a sloppy belt will cause your furnace to have a decreased amount of air flow and could cause your evaporator to freeze. Go to step three. Clean the A/C unit.
This is the number 1 maintenance issue with air-conditioning systems. Performing this step will increase system capacity, protect the compressor, and reduce electrical consumption. The A/C unit has a coil on the outside that gets very dirty. The coil is like a radiator coil in a car. Take a hose and wash this coil out. Make sure the water goes right through the coil to get all of the dirt out. Inspect the main blower fan for dirt and if dirty pull out and clean.
The main blower is located in the bottom compartment of the furnace. It can be removed usually by removing a few screws or bolts. That should release the entire blower assembly. The electrical from the motor will also need to be disconnected. Sometimes there can be other electrical components obstructing your way to removing the blower assembly, making this a more advanced problem. After removing the blower assembly, take it out to the back yard and hose out the squirrel cage fan wheel. You can use compressed air if you don't have water. Then reinstall. If your fan was really dirty your evaporator could be frozen. Go to step three.Clean out the condensate drain for the evaporator.
If your condensate drain gets plugged then you usually find lots of water leaking out of your duct-work and around your furnace. Find the evaporator just above the furnace in the duct-work. You won't actually be able to see the evaporator but you should see the pipes coming out of the duct-work from the evaporator. There should be 3 pipes altogether. Two of the pipes are located close together up higher. Of these two pipes one is smaller and one is larger.
The large pipe is usually covered in a black âspongyâ material. One other pipe is located about a foot below. This is the pipe you want to work with. This pipe is the condensate drain pipe and if you follow it, should go down to a floor drain somewhere. Usually it is flexible. Find the end of it that has been shoved into the floor drain. Pull it out and use a shop vac to suck the drain line clean. You will only need to do this for about 30 seconds. Don't forget to put the drain line back into the floor drain.
Most of the above problems revolve around dirty components and the ability to understand and use the thermostat. If you can take care of these problems yourself then you are well on you way to a cool summer. If you have any other problems beyond that you can be well assured that your only choice will be to call in the professionals.
