1-     Turn the power off to both your furnace and air conditioner. Some of the steps we will be discussing are dangerous if power is present. For the furnace and the air conditioner there should be separate breakers in your electrical panel that you will shut off.   

2-     Remove the front door of the furnace and vacuum out the enclosure, as well as clean out any debris that may be in the fan housing, then replace the filter with a new one.

3-     Give the fan blade a spin and listen for a rumbling sound and check if the fan is spinning freely. This is an indication that you may have a possible bearing problem. If oil ports are present on the motor or bearings, put a few drops of non detergent oil in them. Then close up the furnace and head outside.

Note: If you think there is a bearing problem it should be looked after soon. If you want to try to change the motor yourself and need some help, try to describe problem and post your question. See step 10. If you do not want to attempt the work. Call a qualified technician.

4-    (Remember, Power off) Remove the access door from the outdoor unit  and clean any debris from it as well as those cobwebs and nests that tend to accumulate around the electrical relays, also note any damaged wiring.

5-     Apply a cleaning agent like a medium strength household cleaner (using a spray bottle), to the outdoor coil, then wash it off with your garden hose.  When cleaning the coil make sure to use enough water pressure that you can see the water spray completely through the coil but not enough pressure that you may damage it.

6-      Just like with your furnace give the fan blade a spin and make sure it sounds smooth, also check for any hair line cracks in the blade or any play (Looseness) in the pop rivets holding it together. If an oil port is present on the motor add a few drops of non detergent  oil into them. When that is all complete, close the unit up and restore the power to it as well as the furnace.

7-    To perform this step you should try to wait until the outside air temperature in the mid to high 70’s (21 deg C). This will allow the system to be running near its peak operating pressure.

 Ok let’s turn it on.

While the unit is running, have a walk around the furnace inside as well as the air conditioner outside. Listen for sounds you may not have noticed before. When you’re satisfied that everything seems ok, let it run for 15 minutes.

If for some reason you do hear any unusual noises, or problems you may encounter, try to describe problem and post your question. See step 10.

8-     While were letting it run, have a look at the vents in the whole house and make sure all they are all open. We have a tendency to shut off some vents to try to get the air to the upper levels in our home. Too much restriction in the ductwork is hard on the air conditioner. Closing a few vents is ok but, it’s good to start the year off clean. I recommend reducing the amount of air into the basement, but nowhere else. If you are having problems with cooling the 2^nd  floor, it’s more than likely the problem is with the location of the return air grill on the 2^nd  floor and not the amount of cool air entering the space. If you need more advice on air balancing. See step 10.

9-     Head outside and let’s see how the unit is operating. The first thing you should notice is that the air blowing off the unit should be warm. Next, look for the 2 copper lines exiting the unit, one will be small, the other larger line, is most likely covered in a black insulation. 

This small line is called the liquid line. The temperature of this line should be neutral to warm to the touch. The larger one may need a bit of insulation removed to check it; this one should be cool to cold, not cold like an ice cube, but cool enough that you feel it. Normally its temperature is in the 50˚-55˚(10-12 deg C) area. If you are unsure and need some advice See step 10.

While you are checking temperatures, one other thing you can check is the temperature difference across the furnace. Meaning, the difference between the incoming and out going air.

Back into the house we go

Place a thermometer in or at the return air grill and take a temperature reading, then do the same thing a at the supply air grill. Subtract the difference in your temperature readings. This number should be in the area of 15˚ (9.5°C) if is not See step 10.

 That’s it your all done.

10 - If you require further information like a more detailed explanation of any of the above steps. You can register as a user by clicking at this link http://www.hvacmechanic.com/forums/forum-register.htm then you can post us a message in our forums at http://www.hvacmechanic.com/forums/forums.htm. This is a free service. Should you have any questions at any time about any part of your air conditioning, furnace, ventilation, humidification, or you need advice on some work you had quoted by a contractor. Post questions in the forums

Step 10