Time Too check your Central AC Units

 

This Tip of The Month is a discussion about a central air conditioning inspection. Most central systems are split cooling types. Split systems have the air handler separated from the compressor. The air handler can be part of your furnace or an independent unit located in the basement, attic or sometimes in a closet. 

Typically begin your inspection at the exterior by examination of the outdoor unit   known as the condensing unit. First observe for any obvious damage or if the unit is out of level. There should be proper clearance around the unit and the structure as air flow is important to operate as effectively as possible. Check to ensure the electrical disconnect box is secure to the wall and that it is accessible without leaning over the unit. If the unit is running listen for unusual noises and place my hand over and above the unit to be sure it is dumping heat. If not running, activate the system if the outdoor temperature is above 65 degrees and has been for at least two days. Return to the outdoor unit to listen and observe operation.  After the unit has run for 5 minute feel the large copper pipes. One should feel hot and the other cold, if not call your HVAC contractor for service.

Inside the house inspect the ductwork where visible. You can always tell when there is an open duct when you enter the attic and it is nice and cool. Look for kinks and other defect and check for airflow in every room. You may commonly find poor connections in the ductwork.  Check along the duck works for leaking cool conditioned air into the attic, basement or crawlspace. Let the cooling system run for the entire inspection when weather permits to get a good sense of its performance.

At the air handler check for proper operation of the condensate disposal and secondary protection; which is a metal pan under the unit and a connected PVC pipe directed to the exterior of the structure? There should also have a float cutout switch connected to the pan. Rusting or corrosion is an indication of past leakage that could mean the internal pan is clogged with debris.

Units below ground level will have an electric pump connected to the condensation line. The pump will have fixable tubing connected to the pump and run to the exterior of the structure. The pump will also have a float switch. Make a visible inspection of the pump and tubing for any leaks. Of course you must check the filter. If possible see if you can see the coil inside the air handler, particularly if the filter is missing. These can clog up quickly and significantly reduce the heat transfer and air flow. If you notice clogging contact your HVAC contractor for servicing. Cooling depends upon significant air flow over the coils.

Perform a temperature differential test. Depending upon conditions in the house you might let the unit run for an hour or so if it was humid inside. The unit needs to remove the latent heat (moisture in the air) before a proper temperature drop can occur. Use a thermometer to check return temperature at the return register duct, then at a supply register duct as close to the air handler as possible as there is heat gain in the duct runs, particularly when they are in a hot attic. There should be at least a 20 degree difference the supply and return register.

Once you am satisfied the unit is operating properly, or you have identified performance issues, return the thermostat to its original position. Remember cooling units require annual service and we recommend doing so.

Have a cool summer!!!   DM HOME INSPECTIONS.

 

 

 

 

 

 

 

 

 

 

 

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               Remember DM HOME INSPECTIONS for your next Home.

908-247-4524 or 201-694-1630