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20-point central a/c

1. Check The Refrigerant Lines


The refrigerant line runs from the outdoor condenser unit to the indoor evaporator coil. That part of the refrigerant line, which lies outside, often gets damaged from something as small as a ricocheting stone. The damage can cause the line to develop a crack or a hole from which the refrigerant may leak. If the leak is too much, it will impact the cooling in your home. On inspection, if any such cracks are discovered, they are sealed.


2. Examine the Insulation Of Refrigerant Line


If the refrigerant line does not have proper insulation, it causes condensation. If the condensation is on the outside, that’s still manageable. Still, if the same thing happens indoors, there can be water damage. Most importantly, any dampness indoors is an open invitation for mold to grow. Therefore, the insulation of the refrigerant line needs to be checked thoroughly.


3. Check The Refrigerant Level


In the first checkpoint, we spoke about cracks or holes appearing in the refrigerant line from which the coolant may leak. So another important checkpoint is the present level of the refrigerant. If the level has dropped, it needs to be replenished.


4. Check The Evaporator Coil


Any dirt or corrosion on the evaporator coils has a direct bearing on the cooling capability of the AC. So, the cleanliness and overall condition of the evaporator coils need due attention. The technician will ensure that the coils are clean and take steps to minimize the effects of corrosion.


5. Inspect The Condenser Coil


The coils in the outdoor condenser unit are highly susceptible to collecting dirt. It is primarily because of their location which they have to bear the brunt of nature. In spite of their location, the cleanliness of these coils is also paramount. Thanks to the fins behind which these coils reside, they don’t get dirty quickly.


6. Examine The Air Filters


Though the air filters should be changed monthly, still as a part of the tune-up, the technician will inspect them. It is more to make sure that you are replacing them with the right kind and that, too, timely.


7. Inspect The Blower Fan And Motor


The blower fan pulls the air in through the air filters and pushes the cool air indoors. If the fan blades are dirty or if its motor is faulty, the fan will not work appropriately. Upon inspection, the technician can assess the cleanliness of the blades and also the condition of the motor.


8. Assess The Capacitors


Usually, an AC has around three capacitors. Even if one fails, your unit will malfunction. At the time of tune-up, these capacitors are given a thorough once over to determine whether they have any juice left. If not, they are replaced before the AC is compromised.


9. Gauge The Overflow Safety Switch


There is an overflow safety switch in the air conditioner. It shuts down the unit if the water is not draining out properly. If the safety switch works as it should, you will not face the problem of any leak originating from the AC. The technician tests the overflow safety switch during maintenance.


10. Inspect The Ducts For Air Leak


Old ducts may develop leaks due to the deterioration of the material. Even new ones may develop cracks due to critter menace or man-handling. A leaky duct makes it difficult for the AC to cool your home sufficiently due to the loss of cool air and the mixing of warm air. Catching such a problem at the time of tune-up is critical to the health of your energy bills.


11. Check The Drip Tray And Drain Line


Even with the overflow safety switch working properly, drips may still appear. It may happen because the drip pan has holes or cracks in it. Such an occurrence is not unheard of. It is usually found in old AC’s where the drip tray falls prey to corrosion. At the same time, the drain line is also given a thorough test to ensure that there are no blockages. If any are found, they are removed.


12. Check The Thermostat


The thermostat is the remote of the air conditioner. There is no way to turn on the AC if the thermostat is dead or has developed some fault. Therefore the calibration of the thermostat, life in its battery, and wire connections are all inspected.


13. Inspect The Disconnect Box 


Also known as the safety shutoff box; it cuts the power supply to the AC. It is a safety measure that ensures your AC will not fry in case of any unprecedented incident like a power surge or overheating of equipment. All connections in it need to be tight and secure, none hanging loose. According to the mechanical HVAC code, it should be sealed with transparent silicone on the top as well as the sides.


14. Examine The Platform On Which the AC Rests


The AC unit needs to rest on a level surface. Therefore, its platform needs to be checked for any damage that makes the unit unbalanced. The imbalance may cause the unit’s fan blade to warp and ultimately damage the motor shaft.


15. Measure The Amperage Of The AC


The amperage is a way to gauge the condition of the various parts of the AC. The thumb rule is that the reading should always be a little below the numbers printed on that components sticker. If it leans towards the maximum or is over the recommended reading, the component is working way too hard, which can cause its overheating.


16. Calculate The Temperature Split


The actual temperature that is inside the house as against that which blows from the vents is known as the temperature split. Ideally, it should be 15 degrees on average. If the split is less than that, it is a sign of trouble. It could mean that your AC is small in size, or it has come leak or blockage. Only the technician can gauge the split and assess the problem.


17. Examine The Contactor


The contactor gets signals from the thermostat about turning the AC on and off.  A faulty contactor with bad connections or burnt wires disrupts this communication due to which the AC may not turn on at all. Therefore it is necessary to examine it closely.


18. Inspect The Reversing Valve


Some AC’s have the heat pump, which takes care of both heating and cooling of the home. It is the reversing valve that allows such units to switch between both. If the valve fails, so does the AC. It means that the air will still blow, but it will not be cool. Hence, the importance of inspecting the reversing valve. 


19. Check For Signs Of Rodent Infestation


Pests, critters, bugs, and rodents all prefer making homes in various parts of the AC. The problem with them is that sooner or later, they will try to chew the wires of the unit. So, the technician checks for signs of infestation and any damage that the rodents could have caused to the wires.


20. Overall Cleaning Of The Unit


The complete indoor and outdoor units of the AC are given a thorough cleaning to make it free of any dust, dirt, and debris. The surroundings are also checked to see that there are no obstructions that can restrict the flow of air.


Now you know all the major checks that an HVAC technician will carry out during the course of air conditioning tune-up. Armed with this knowledge, it’s easy to understand the importance of AC maintenance and our own limitation in carrying it out. It is a job best left to the professionals.


For faster scheduling, call us directly at 773.456.5883, or you can text or email us and someone will respond you to find a day and time that works best for your schedule.

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