Central HVAC systems more often than not have a system that is split into two, where some parts of the whole component are located within the building while others are located outside the building. The condenser that cools air is the main component located on the exterior of the building, and its main purpose is to extract and cool air before relaying it into the compartment of the system within the building. The exterior unit or condenser is turned on and off through the use of a contactor. The contactor is controlled by the thermostat, which is located inside the building. The thermostat measures the temperature and determines when cooling is necessary. Sometimes, the contactor malfunctions and the condenser continues to cool the air perpetually. In such cases, replacing the contactor is the only solution to the problem.
Replacing a Malfunctioning Contactor
Step One: The first step entails turning off the circuit breaker unit.Thereafter, open the side panel on the exterior of the house by unscrewing it. After turning off the breaker, the outdoor system portion should also be checked using a non-contact tester to ascertain that the power is effectively disconnected to avoid getting shocked.
Step Two: The second step involves determining the location of the contactor. Most units have one panel, which if removed, the technician or DIY owner can service the exterior and interior units in one go. However, not all units are manufactured or installed using the same design. Therefore, it is ideal to first consult the unit’s manual to get the proper diagrams. Typically, most contactors resemble a black box-like unit.
Step Three: In the third step, check for the visual location of the wire configuration of the system. Different makers of HVAC units have differing wire configurations, which are determined by the specific design used. If this process proves to be challenging, it is recommendable to consult the air conditioner’s user manuals.
Step Four: Make a sketch of the configuration of the wires on a piece of paper, and note the positions of the wires and their color so that the process of reattaching a new contactor will be easy. Thereafter, remove the contactor wires through a sliding motion from the unit’s contacts.
Step Five: After the removal of the wires, unscrew the screws that secure the contactor to the AC unit, and remove the whole contactor and place it aside. Wipe any rusty parts on the unit using a soft brush, and reverse the steps that were undertaken in step 7 and 8 to install a new contactor.
Step Six: Reverse the processes undertaken in steps 2 and 4 to reassemble the HVAC unit from its exterior, and turn on the circuit breaker to ensure that power reaches the electrical panel.
Finally, reset the thermostat located in the interior of the house to the ‘cool’ level and allow the system to go on and off repeatedly to ascertain that the contactor is working effectively. According to the Altitude Comfort Heating and Air website, any sort of air conditioner repair requires having the right tools, and the knowledge and understanding of air conditioning systems to be able to do the job properly.