It happens to everyone at some point. You notice that your house is warming up when it should be cooling down. You feel air from the vents, but you look outside and notice the condenser isn’t running. What do you do now? Call an HVAC company and have them send a technician like myself out as the customer did in this case, or if you are the type to attempt to figure it out yourself. Whether it is a major brand like Trane, Carrier, Goodman, Raheem, Ruud and Lennox, or a lesser brand like Coleman, York, Luxaire or Concord, there are a few things that you can check and repair yourself with ease.
Power
The first thing you should check is the breaker to be sure it isn’t tripped. If it is tripped, try and reset it by switching it all the way to the off position and then back on. If this solves your problem, you may have just had a power surge. If the breaker trips again, you have a larger issue that needs attention. You can also check the outdoor disconnect. Some disconnects contain fuses in the pullout. Be sure to check the fuses.
Wiring
Now that you have checked the breaker and the power at the outdoor disconnect, The next place you want to check is the condenser itself. With the disconnect pulled and power off to the condenser, open up the electrical compartment door. This is easily located by following the electrical conduit that runs to the condenser. Remove the screws that hold the cover in place and do a visual inspection. During the winter and spring months, rodents will sometimes get into the electrical compartments and make a nest. They can chew wires and damage the unit as in the case below, that is exactly what happened to the unit. We removed the nest and repaired any damaged wiring. Also, be sure to check the thermostat wiring running from the house to the condenser.
Capacitor
A capacitor is a power storage device, similar to a battery but delivers much more power to a motor enabling it to start and run. The capacitor on a condenser will generally be a “dual capacitor”. This means that it combines two capacitors into one. One, smaller mfd for the fan motor and one larger mfd for the compressor. When these fail, sometimes only the fan will stop running or sometimes only the compressor. Many times you can tell that a capacitor has failed just by its appearance. The top will no longer be flat and will become blown out and rounded on top, or be completely blown off.
Contractor
If you have 24 volts to the coil of the contactor and the contactor does not close, the contactor is bad and needs to be replaced. If you don’t have 24 volts to the contactor coil but have 24 volts at the low voltage wire nuts, you are likely off on low-pressure safety and will require a visit from a certified HVAC technician to address the refrigerant issue.
VIRTUAL DIAGNOSTIC
If you still have not been able to figure out the issue using the information provided above, you can talk directly to a certified HVAC technician to help you resolve your issue through a one on one video consultation by clicking the virtual diagnostic button on our home page or click the link here… Virtual Diagnostic