If you already have a newer condenser, the worst noise is probably coming from the compressor. (Fans on newer units are very quiet.) Contact the manufacturer to find a sound blanket for your model or buy a universal blanket (search online for “compressor sound blanket”). Installation is easy. Don’t bother putting a blanket on an old unit—you’ll still hear the noisy fan. Here are other possible solutions for a noisy air conditioner.
Finally, don't underestimate the thermostat as a potential reason why your furnace is not working. Everything on the heating unit itself may function perfectly, but your home still will not heat right if the console you use to set the temperature doesn't communicate your input. A faulty thermostat can either be due to the wall unit itself, or the wiring that connects it to your furnace. Average thermostat repair costs are between $108 and $282, including labor. Replacement costs, of course, depend on the thermostat you choose. Visit our thermostat repair cost guide to learn more about this type of issue.

The fan limit switch controls the furnace blower. The fan limit switch has three settings: “Fan On”, “Fan Off”, and “Limit”. In the “Fan Off” setting, the blower will only operate if there is warm air in the plenum to prevent cool air from blowing into the home. The “Fan On” setting will keep the blower operating even after the burner has shutdown, making sure that all of the hot air produced is circulated. The “Limit” setting is a safety control that will turn the burner off in the rare event that the air in the warm air plenum reaches an unsafe temperature. This may be the case if ducts are blocked or if the system controls are malfunctioning.
When you contract with Vredevoogd Heating & Cooling Grand Rapids MI, you can count on us to make safety our top priority. Your HVAC system is, of course, a major investment and integral to the functioning of your home; however, nothing is as important as the safety of each life within your home. We carefully inspect your system to ensure that it is functioning properly in order to guard against carbon monoxide poisoning or other system emergencies. We take the greatest care when installing your HVAC system, knowing that a perfect installation is the safest installation for your home. We follow our industry’s best practices concerning safety and will happily share our know how with you when it comes to safely maintaining your system between service appointments.  If you ever suspect a problem with your HVAC system, you hear strange noises or smell unpleasant odors, for instance, you can call us night or day, 24/7, to address your heating and cooling emergency. We’ll never leave you in the lurch! We are ready to provide service ASAP to ensure the safe operation of your HVAC system.

Replacing a capacitor is easy. Just take a photo of the wires before disconnecting anything (you may need a reference later on). Then discharge the stored energy in the old capacitor (Photo 4). Use needle-nose pliers to pluck one wire at a time from the old capacitor and snap it onto the corresponding tab of the new capacitor. The female crimp connectors should snap tightly onto the capacitor tabs. Wiggle each connector to see if it’s tight. If it’s not, remove the connector and bend the rounded edges of it so it makes a tighter fit on the tab. When you’ve swapped all the wires, secure the new capacitor (Photo 5).