Your home’s central air conditioning system is a critical component when it comes to your cooling your home. When repairing your system, installing new equipment or maintaining existing equipment, important considerations need to be taken before getting started. Understanding how your central air conditioning system works, required maintenance procedures and easy cleaning and repair tips will help you care for your system. It will also help you best know how to start your central air conditioner installation and repair project.
How A Central Air Condition System Works
A central air conditioning system is comprised of two main components referred to as a condenser (3) and an evaporator (1). The condenser resides on the exterior of your home, usually placed on a small, concrete slab where it is easily accessible. The evaporator, including the evaporator coil and air handler or blower (2), is strategically located inside the home, usually in a closet dedicated to the unit. The evaporator might be located in the attic as well. In homes where a furnace is used, the evaporator will reside above it where it connects to the plenum or a duct junction for air distribution. If you do not have a furnace or other heating source, your central air conditioning system may be equipped with an electrical resistance heating element to provide your home with warm air during the winter months. Since we are talking about a central air conditioner, this article will focus mainly on the cooling aspects of the system.
In either case, a central air conditioning system falls under the forced air distribution category, meaning the same ductwork, motor, and blower are used for both heating and cooling your home. Once the unit is activated, hot air is drawn from the house into the return air vent and pulled across the evaporator coil to cool it. The fan and blower assembly provide the circulation to draw in and distribute the conditioned air through the ductwork to cool the house.
Annual Maintenance and Repair of AC Unit
Central air conditioners require a high degree of training, knowledge, and experience to repair properly. Both of the main components—the evaporator and the condenser—are sealed units; therefore, special training and tools are required to service them. To maintain peak performance and efficiency of your central air conditioning system, schedule an annual inspection, adjustment and cleaning for preventive maintenance with a reputable contractor before the summer months set in.
Choosing the right contractor is as important as maintaining your heating and cooling system. Before hiring an HVAC pro, verify that your contractor is licensed and insured. The BBB (Better Business Bureau) is a great place to start, as they will have any complaints, lawsuits, or concerns on file regarding the applicable contractor. Ask the contractor for a list of references with phone numbers so that you can call and ask about the quality, cleanliness, and timeliness of the work performed.
Upon arriving at your home, and after introductions are made, the contractor will begin his/her inspection, including adjustment and cleaning procedures. A thorough cleaning and inspection should include the following:
- Lubrication of any moving parts such as blower fan motors, fan blades, and condenser fan.
- Verifies refrigerant levels are correct and adds freon when necessary.
- Performs various safety checks on the system.
- Inspects and cleans the evaporator coils.
- Inspects and adjusts any contactors, wiring and related connections.
- Inspects and tests capacitors and relays within the system.
- Verifies the condensate drain is free of obstructions and is draining properly.
- Cleans the condenser coil.
- Inspects the outdoor disconnect.
- Inspects condenser fan motor and blades.
- Performs an amperage startup test on the compressor.
Service contracts for annual preventive maintenance are available through many HVAC contractors and companies. Benefits often include:
- Annual preventive maintenance inspections and adjustments.
- A discounted preventive maintenance price.
- Possible discounts on parts and labor.
- Bumped higher up on their priority service call list.
Do Your Part
The benefits of annual preventive maintenance checkups on your central air-conditioning system far outweigh the costs of repair service. With regular preventive maintenance checkups, you can expect:
- Peak performance from your central air conditioning system.
- Increased energy efficiency as a finely tuned and maintained unit will consume less energy, reducing your energy costs.
- Early warning of potential equipment failures in the future.
- A peace of mind knowing your home’s central air conditioning system is in A1 condition and using energy efficiently.
Annual preventive maintenance contracts are great but sometimes trouble arises in between appointments. Although most central air conditioning repairs require a professional, there are some things you can do to troubleshoot and even correct your home’s system.
- When your system loses its power, check for tripped breakers or blown fuses in the circuit breaker box. However, use extreme caution when working around electricity.
- If the system is running but not cooling, try lowering the thermostat settings by 5 degrees.
- The system is running but air is not coming out of the vents. Check for a dirty filter and replace if necessary. A dirty filter can lead to ice forming on the evaporator coil, which will prevent airflow.
- Clean the evaporator coils. A dirty evaporator coil can also lead to ice forming on its coil, prohibiting airflow. Find detailed instructions below.
- Inspect the condenser outside unit coils for dirt, debris and vegetation that can impede airflow to the compressor. If the compressor cannot breath, it could overheat and shut down.
If you forgot to change the filter or ran your system without one, which happens more often than you would think, your evaporator coils might have gotten dirty. Therefore, you find yourself 6 months before your next scheduled cleaning and maintenance call wondering what to do. No sweat, most homeowners should have no trouble cleaning their evaporator coils themselves and preventing a costly service call. Gather the following items before starting this project:
- A bottle of coil cleaner sold at most hardware, A.C. supply houses or home improvement centers. If you are unable to locate the coil cleaner, a household bathroom cleaner such as scrubbing bubbles will suffice.
- Protective gear such as safety goggles and rubber gloves.
- A drop cloth to protect flooring.
- A flashlight.
- Two plastic spray bottles.
- A wet/dry vacuum cleaner.
- Clean rags.
Step 1. Turn the power off to the central air conditioning system at the circuit breaker box.
Step 2. Remove the air filter on the evaporator unit to expose the underside — the side most exposed to dirt and debris collection — of the evaporator coils.
Step 3. Clean the area beneath the evaporator when applicable and vacuum as much of the loose debris from the evaporator coils as possible.
Step 4. Mix the coil cleaner when applicable with clean water according to manufacturer’s instructions. Some coil cleaners might not require mixing with water so read the instructions carefully.
Step 5. Apply the solution liberally to the evaporator coils using the spray bottle. Be sure to wear your safety goggles and rubber gloves to prevent injury.
Step 6. Rinse the evaporator coils with clean water using a plastic spray bottle.
Step 7. Vacuum entire area and wipe up excess solution, dirt or debris with clean rags.
Step 8. Install a new filter.
New Central Air Conditioner Installation
Homeowners lacking the extensive knowledge, experience, training and specialized tools required to install a new central air conditioning system should never attempt to install one. This project will require a highly trained technician with the experience to complete the job successfully. Steps a homeowner should take before hiring a heating and air conditioning contractor are listed above under the maintenance section. However, there are certain projects a homeowner can do before the technician arrives to install the new system.
- Apply caulk around window and doorjambs to prevent conditioned air from escaping.
- Seal any cracks, crevices or holes in exterior walls to prevent conditioned air from escaping.
- Clean all return and vent registers applying paint when necessary. This can save you a few dollars versus replacement.
- Have an insulation contractor determine if you need additional insulation in attics and crawlspaces.
- Remove any clutter around the evaporator closet and outside condensing unit before the HVAC technician arrives.
- Insist the technician replace the copper supply lines with new ones. Although this is not necessary in most cases, it is better to be safe than sorry later. When a compressor burns out, there is a chance the copper lines can become contaminated with acidic residue that you would not want to introduce to your new system.
- Hire an electrician to inspect HVAC wiring and replace or upgrade when necessary.
- Homeowners should also consider having their furnace when applicable inspected before new installation.
Central Air Conditioner Installation Considerations
Have your contractor help you determine if you need new ductwork. In most cases, a simple cleaning will suffice, but it doesn’t hurt to weigh your options beforehand.
You’ll also want to decide if you’re going to relocate your system, which could increase the cost of installation since more work will be required. Relocation can boost the efficiency of your unit. It may also be necessary because of planned or existing room additions, or if the system was placed poorly in the first place. A good example of poor placement would be the evaporator in the attic or the outside condensing unit next to a patio or bedroom window.
Central air conditioning systems are complex pieces of machinery. This information will help you understand the procedures required to have a successful central air conditioner installation and repair project.