Jan 18, 2021
에어컨 can help prevent sinus congestion, sneezing and other allergies. But air conditioning can also pull moisture from your skin, which can make it dry and irritated. This can raise your risk for “sick building syndrome.”
When you rent an air conditioner, it’s important to understand what a ton means. A ton in AC is based on how many BTUs your unit absorbs and removes from your home.
Condenser
The condenser unit is the large outdoor unit that houses several essential AC system parts, including the evaporator coil and compressor. It also contains a fan that blows air over the coil to release heat as it dissipates. This unit is the heart of your home’s cooling process, so it is important to take good care of it.
The air conditioner works by transferring heat from household air in the evaporator coil to a gas called refrigerant. This refrigerant then travels to the outdoor unit, where it is cooled by the surrounding air. This cools the hot, pressurized gas, which then returns to the evaporator coil in your home. The evaporator coil absorbs this latent heat, which lowers the temperature of the air in your home.
The evaporator coil can only transfer so much heat, so the condenser coil rejects this excess heat to an external medium. This is typically air, but can be water or a combination of the two. It is essential to keep this flow free from debris, such as plants, grass, and other growth, and to make sure it has plenty of space to work in. Dirty coils can lead to lower efficiency, higher amperage draw, and shorter equipment lifespan. It’s a good idea to include a regular cleaning of the condenser unit as part of your annual air conditioning maintenance plan.
Evaporator
The evaporator unit is where cool air comes from. It consists of a coil filled with copper tubes and fins that allow the refrigerant to mingle with the hot air in your home. It’s hard to access and is one of the reasons why it can take a pro between six and eight hours to replace an evaporator coil.
The coils are made of copper, which is good because it conducts heat really well. But it also rusts really easily. That’s why you want to keep a close eye on your evaporator coil for signs of rusting or other damage.
A dirty evaporator coil can make the air conditioner work harder to achieve the desired indoor temperature, which will increase your energy costs. The evaporator coil can also become clogged with dust, which will impede airflow and cause water vapors to freeze on the coil.
The coils can also develop a corrosive coating called formicary corrosion, which is very hard to get rid of. Oftentimes, it will need to be replaced entirely.
Compressor
The compressor is the heart of your air conditioning system. Powered by your engine’s drive belt, it draws in R134a and compresses it into a high-pressure hot gas ready to enter the condenser. The compressor itself consists of various components that must work together.
There are many different types of compressors. Most use a piston and cylinder design to compress the refrigerant. Various kinds of rotary compressors are also available, including rotary vane, scroll and screw designs.
Regardless of the compressor type, the job is the same: to create a higher concentration of pressurized refrigerant so it can be sent on its way to the evaporator. The compression process is accomplished through mechanical energy, so the compressor must be properly lubricated and maintained to ensure proper function.
Single stage compressors were the AC standard for decades and still make up the majority of air conditioning systems today. They operate continuously at 100 percent capacity to maintain the temperature set on your thermostat.
The compressor features coppers wires known as windings that are used to conduct electricity inside the unit. If these wires become damaged, the compressor may experience a short to ground, which is when electricity is redirected away from its intended path and onto the compressor’s metal components. This can cause a squeal of high-pitched noise as the bearings within the compressor begin to wear out.
Fan
The fan unit is responsible for circulating the air throughout the ductwork. It has a fan, a coil, interior insulation (liner) and a replaceable air filter. The air is drawn in through a vent, passes over the coil which heats or cools it depending on the season and then is blown back into the room.
There are two settings available for the fan on the thermostat – AUTO and ON. Running the fan on the AUTO setting will save energy by only running it when the system is cooling. This will also reduce the amount of wear and tear on the blower motor as it won’t be running continuously.
Another benefit of the AUTO setting is improved dehumidification in the summer. The continuous running of the fan allows moisture that drips off the cold cooling coils to be blown out of the ductwork and down into the drainage pan.
Most modern FCUs have a terminal control that has the capability of adjusting the fan speed based on space heating/cooling demand. It does this by monitoring the temperature within a space and making adjustments to both the fan and valves. The result is a much more efficient system as it doesn’t have to work so hard to achieve the desired temperature for occupant comfort. Alternatively there are other methods of regulating the fan motor speed such as differential pressure switches. These are installed in the ductwork and operate by penetrating the duct with pick-up tubes on both sides of the fan and connecting these to a mechanical switch with a single adjustable trip point.