Now that we have seen how an air conditioner does the work, let's look at the mechanics involved. We can see that there are two main systems in a roof top air conditioner, the sealed refrigeration system, and the air handling system. In addition to these systems, there is, of course, the control system (thermostat and fan switches).For the sealed system, all brands, Coleman, DuoTherm, Carrier, Intertherm, and others, work the same, using the basic principals of refrigeration. In the sealed system, the main component is the compressor- which, by itself, is not serviceable, but there are some components that are external to it which are serviceable. For now, let's look at the most common and easily repaired problems. The one major compromise that roof top air conditioners all have in common is the fact that they all have to route both the return and supply air through a standard 14" by 14" cutout in the roof. This is even more amazing when you realize that the average 13,500 btu air conditioner has just over 1 ton of cooling capacity- a 15,000 btu model is around 1 1/4 tons.

A motor home or large trailer that has two 15,000 btu air conditioners has 2 1/2 tons of air conditioning- or enough capacity for many houses. The two most common complaints are "Not cooling enough" and leaks. Let's look at "not cooling" first. Not blowing cold air. The first thing to determine is if the compressor is coming on. If it isn't, it is likely a control problem with the thermostat or relay board (if you have a wall mounted thermostat). If the compressor is coming on, then you need to look into the airflow of the unit. Whether or not the compressor is coming on, you need to check the voltage. Like every appliance on board, the air conditioner needs adequate power to operate. If the voltage is 110 volts a.c. or below, the effectiveness of the unit will start to suffer. After verifying correct voltage, we need to look at how the air conditioner does it's job- it requires adequate air flow over both the inside (evaporator) and outside (condenser) coils. If the air filter is clogged refrigerant will not be able to pick up enough heat from the inside air, and if the condenser coils are blocked by leaves, it will not be able to give off enough heat to the outside air.

Most RV rooftop air conditioners have washable filters, which can be vacuumed or rinsed off in a sink to clean. If you are in summer weather where the air conditioner is running 24 hours a day, the filters should really be at least vacuumed once a week. Note that if the filters have been neglected, the evaporator coils probably need cleaning as well. These can be seen when you remove the air filters, and possibly the inside air box. wall ac unit saleLikewise, the condenser coils can be seen after removing the upper shroud. air conditioning units to hire londonNote that some air conditioners draw air in from the back, and some blow air out the back. air handling unit detailsYou will need to determine which your is, or just check both sides of the condenser.

An unavoidable drawback to being able to mount an air conditioner in a 14" by 14" roof vent cut out is that both the supply air and the return air are in very close proximity to each other. This can be a problem if the two are not sealed well from each other- if the cold supply air can recirculate into the return side, the evaporator coil can easily freeze up, plus that is cold air that is just going to waste. Note that this is normally more of a problem with ducted type air conditioners than the standard exposed air box type, but it is something that you need to be aware of, in all cases.A fairly easy way to check is to simply, carefully put your hand into the return air duct and feel for cold air. If you can feel cold air, you need to take care of the air leak. The last problem we will talk about is heat gain. One compromise that most RVs make is in the insulation department- after all, if they had 6" thick walls for good insulation, there wouldn't be much living room left, so..

In very hot weather, and direct sun, the amount of heat that the RV will pick up may be greater than the amount of heat the air conditioner will pump back out. In this case, shade is the answer! Whether you use an awning, or an oak tree, in very hot weather, keeping the direct sun off of the RV will greatly increase your comfort.Since their development in 1902, modern air conditioning units are efficient and relatively trouble-free. Like other major appliances, the equipment can experience mechanical or electrical problems. This guide provides an overview of some of the most common problems that can occur with a central HVAC system. Northwest Indiana homeowners can troubleshoot their systems to identify potential reasons for performance issues. While homeowners can resolve some of these problems, others require the assistance of an experienced heating and air conditioning specialist. An air conditioning system may fail to operate at the beginning of the cooling season. The unit will not come on if the thermostat is defective or set improperly.

Another potential issue may be that your unit is not receiving electrical power. Verify that your thermostat selector is set in the “cooling” position. Some systems have a built-in timer that delays the activation of the equipment. Wait several minutes for the timer to complete its cycle, and adjust the thermostat several degrees below the temperature inside your home. If the thermostat requires calibration, contact a service professional. You should also verify that the appliance is receiving power. Locate your main fuse panel, and determine whether the fuse or circuit breaker for the equipment has blown or tripped. Replace a blown fuse with one that has the same amperage, or reset the circuit breaker. Some units have a breaker panel located near the outside unit. Verify that the breaker inside this electrical box is on or the quick disconnect is inserted properly. If the system continues to have electrical problems, you need the assistance of an experienced repair technician.

One possible reason that HVAC systems blow warm air is dirty filters. The system is producing cold air but it cannot flow through the ductwork. Clean air filters protect your equipment and help it perform properly. HVAC systems work harder as the outside ambient temperatures approach triple digits and may not cool as effectively as you desire. You should also verify that the outside unit is running. If the outdoor unit is on, ensure that leaves and other debris are not obstructing the airflow. An air conditioner that blows warm air can be a sign of insufficient refrigerant. Only licensed air conditioning repair technicians can replenish HVAC coolant. An improperly sized air conditioner will cycle on and off frequently if it is too large for your home. The system will quickly reach the setting on your thermostat and signal the equipment to cycle off. When the temperature drops below the setting on the thermostat, the unit will come on again. Rapid cycling can also occur when an air register is blowing cool air directly on the thermostat.

Several issues can cause a unit to runs continuously. The equipment could be too small to cool the volume of air contained in your home. Another potential problem is that the inside unit turns off but the outside fan continues to run. Turn the thermostat fan switch to the “Off” position. If the fan is still running, you should stop power from flowing to the system. To perform this task, it may be necessary to turn off the circuit breaker supplying the equipment. Low refrigerant levels and faulty relay switches can cause a HVAC to run continually. An experienced HVAC technician can correct these problems. The inside component of an AC system sits inside of a drip pan, which is designed to collect water if the unit’s condensation drain line becomes clogged. This problem can occur when insects build their nest inside the drain line. If water is visible in the pan, you can blow compressed air inside the pipe to remove the obstruction. Prepare a solution that consists of a 50-50 ratio of bleach and water, and pour it into the drainpipe to eliminate mold and mildew.

Clearing the clogged drain line may require the assistance of an air conditioning repair technician. Various problems can cause an AC unit to freeze. One possible reason is improper airflow, which can prevent a HVAC system from working properly. Check your filters and clean or replace them as required. The coils should be free from dirt, debris and other obstructions as well. HVAC systems can freeze if the blower fan is malfunctioning. The cold air will remain inside the unit and freeze the coil if the fan is not working. A faulty control relay can also cause the unit to freeze. The outside unit will continue to run even though the inside unit is off. While a homeowner can clear away debris and change the air filters, replacing electrical components requires the expertise of a certified technician. According to heating and cooling industry studies, regular air conditioning unit maintenance checkups can prevent most HVAC performance issues. Our friendly and knowledgeable Meyer’s technicians can perform seasonal tune-ups on your system.