S.M.A.R.T.
APPLIANCE REPAIR

air conditioning repair

The air conditioner is a common household appliance. It keeps you comfortable in your home when the outside weather gets too hot. The feeling you get when you come into a nice cool room from the scorching heat outside is priceless. Our timely air conditioner repair service will take away all of your unnecessary stress.

However, there is nothing more annoying than realizing that your air conditioner is broken on a hot day. Use good judgment and caution when attempting to check a few simple things before you start calling an air conditioner repair company like ours:

1. Check the power. Make sure everything is plugged in.
2. You can start by checking the settings on the air conditioner. Make sure that everything it turned on and to cool.
3. You can check out the controls. If nothing happens and you air conditioner still does nothing at all, you may need a new control panel.
4. If your air conditioner is working, but just not full strength or no cold air is coming out, check the blower. Sometimes the blower can get plugged with dirt and block the flow of the air. Cleaning the duct may solve the problem.
5. You can also check your filters. If they are dirty they may stop the airflow.

If nothing works, you may want to call a professional to diagnose and fix the problem.

Air Conditioners

Room and central air conditioners have some components in common with refrigerators and freezers. They have compressors, condensers, evaporators, motors, and various switches and links between these components. They share the basic function of moving heat and moisture from one place to another — from a room or area to the outdoors, thus lowering the temperature and humidity. Or more precisely, they move heated air across the evaporator, which cools it, and that air is moved by a fan into the room. The refrigerator behaves m much the same way excepting that it is usually a closed system in which warm air comes out of food, and the cold air from the evaporator isn't blown across the food.

Air conditioners deliver the cooled air by means of a fan, or in the case of the central system, by means of a powerful blower and ductwork. Blower and ductwork are normally part of the furnace, but they needn't be. The heat pump, which is an even more intimate combination of heating and cooling, does similar things.

An evaporator transports heat to the condenser, which is on the outside of the room or area. The condenser is usually in tandem with the compressor and is warm to the touch. It looks somewhat like an automobile radiator. In a central air conditioner, the evaporator is housed inside the supply duct chamber of the furnace, and it is usually drained from there by way of a tube or pipe into a basement or utility room drain of some sort, or a laundry tub.

The compressor is a pump which drives the Freon gas under pressure through the circuit. When the gas circulates, cooling takes place. A thermostat turns the compressor on or off, thus controlling the temperature in the room, exactly as in the refrigerator or freezer. However, refrigerator capacity is calculated precisely whereas room capacity is somewhat more elastic. Cooling will be somewhat less exact, therefore.

Air conditioning capacity is a key to performance. If the air conditioner is unable to meet the area's requirements, it cannot perform acceptably. Too often an air conditioner is accused of defective performance when its only flaw is inadequate capacity—in a smaller room it would work perfectly. But the cure is not to get a system with too much capacity. That will cool, but too quickly and won't remove extra humidity.

Two other keys to performance are the air filter and the condenser exterior. Condensers are exposed to incoming air and can become clogged with dirt or obstructions carried by the wind from trees (if outdoors as part of a central system). If the condenser becomes clogged, cooling will be reduced drastically. Once a year, you need to take the vacuum cleaner attachment to it. If you're cleaning a condenser in an outside condenser- compressor central installation, it is best to use a blower attachment and turn the air on the inside of it to blow the debris outward. If that's not possible, use the suction on the exterior. Sometimes the condenser becomes so clogged that you have to use a sturdy brush on it.

The filter is the regular furnace filter in a central installation; the small filter covering the window air conditioner is just behind the grille. It should be cleaned regularly, but the frequency will be dictated not by the calendar, but by the amount of dirt in the air. If you live in the mountains, your filter will take much less cleaning than in Chicago's Loop.

Your instruction book will tell you precisely how to remove the grille, if it isn't obvious—it usually is. Most of the window unit filters can be washed and replaced. Your furnace filter may be that type, or it may be the throwaway type.

To get at the condenser outside may require removing a lid or side from a metal housing. Because these units are outside, they are designed to be entered only with a certain amount of work and tools—not the usual burglar tools, but phillip's screwdrivers, socket wrenches, or what have you. (Outdoor units are not an uncommon item of thievery, so when you clean the condenser, after removing access panels, be sure to put them back as securely as they were.)

What can you do to a malfunctioning air conditioner? More or less what you can do to a refrigerator in a similar condition. However, the air conditioner does have the blower fan, which is an extra source of possible trouble. It can happen that the compressor and its motor work when the fan does not, with the result that you will get little or no cooling.

Fan motors in a central air conditioning unit are discussed elsewhere (under4 'furnace''). In a window unit, the fan motor is apt to be a smaller version of the "squirrel cage" blower and motor, but with the motor attached directly to the squirrel cage rather than belted as may be the case in a furnace plenum.

If you can feel cooling going on—the grille is cool — but no air is coming out despite the fact that the switch is on correctly, the first thing to investigate is the switch itself. Turn the switch off and on several times, making sure that it settles into its "on" position securely. A switch that turns the motor-compressor on is also likely to turn the fan motor on—that is, the contacts involved can be defective, but they usually will be the same ones that turn on the compressor. However, there are exceptions.

If jiggling the switch has no effect, you can test the switch with a light and probes after disconnecting one side of it that' goes to the fan motor. You can test the entire switch by disconnecting the leads, tagging them, and testing through each of the switch terminals — using the light and probes (with a plug-in wall outlet or battery-operated probes). The light should go on at each switch position. If it does not, replace the switch.

The next candidate for failure is the starting circuit, which is usually a capacitor in these small motors (refrigerator motors more commonly use startup windings, not capacitors). A capacitor is a condenser. The capacitor looks like a condenser, and it will have two terminals with clips on top of it. It will be near the relay a tubular can with a larger cable in it. Using a rubber-handled screwdriver, discharge the condenser by shorting across the terminals with the blade.

A faulty capacitor may be bulging or leaking — or it may have no visible symptoms. First check the clips for firm, clean connections. If you have an ohmmeter, you can test the capacitor. If not, replace it or take it to the shop for testing. Capacitors are inexpensive and not worth fooling with if the nearest shop is convenient.

It is possible but unlikely that the motor turns but the fan does not. You can see that by turning on the machine and watching. That merely requires tightening the setscrew for correction.

If the capacitor, switch, and wiring are in good order, and the fan still doesn't turn, the motor itself must be checked out.

An air conditioner actually has two fans — one that you can feel as it blows air into the room; the other, which is attached to the same motor, is on the outdoor side. These fans bring in air from the outside, or they circulate inside air through the air conditioner, and discharge it into the room. They can also circulate air without it going through the cooling process, if the switch has this bypass capability—most do. One of the fans is a squirrel cage, the other is a blade type. The motor is between them. Before examining the motor, check both fans. Hold one and try to turn the other. Neither should turn; if one does, tighten it. Remember — unplug the unit!

Testing a window unit fan motor can be done with a set of prongs and a wall plug or any arrangement that produces 115-volt current. You can test motors in other ways, if you have an ohmmeter. But the odds are that if the motor. If you've replaced the capacitor, take the motor out and either take it apart, as we've done elsewhere to check its brushes, bushings and commutators, or take it to a shop for estimate and repair, or simply buy a new one. Small fan motors are easy to work on, once you get to them. That isn't always easy. In a window air conditioner, it is. All other components in a window air conditioner can be replaced or repaired. Testing for leaks is the same, but the replacement or repair of components differs somewhat.

There is an order of component testing with window units: test the thermostat first, the relay next, the over-load, and finally the motor-compressor.

Tests are different from refrigerators because the components are themselves slightly different in location and configuration, hence access, even though they do more or less the same things.

The thermostat in a window unit is probably near or next to the switch or part of it. The knob with which you select cooling level will locate it — that's it behind the knob. Thermostat contacts, as we've noted elsewhere, can corrode. In a central unit, where the thermostat is located in the hall or some area that most reflects desired temperatures rather than in the unit itself, you can remove the cover. When the dial and cover come off— usually they just pull off — you can see the contacts (two sets — one for heating, one for cooling), though there may be a plate covering them which is screwed on and off. You may also see a bulb or tube sensor. Clean off the contacts with light sandpaper. In some cases that will cure the problem of no cooling or inadequate cooling in central units.

In window units it is unlikely that the contacts will be exposed. The thermostat will be an enclosed rectangle or container that comes out easily—pull off the leads, being wary of the bulb, if it's that kind rather than the simple bimetal type, and unscrew the thermostat. If it's the bulb type, it has to have the bulb in the right position, so make note of the position.

Thermostats are sensing devices for passing or interrupting electricity when their contacts close or open. Obviously this happens at certain temperatures with air conditioners or refrigerators. With air conditioners, it's usually between 65 and 8(FF (16 to 26°C).

Put it on some ice cubes to cool it, and it should click when it goes off. Put it near a source of heat, and it should click when it goes on. If it does not, replace it. But the click is not loud and in some cases may be so faint that it is deceptive — you think you hear it but don't.

Central unit thermostats are expensive, not so window units. If there's any doubt, replace the unit — that advice also holds with the central unit. It's far cheaper to replace a central unit on your own than to call a serviceman to do only that. He will add the retail cost of the unit to his service charge, both of which you could avoid at some supply houses where discounting prevails. But a central unit should be checked carefully before replacing it because of its cost, whereas the window unit will cost far less.

To test a central unit thermostat is mostly a test for continuity, and you can do that with a battery and 12-volt test light, if you have such a device, or even a 6-volt light. When the contacts are open (cool), there will be no light; when closed (hot or warm), the light should go on. Otherwise there is no continuity; the thermostat is defective. To test the relay switch, find it on the room side of the window unit (it probably will be outside with the motor-compressor and overload switch in a central unit). Disconnect its wiring; test it for continuity, and because normal position is open, it should have no continuity — that is, the light on your test light should not go on. If it does, the relay is defective. However, relays can become defective in tricky ways, other than their contact points sticking together. Points can get corroded sufficiently to disturb current flow. That will show up in listless performance or other strange behavior which cannot be explained on other grounds—dirty filters, etc. If relay contacts are visible, which they are in most cases of central units and some cases of window units, look at them. You can see wear — corrosion, pits, burning. File them, and they will work, at least for a considerable time. Use sandpaper, not emery cloth.

If the relay is in an airtight can — a common possibility — there is no inspecting it. The can will be larger than the capacitor, which will be nearby. If it fails the continuity test (above), buy a new one. The cost isn't great. Testing an overload switch is identical with testing such a device in any refrigerating system. Test it for continuity. Overloads fail less often than other electrical components, but if you have to replace a relay it makes sense to replace the overload as well. That's because a relay will cause the overload to overwork before it expires. An overworked overload switch will be next in line for expiration.

You should use an ohmmeter on the motor - compressor, if that is to be tested, everything else having tested out in good order. Disconnect the motor — that is, the appliance — and use the ohmmeter probes on it. The reading should be about 20 ohms. If there is no reading on the ohmmeter, you need a new motor. That probably means a new air conditioner, unless it turns out that a professional shop will repair it for a lot less than the cost of a new one. Sometimes this can happen, but replacing a motor-compressor in any air conditioner is subject to all the complications we've discussed under refrigerators. It can be done, but should only be commenced with all the complications in mind and all the necessary tools and skills in hand.