It's starting to hot in Texas. I have a refrigerated air window unit in my office so I don't have to cool the whole house down to remain comfortable while answering iFixit questions. It has a removable plastic filter on the inside of the house that can be removed and washed. Behind that are the radiator coils. Those are dirty and I would like to clean them without making a big mess. Does anyone know how to do this and any other yearly maintenance things I need to do before starting it up for the year? To start use a vacuum cleaner with a soft brush hose attachment to get rid of the loose stuff. Then you are going to want to use a degreaser/ cleaner to spray on the evaporator. I would suggest a foam based one such as this to keep the mess minimal. You may notice the product I suggested is self-rinsing, which means it will only need wiped off. To wipe it off between the fins use a fin comb. Fin combs come in different sizes and styles. To pick the proper one measure the number of fins per inch and purchase one that has the matching comb.

Most of those are plastic. I could not find one like mine which is more like a disposable razor with different sized interchangeable blades. I've got 10 combs/blades for mine. Click here for an example of the plastic one I have. They seem to be coming in some kind of a rotating circle set up now. These can also be used for straightening out bent fins. They also make universal fin combs. Please click here for an example. The universal ones do a good job for cleaning ( I have one for that purpose only.), if the fins are not bent, I would not recommend using one to straighten bent fins. You will want a bucket of water and some paper towels for cleaning the comb between strokes. Insofar as recommended maintenance. Clean and straighten out the inner and outer fins on both the evaporator and condenser. That will ensure good air flow and efficiency. Clean the fan blades and if the fan has an oil port add some oil (3n1 electric motor oil). If you have a clamp on amp meter use it to compare the amperage draw of the unit to the rated amount on the specifications plate provided by the manufacturer, if there is more than a 25% difference you may consider having it professionally serviced - if you are not happy with it's performance.

Freon systems are closed systems and if they are leaking it is most likely through a compromised piece of metal or a joint. With age compressor motors do tend to draw less current, so a difference in plate rating and actual current draw does not always indicate a loss of freon in the system. air handling unit vs package unitYou can do what is called a wet bulb test. installing a window ac unit in a wallUse a quick reacting thermometer where the air is coming in to be circulated. used commercial air conditioning equipmentTake another quick acting thermometer, wrap it's sensing part with a wet paper towel, place it where the air is leaving the unit to "cool" the room. Let the AC run for 10 minutes. There should be approximately a 20F difference between the two if the system is in good order.

I don't think it can be done without some mess ... condensation has probably glued the dirt/dust to the coils... Take it outside to brush and wash/rinse with soapy then clean water would be, IMnsHO the best way. if you have to do it inside you might get by with putting down a tarp (or using bathtub/shower stall) and using a hand pump up sprayer (like for liquid weed killer, or deck wash/sealant) to get some pressure behind the water. These units (all AC units actually) lose freon (coolant) as the molecules are so small they pass through most rubber hoses & seals - that affects efficiency of cooling. Take it, or call an AC specialist to come over, who can run a pressure test and top off the coolant (which also contains pump lubricant). As always "if this answer is acceptable"... you know what to do. Apartment complex I was at... Mexicans Really Good at these tings... Pull unit, unplugged, hose down. let dry over night make sure is dry. Mine cleaned nicely three times last summer & one before.

Dusty here in Arizona. Use a can of compressed air. Always be careful not to bend or displace the fins on your coils. If the fins are not damaged do not touch them with anything. Cleaning your air filter regularly and checking your coils twice a year are two of the most essential preventative maintenance tasks you can perform on a window unitDuring the hottest days of the year, it’s likely that you rely heavily on an air conditioning unit—be it targeting your room from a windowsill or cooling off the whole-home—without considering what makes it tick. Your AC condenser coils are where the magic happens: Here, the refrigerator unit in your go-to seasonal appliance absorbs heat to make the air cooler. As air passes over the cool refrigerant, it wicks the heat out in a process that’s essentially the reverse of how your forced air furnace operates. Now, the cleaner the surface area of those coils is, the more efficiently the machine works. Dust and oil that accumulate over time can create a blanket over the coils—one that, just like the blanket on your bed, impedes heat transfer and makes your AC less efficient and more expensive.

Fortunately, the hardest part to cleaning air conditioner coils is remembering to set aside the time at least once a year. The process takes less than half an hour, but better schedule a full hour so you don’t feel like you’re rushing through the job. - Fin brush (optional) - Foaming coil cleaner For window ACs, you’ll need to access the end that sticks out of the house in order to reach the coils; central air units typically keep the coils behind a removable panel that you should unscrew in order to continue. Check your operator’s manual if you’re unclear—the specs diagram will identify exactly where the coils are and the process to remove the cover, if applicable. Remember: When in doubt, trust the manufacturer. They know how to take it apart. Visually inspect the coils for any large debris like leaves, spider webs, or clods of dirt. Remove these by hand, then dust off the coils using a coil brush. Available at most big box hardware stores and AC shops, this specialty cleaning tool (also known as a soil brush) features bristles with stiffness about halfway between a hand broom and a wire brush.

Lightly guide the brush parallel to the fins on the coils in order to avoid bending them. This isn’t a deep scrub—you’re simply knocking off loose dust and hair. Did you notice many bent fins on your coils in Step 2? (Hint: Bent fins will reflect light and often put a bright sheen to parts of the coils.) If so, running a fin brush slowly and parallel to the line of the fins could straighten them out. This will improve the performance of your AC unit by increasing the exposed surface area for the coils. If you don’t want to invest in a piece of specialized equipment like the fin brush (which can be purchased for $15 or more online), go ahead and skip this step. Correcting bent fins goes above and beyond the task at hand—cleaning the coils—from which you’re machine will already receive an efficiency boost. Rinse the coils on any outdoor central AC unit by spraying with water from your garden hose. If your unit is indoors, you can avoid a puddle beneath your window altogether by opting for a slightly pricier “no-rinse” type of coil cleaner and moving on to Step 5.

Shake the can of foaming coil cleaner—either the standard or a no-rinse version—and spray it directly into your coils so that none go uncovered. The cleaner should foam immediately, filling the air between coils where grime accumulates, until each section of your coils is hidden from view. The foaming lifts off all the unreachable dirt and grime embedded in between the fins. Let the cleaner soak for five to 10 minutes, according to the instructions on the can. If the cleanser specifies, rinse off the foaming cleaner using your hose. You will need good water pressure and slow, back and forth motions to thoroughly rinse the cleanser off. Indoor units cleaned using rinse-free cleaner simply need to start up; the condensate will rinse off the cleaner on its own. Though some of the more unscrupulous AC service companies will say you need service two or three times per year, most experts agree cleaning your coils once a year is plenty. For best results, do it in the spring, immediately before the summer heat starts to demand your air conditioning perform at peak potential.