Evaporative Coolers

What is an evaporative cooler?

An evaporative cooler, also known as a swamp cooler, wet-air cooler, and desert cooler, is a device designed to cool air via the evaporation of water.  This is a natural and energy-efficient way to achieve a comfortable indoor temperature.  An evaporative cooler cools indoor air by drawing outdoor air into the unit and passing it over pads that have been saturated with water from a reservoir in the unit.  The water evaporates into the air as it passes over the pads, and the result is a 15° to 40° drop in temperature.  The cooled air is then directed through interior areas where a lowered temperature is desired, forcing warm air outside through open windows.  Because of this, evaporative coolers steadily circulate fresh air through the interior, unlike air conditioners, which circulate the same air over and over again.  They also cost far less than air conditioners and use around a quarter of the energy, making them a very efficient alternative.  

How does evaporation work to lower air temperature?

This process can be observed naturally near a waterfall, lake, river or ocean. When dry air passes over water, the air absorbs some of the water.   The air temperature drops because the temperature and vapor pressure of the water and air attempt to equalize.  Until the air is saturated and unable to hold any more water, liquid water molecules turn to gas in the air, a process that uses energy to change the physical state of the water.  Heat moves from the higher temperature of the air to the lower temperature of the water, which causes the air to cool.

How an Evaporative Cooler Works

An evaporative cooler is basically a large fan with pads, moistened by water, which are located in front of the fan.  The fan pulls the hot, outside air inside, and the air is cooled after passing over the wet pads.  The pads are usually made from wood, wool or fiber, though some plastics and melamine paper are now also used to make cooler pads.  However, wood absorbs some of the water, which allows it to cool the passing air to a lower temperature than some synthetic materials.  The thickness of the pad also plays a part in the cooling efficiency because a larger pad allows longer air contact, so a 10-inch pad is more efficient than a 4-inch pad.  The pads need to be replaced every season or two, but they are fairly inexpensive.

Small water distribution lines wet the top of the pads, which become soaked.  Once the water trickles through them, collecting at the bottom in a sump, a small re-circulating pump sends the water back to the top of the pads to soak them again.  When enough water is lost through the evaporation process, a float valve adds water to the sump so that the pads can continue to be soaked.  Under normal conditions, a cooler may use between 3 and 15 gallons of water per day. 

Because evaporative cooling takes air from the outdoors, cools it, and circulates it indoors, there must be a way for the warm air inside to escape when it is displaced by the incoming cool air.  By leaving doors and windows open strategically, it is possible to direct the path of incoming cool air to areas where it is needed most.  Even smaller units can be effective for larger areas when used in this way.  Many types of cooling units are currently manufactured, including small units for installation in windows, as well as large units meant to be installed centrally to blow air through ductwork and into individual rooms.  

Evaporative Cooling vs. Air Conditioners

The most important factor to keep in mind when determining whether an evaporative cooler can be utilized effectively in a particular situation is the moisture content of the outside air.  Since the air will not hold additional moisture once it reaches its saturation point, no drop in temperature will occur through evaporation if the air is already saturated.  Because of this, evaporative cooling cannot be used effectively in wet or humid climates.  Meanwhile, in areas where the air is hot but humidity is low, the coolers can be used as a cost-effective and energy-efficient alternative to air conditioners.  Such areas in the U.S. include Colorado, Utah, New Mexico, Arizona, northern Texas, and some parts of California.  

Here are some advantages and disadvantages of using evaporative cooling vs. traditional, phase-change air conditioners.

Advantages of Evaporative Coolers:

  • Evaporative coolers are less expensive to install, estimated at about half the cost of refrigerated air conditioning. 
  • Operating costs are lower, as well.  Power consumption, limited only to the fan and water pump, is estimated at one-fourth of that used for air conditioning. 
  • Low maintenance is also an advantage of evaporative coolers because the only mechanical parts in most units are the fan motor and water pump, which can be easily replaced or repaired at low cost. 
  • Ventilation is increased due to the air being constantly cycled through the cooler to the interior and back outside through open windows and doors. 
  • The increased humidity content in the interior air that results from evaporative cooling can be desirable in dry climates. 
  • The cooling pads, when properly maintained, act to filter air, removing contaminants as the cooled air enters the interior.

Disadvantages of Evaporative Coolers:

  • High-humidity conditions will not allow the cooler to function effectively. 
  • Supplied air from the evaporative cooler is typically 80% to 90% relative humidity, which is sometimes not desirable for indoors, as it can accelerate corrosion, shortening the life of electronic and other equipment, and/or simple be uncomfortable. 
  • High humidity also causes condensation, which can become a problem with electrical equipment, old wood, paper and books, and develop into potential mold and mildew problems. 
  • Water must be constantly supplied to the pads.  Water that has a high mineral content will eventually leave deposits on the pads and the interior of the cooler.  The water supply line may also need to be protected from freezing and potentially bursting during the cold season. 
  • Odors and outdoor contaminants can be blown into the interior if sufficient filtering isn’t in place.  Asthma sufferers may need to avoid environments whose evaporative coolers are poorly maintained.

Evaporative coolers can be less expensive and environmentally friendlier alternatives to traditional air conditioners, depending on the climate and other factors.  Like any home system, homeowners should plan on becoming familiar with their evaporative cooler in order to maintain it seasonally.

Air-Conditioning Systems

A building’s central air-conditioning system must be periodically inspected and maintained in order to function properly. While an annual inspection performed by a trained professional is recommended, homeowners can do a lot of the work themselves by following the tips offered here.

Clean the Exterior Condenser Unit and Components

The exterior condenser unit is the large box located on the side of the house that’s designed to push heat from the indoors to the outdoors. Inside of the box are coils of pipe that are surrounded by thousands of thin metal “fins” that allow the coils more surface area to exchange heat. 

Follow these tips when cleaning the exterior condenser unit and its inner components — after turning off power to the unit, of course.

  • Remove any leaves, spider webs and other debris from the unit’s exterior. Trim foliage back several feet from the unit to ensure proper air flow.
  • Remove the cover grille to clean any debris from the unit’s interior. A garden hose can be helpful for this task.
  • Straighten any bent fins with a tool called a fin comb.
  • Add lubricating oil to the motor. Check your owner’s manual for specific instructions.
  • Clean the evaporator coil and condenser coil at least once a year.  When they collect dirt, they may not function properly.

Inspect the Condensate Drain Line

Condensate drain lines collect condensed water and drain it away from the unit.  They’re located on the side of the inside fan unit. Sometimes there are two drain lines—a primary drain line that’s built into the unit, and a secondary drain line that can drain if the first line becomes blocked. 

Homeowners can inspect the drain line by using the following tips, which take very little time and require no specialized tools:

  • Inspect the drain line for obstructions, such as algae and debris. If the line becomes blocked, water will back up into the drain pan and overflow, potentially causing a safety hazard or water damage to your home.
  • Make sure the hoses are secured and fit properly.

Clean the Air Filter

Air filters remove pollen, dust and other particles that would otherwise circulate indoors. Most filters are typically rectangular in shape and about 20 x 16 inches, and about 1 inch thick. They slide into the main ductwork near the inside fan unit. The filter should be periodically washed or replaced, depending on the manufacturer’s instructions. A dirty air filter will not only degrade the quality of the home’s indoor, but it will also strain the motor to work harder to move air through it, increasing energy costs and reducing energy efficiency. The filter should be replaced monthly during heavy use during the cooling seasons. You may need to change the filter more often if the air conditioner is in constant use, if any family members have respiratory problems, if you have pets with fur, and/or if it’s particularly dusty indoors.  

Cover the Exterior Unit

When the cooling season is over, you should cover the exterior condenser unit in preparation for winter. If it isn’t being used, why expose it to the elements? This measure will prevent ice, leaves and dirt from entering the unit, which can harm components and require additional maintenance in the spring. A cover can be purchased, or you can make one yourself by taping together plastic trash bags. Be sure to turn the unit off before covering it. 

Close the Air-Distribution Registers

Air-distribution registers are duct openings in ceilings, walls and floors where cold air enters the room. They should be closed after the cooling season ends in order to keep warm air from back-flowing out of the room during the warming season. Pests and dust will also be unable to enter the ducts during the winter if the registers are closed. These vents can typically be opened or closed with an adjacent lever or wheel.  Remember to open the registers in the spring before the cooling season starts.  Also, make sure they’re not blocked by drapes, carpeting or furniture.

In addition, homeowners should practice the following strategies in order to keep their central air-conditioning systems running properly:

  • Have the air-conditioning system inspected by a professional each year before the start of the cooling season.
  • Reduce stress on the air-conditioning system by enhancing your home’s energy efficiency. Switch from incandescent lights to compact fluorescents, for instance, which produce less heat.

Why Use a Trash Compactor?

Permanently installed residential trash compactors run on electricity and use a small hydraulic system to crush trash down to a fraction of its original volume (sometimes down to 25%) in order to reduce the amount of non-biodegradable waste regularly generated by a household. Smaller and narrower than a dishwasher, they are a standard kitchen appliance in new-construction homes.

How They Work

Trash compactors have three main components: the motor; the ram; and the trash container drawer. The motor runs using household electricity, which activates the ram that is operated using hydraulics. Units vary by size, quality and cost. The loading capacity for the average home unit is generally around 25 gallons, and the compacting force can range between 2,000 pounds to 5,000 pounds, depending on type and quality.

Most units must be at least half full in order to work properly. To use the unit, non-food refuse should be placed or stacked neatly at the bottom of the drawer. When it is at least half full, the unit can be activated so that the ram compacts the drawer’s contents.

Safely Disposing of Household Trash

Generally, bottles, cans, cardboard, paper and plastic items and the like can be conveniently disposed of in a trash compactor. In order to minimize odors, containers that once held food and beverages should be rinsed before being placed in the drawer.

Trash compactors require the use of specially-fitted bags that, once filled, easily lift out of the unit for disposal or trash pickup.

Perishable food items can stain the unit’s interior and create unnecessary mess and foul odors, which is why they should not be disposed of in a trash compactor. These types of items should be discarded using a garbage disposal or food grinder, or recycled as compost waste.

Additionally, hazardous materials should never be placed in a trash compactor, as crushing them can have unintended consequences that can damage the unit, create an unsafe environment, and/or cause negative health effects. These include batteries, cigarette butts (which may not be fully extinguished), household rags used with toxic substances, cans and containers that held hazardous liquids and chemicals (as residue can spill out and cause damage or negative health effects), and similar items. These should be wrapped and disposed of separately, or recycled according to local guidelines or ordinances.

Safety Precautions and Sensors

As a safety precaution, trash must never be stuffed down into the bottom of the drawer with one’s hands or feet, as this can dent or offset the drawer and its rollers, as well as damage the hydraulics. Rough use and frequent misuse can lead to chronic problems with the unit and its components.

Caution should be used when removing filled bags, as items that have been crushed may create sharp protrusions. Many people wear gloves while removing bags for disposal.

The unit should always be locked, even when not in use. Curious children may wish to pull open the drawer and hide inside, or activate the unit, which is why they should never be left unattended around an unlocked trash compactor.

Spills around the unit should be immediately cleaned up for safety as well as hygienic reasons. Because trash compactors use electricity, spilled water or other liquids can cause the unit to short out or create an unsafe hazard for users.

Trash compactors have built-in safeguards, such as locks, misload sensors, tilt sensors, and drawer-monitor switches, which are designed to help prevent injury, over-filling and under-filling, as well as detect when trash has been accidentally placed within the unit but outside the drawer (such as behind the drawer where the ram and hydraulics are located). However, because they are constructed of many mechanical parts and electrical wiring, trash compactors can malfunction and chronically break down if not used and maintained properly.
Repairs and replacing parts should be performed by a qualified professional.

What Are Food-Waste Disposers?

Garbage disposals, also called food-waste disposers, are residential appliances designed to shred food waste so that it can fit through plumbing. They are usually electrically powered (although occasionally powered by water pressure) and are installed beneath sinks.

Why Use a Garbage Disposal?

When food waste is discarded into the trash, it places an enormous burden on waste-management systems. Garbage disposals reduce the severity of these problems by routing food waste into septic systems or sewers instead of landfills.

Garbage Disposals and Septic Systems

If a garbage disposal discharges into a septic tank, it can place significant strain on the septic system. The amount of waste that enters the tank, particularly grease and suspended solids, will increase considerably. This load increase requires that the septic tank be pumped more often than would otherwise be required. The additional strain will also reduce the lifespan of the septic system. Septic systems can be designed to accommodate food waste, but, in general, they are not.

Electrical Wiring Requirements

The National Electrical Code (NEC) does not require a garbage disposal to have GFCI protection.
The vibration caused by the operation of a garbage disposal can cause electrical connections to separate. Check for any loose connections in the wire compartment box at the base of the disposal.
Garbage disposals should be either hardwired or connected to an outlet through a grounded electrical outlet.
A dedicated circuit is generally recommended, although a circuit that is shared with a dishwasher is sometimes appropriate. The disposal’s user or installation manual should be consulted.

Precautions for Testing Garbage Disposals:

To test a garbage disposal for leaks, turn it on and run water through it. The water load should be great enough so that any leaks will become apparent. A good way to do this is to close the drain and fill the sink with water before releasing the stopper.
While testing a garbage disposal, never put anything other than water through it. Before turning it on, check to make sure there are no objects already in the disposal.
If a dishwasher is connected to the disposal, make sure that the line that connects them is securely attached.
Check to make sure that the garbage disposal is connected to a drain that is 1½ inches or greater in diameter.
Check to make sure that the disposal is provided with an adequate water supply.
If the home has a double sink, check to make sure the waste pipe from the disposal has a trap installed.

Maintenance and Operation Suggestions:

Put only small quantities of food into the disposal at a time. Large food scraps should be cut into smaller pieces before entering the disposal.

Never put anything down the disposal that is not food or water. Bottle caps, aluminum foil, and other non-food items can damage the disposal or get stuck in the plumbing piping.
Run water while using the disposal and for approximately 30 seconds after you turn it off. Food scraps will flow through the piping more easily if they are pushed along by water. Cold water is better than warm water for this purpose because it will force fats and grease to congeal and harden, allowing them to move more easily through pipes. Warm water can be run through the disposal while it is not in operation.

Ice can be used to clear off solidified grease and other debris from the blades in a garbage disposal.
The garbage disposal should be used to grind only non-fibrous, leftover food. If in doubt as to whether something can be put in the disposal, err on the side of caution and put it in the trash instead.

The following items should never be put in a disposal:
items that are hard enough to dull the blades, such as shells from shellfish or bones;
food that is highly fibrous, such as corn husks, artichokes, pineapples, potato peels, asparagus, or celery, which should enter a disposal only in small quantities or disposed of in the trash. These foods take a long time to grind and can clog the disposal or the plumbing;
grease and household oils; or
chemicals.
Garbage disposals have the potential to limit the amount of household trash that must be taken away to waste management facilities. They can also place additional strain on septic systems and, for this reason, they should be used infrequently.

Under-Sink Plumbing

Sinks are a category of plumbing fixtures that includes kitchen sinks, service sinks, bar sinks, mop sinks and wash sinks. A sink is considered a different item than a lavatory (or a bathroom sink), although the terms are often used interchangeably. Sinks can be made of enameled cast-iron, vitreous china, stainless steel, porcelain-enameled formed steel, non-vitreous ceramic, and plastic materials.

Sink waste outlets should have a minimum diameter of 1-1/2 inches. Most kitchen sinks have an opening of 3-1/2 inches in diameter. A food-waste grinder has a standard opening of 3-1/2 inches, and so do most kitchen sink basket strainers. A strainer or crossbar should be provided to restrict the clear opening of the waste outlet.

Plumbing Requirements for Garbage Disposals

Food-waste grinders (also known as garbage disposals and disposers) are designed to grind foods, including bones, into small-sized bits that can flow through the drain line. Using them to dispose of fibrous and stringy foods, such as corn husks, celery, banana skins and onions, is not recommended because fibers tend to pass by the grinder teeth, move into the drain pipe, and cause drains to clog.

Water must be supplied to the grinder to assist during its operation in transporting waste. The water flushes the grinder chamber and carries the waste down the drainpipe. Blockage may result if the grinder is used without running the water during operation. Grinders should be connected to a drain of not less than 1-1/2 inches in diameter. Food-waste grinders are supplied with water from the sink faucet. They do not add to the load used to compute drainage pipe sizing. The drain size required for a grinder is consistent with that for a kitchen sink.

Plumbing Requirements for Dishwashers

The water supply to a residential dishwasher should be protected against backflow by an air gap or backflow preventer. The machine must be equipped with an integral backflow mechanism, or the potable water supply must have either a backflow preventer or an air gap. The discharge pipe from the dishwasher should be increased to a minimum of 3/4-inch in diameter. It should be connected with a wye fitting to the sink tailpiece. Before connecting to the sink tailpiece, the dishwasher waste line should rise and be securely fastened to the underside of the counter. The combined discharge from a sink, dishwasher, and waste grinder is allowed to discharge through a single 1-1/2-inch trap.

Maintenance Tips

Homeowners should take care not to overload the garbage disposal or the dishwasher, as this can lead to leaks and backups in the sink and the plumbing system. A backup at the kitchen sink may mean that the garbage disposal is clogged, or the plumbing line has some obstruction that prevents proper drainage. It’s important that homeowners understand the cause of the problem, as well as the proper way to repair it, before dismantling pipes under the sink. The right size of fittings and replacement parts, as well as proper drainage (including slope and traps) will ensure that the sink will work as it should following a repair, which is why most maintenance issues are best left to professionals, unless the homeowner has the proper instruction, parts and tools available.

How Does a Dishwasher Work?

Dishwashers are labor-saving and water-conserving appliances that were first invented in the U.S. in the 1850s. There are both portable units and permanently installed units that are found in most homes today.
Permanently installed dishwashers rely on the home’s electrical and plumbing systems, which is why their proper operation and maintenance are critical to household safety and trouble-free use.

A dishwasher operates with sprayed water using multiple cycles of washing and rinsing, followed by drying, using hot, forced circulated air. These cycles may be further distinguished according to length of cycle, power and temperature.

Dishwashers are plugged into a dedicated electrical receptacle at the back of the unit, and usually plumbed into the home’s hot water supply, although the cold water supply is also an option. This assures that the dishwasher’s load is optimally washed and rinsed using the maximum recommended temperature range of between 130° F and 170° F.

The dimensions of an average unit are 24×24 inches, although deluxe models may be wider and/or deeper to accommodate larger loads. Its interior components are typically made of stainless steel and/or plastic, and the exterior door may be metal, enamel-covered metal, or having a wood or wood-like veneer to match the decor of the kitchen cabinets.

Use, Maintenance and Precautions

Dishwasher-safe glasses, cups, plates, bowls, pots, pans and utensils, as well as some ceramic-ware and cutlery, are loaded into pull-out racks and baskets. They can be safely washed and rinsed in cycles that vary in intensity and length.

Many users rinse, soak or pre-treat cookware to remove solids and excess food waste before loading it in the dishwasher; this is a matter of personal preference, as well as how well the unit works on everyday and heavy-duty loads, although waste that cannot be adequately drained should be removed from dishware before the soiled items are loaded into the unit.

Dishwashers can also be used to effectively disinfect toothbrushes, infants’ plastic toys, formula bottles and synthetic nipples, and teething rings, as well as other household and personal hygiene items. However, extremely soiled items that come into contact with potentially hazardous or toxic materials, such as tools, gardening implements and the like, should not be washed in a dishwasher, as the toxic residue may not fully rinse out of the interior, which can contaminate future loads of dishware and utensils, as well as clog plumbing lines.

Soaps, pre-treaters and rinsing agents to prevent or eliminate water spots are available in a variety of costs, quality and effectiveness. They also come in both powder and liquid form. Regardless of the type of detergent used, it should be specifically for dishwasher use only, as other soaps can leave behind residue, as well as create excess foam and leaks.

Maintenance is relatively easy and can be done by running the unit through a hot-water cycle while it is empty, but this is only suggested following an especially dirty load where residue has not fully washed and drained for some reason.

Dishwashers should never be overloaded. Loads should be distributed and racked such that cleaning will be effective. It is recommended that plastic items be loaded into the unit’s top rack to avoid their coming into contact with hot elements in the unit’s bottom and then melting, or being jostled by the power of the sprayers and subsequently blocking them, which may prevent the water from reaching the unit’s entire load.

It is important to monitor the unit for failure to fully drain, as well as for leaks, excessive noise and movement, and burning smells, which can indicate a burned-out motor, an issue with the plumbing connected to the unit, or a problem with its original installation. A qualified professional should evaluate a malfunctioning unit and perform any repairs.

Water Heaters

A water heater is an appliance that heats potable water and supplies heated water to the home’s plumbing distribution system. Most tanks are insulated steel cylinders with an enamel coating on the inner surface. They are referred to as glass-lined tanks. The lining helps prevent corrosion. A water heater can literally explode if it’s not installed properly. There are standards that regulate the materials, design and installation of water heaters and their related safety devices. Certification marks on them from approved agencies indicate compliance with approved standards.

Conventional residential water heaters have life expectancies that vary greatly. The typical water heater has a lifespan of about 10 years, based on the following factors: correct installation; usage volume; construction quality; and maintenance.

Correct Installation

A water heater should generally be installed upright. Installing a water heater on its side will place structural stress on it due to inadequate support for the heater and its pipes, and may cause premature failure. Water heaters should be installed in well-ventilated areas — not just for fire safety requirements and nitrous-oxide buildup, but also because poor ventilation can shorten its lifespan. A water heater should also not be placed in an area susceptible to flood damage. Water can rust out the exterior and pipes, decreasing the life expectancy and efficiency of the unit. A water heater is best placed in an easily accessible area for maintenance. It should also be readily visible for fire and health-hazard requirements.

Usage

The life expectancy of the water heater depends a great deal on the volume of water used. Using large quantities of water means that the water heater will have to work harder to heat the water. In addition, the greater the volume of water, the greater the corrosive effect of the water will be on the tank materials, pipes, etc.

Construction Quality

As with most household systems and components, you get what you pay for in a water heater. Cheaper models will generally have a shorter lifespan, while more expensive models will generally last longer. A good indication of a water heater’s construction quality is its warranty. Longer warranties naturally imply sound construction. According to a 2007 Consumer Report that deconstructed 18 different models of water heaters, it was determined that models with longer warranties were of superior manufacturing quality, with nine- and 12-year models typically having larger or higher-wattage heating elements, as well as thicker insulation. Models with larger heating elements have a much better resistance to mineral buildup or scum.

Pay attention to the model’s features. For example, porcelain casing provides an additional layer of protection against rusting, and a greater level of heat insulation. Some models come with a self-cleaning feature that flushes the pipes of mineral deposit buildup, which can affect the unit’s lifespan. Models with larger or thicker anodes are better-equipped to fight corrosion.

Maintenance and Parts Replacement

The hardness of the water is another consideration when looking at estimating the lifespan of a water heater. In areas where there is a higher mineral content to the water, water heaters have shorter a lifespan than in other areas, as mineral buildup reduces the units’ efficiency. Even in areas where the water is softer, however, some mineral deposition is bound to occur. A way to counteract this mineral buildup is to periodically flush the water heater system, which not only removes some of the buildup, but, in tank systems, the process heats the water in the tank. Higher-end models typically come equipped with a self-flushing feature. In models for which manual flushing is required, it is important not to damage the water heater valve, which is usually made of plastic and is easy to break.

Although an older model may appear to be well-maintained, a question arises: Is the maintenance worth it? Warranties often exclude labor costs, so a good rule to follow is that if the total repair cost per year is greater than 10% of the cost of buying and installing a new water heater, it is probably not worth replacing any damaged parts.

Dishwasher Owners

Dishwasher Owners!!!! Recently I have been asked, “In your reports, why do you always mention that the dishwasher drain line does not have an air gap?” Here is why AND why everyone should verify correct installation ASAP. (And it likely won’t cost you a dime.) The dirty/grey water from your sink WILL drain into your clean dishwasher. Picture 1 – grey dishwater backing up into the dishwasher. Picture 2 – Less than a year old garbage disposal with an organic buildup flowing back into the dishwasher. Most dishwashers, depending on brand, won’t allow this size of organic material to pass through the screens. So the BLACK material is likely organic material from the sink/garbage disposal. Picture 3 – 10 yr old drain line with NO organic material because of proper installation. Picture 4 – Proper installation of dishwasher drain lines.