Metro Heating and Cooling, Inc.


Click Here to go to our Secure Website:




Frequently Asked Questions About Evaporative Coolers

 How does an evaporative cooler work?  Evaporative coolers circulate water across pads or other media.  Air is blown across the pads, evaporating the water.  This evaporation is a cooling process, cooling the air as it enters your house.  Properly designed, a cooler will lightly pressurize the house with cool fresh air.  The cooling will go to the areas where you ventilate, such as open windows, doors, up-dux or other vents.  Ventilation and proper sizing are critical to the proper operation of your cooler.

 How much will a cooler cool my house?  Different coolers have different cooling capacities and efficiencies.  There is a mathematical equation based on the outside air temperature, dew point and pad design that will give an exact answer.  With the Breezair cooler installed, you should be able to maintain a comfort level of about 74 to 78 degrees under the worst of summer conditions, and be able to make it cold enough to need a jacket under ideal conditions.  As the humidity outside increases, the cooling efficiency is reduced.  Evaporative coolers are usually used where the relative humidity is less than 50 percent.  The drier the outside air is, the cooler the discharge air will be.

 How do you hook the cooler up to the water?  When we install a cooler, we prefer to run all of the water lines on the outside of your house to prevent any damage that may occur if the water line has a leak.  We usually use a piggy-back style hose bib that will attach to your existing hose bib.  This piggy-back bib will allow the cooler to maintain proper water levels as well as allow you to still use the hose.  Important note: Some sillcocks or hose bibs will drip water from the packing nut at the handle stem after the water is turned on.  Usually, the packing nut can be tightened to eliminate this type of drip.  If tightening the valve packing doesn't cure the drip, a new hose bib may need to be installed.  This is not a cooler or warranty problem, it is a problem with worn or deteriorated valve packing inside your hose bib.  Most of the time, the problem is not apparent when the water is turned off.  In some cases, the water may be connected to a sprinkler system manifold.  Water can also come from connections to the interior plumbing of the house.  We do not recommend any cooler water line be run inside of any building.  We have a disclaimer that removes any liability from us in the event of any leak from a waterline installed inside of any structure.  If your waterline is hooked up under a sink, we will not service your cooler.

 How much water do they use?  Coolers evaporate water to provide cooling.  The water usage is dependent upon cooler size, operating speed, cooler design, comfort level desired and outside conditions.  Most coolers typically use 40 to 60 gallons of water each day during the season.  Water managers, auto drains and clean machines can increase this usage somewhat.

 How many windows do I need open?  In most cases, if you open every window and door wide open your cooler will just work better.  You can balance the cooling by adjusting your windows. Areas that you want cooler, open the windows more.  Areas where you need less cooling, open the windows less.  High indoor humidity is usually because of inadequate ventilation.  The more you ventilate, the better your cooler will work and the indoor humidity will be lower.  You need at least 1 square foot of screened ventilation opening for every 500 Cfm of airflow your cooler will deliver.  A 5000 Cfm cooler will need at least 10 square feet of screened window openings, usually spread around the home to balance the cooling.

 Are there any problems with humidity?  Humidity is increased due to the evaporation of the water into the air stream as the cooler is working.  Proper ventilation is necessary to keep humidity levels within acceptable ranges.  In cases where the ventilation is inadequate, humidity levels can approach 100%, possibly causing humidity related problems.  See the question about window opening above.  See the question about humidity controllers below in the humidifier section.

 How long does it take to install a cooler?  Most installations are completed in 1 to 2 days.  When we need to coordinate with another contractor (like your roofer, for example), the jobs usually take longer.

Are permits required?  Most replacements and new installations will require a permit.  We permit everything!  When your job is completed our office will coordinate all necessary inspections with you.  It is your responsibility to meet with the inspector(s) and provide access.

Do swamp coolers leak when itís raining?  Properly installed coolers will not leak rain or snow.

I plan to replace my roof.  Should I get it done first or the cooler done first?  It depends.  If you plan to use tile, metal or plastic roofing you should probably consult the roofer to make sure anyone should ever be on your roof or not.  We will probably need to work together to get the jobs done.  We usually like to get standard shingle style roofs done before we install a new cooler.  The are many reasons.  If the roof needs decking replaced, the cooler and roof flashing may need to be removed to replace decking.  The same applies to multi layer shingles.  We permit everything.  Our step and counter flashings are custom cut and bent in our sheet metal shop, not bent over your sidewalk or something.  The water and drain lines are in the way of the roofers and are often broken off during the roofing process.  We spend a lot of time running the lines neat and straight.  The drains on the cooler are often broken off.  The legs on every cooler we sell are adjustable but they are often bent or broken off instead of properly fastening and leveling the cooler.  We warranty our roof work against leaking but the roofers usually exclude all leaks from the cooler.  We respect your roof.  We will take all of the usual precautions to protect it whether it is new or 40 years old.  I don't want to sound too negative.  Many of the cooler installations we have seen are done so poorly that the roofers never had a chance.  The installation process we follow will allow roof replacement without needing to remove the cooler unless there are decking replacement issues, etc.

 What are some of the guidelines for installations and change outs of roof mount coolers?  Most jurisdictions require a building permit to install or change a roof mount cooler.  There can be as many as three permits involved...a roofing permit, a mechanical permit and an electrical permit are common.  The following are the most common things we see done incorrectly on existing coolers.  Many of these existing coolers were originally installed before there was much concern about codes or permits.  There is little or no "grandfathering" allowed, the building inspectors will require you to bring things up to current code.  These codes are for your safety and protection, for the most part.

         Evaporative coolers need to be installed at least 10 feet from fireplace, furnace and hot water flues or chimneys to minimize the possibility of the cooler circulating products of combustion, like carbon monoxide, throughout the house.  The same 10 foot rule applies to drain/waste vents.  When the 10 foot rule cannot be maintained, the vents, etc. must be extended 3 feet above the top of the cooler.   You must also have carbon monoxide detectors as required by code.  CO detectors are your responsibility.  You may not pass an inspection without them.

         Evaporative coolers need to be properly attached to the roof and duct system.  Legs, when required, cannot be fastened to the ridge or valleys where sheet metal troughs may be damaged by nails, etc.  The duct penetration must be properly sealed to the roof.  Tar is not an approved method and will not pass an inspection (tar and gravel roofs are a qualified exception).

         There needs to be 12 inches clearance between the bottom of the cooler and the closest point to the roof (at the top).

         If there is a skirt or curb, it must be usually be removed.  Most curbs are improperly sized and improperly sealed for most residential applications.  Drain access is usually a problem also.  Skirts are allowed only when they are not flashed or otherwise attached to the roof.  If they are attached only to the legs, they may not be a problem.  If they are flashed or tarred to the roof, roofing repairs will probably be needed to pass inspection.

         Step roofs may require roof safety kits as a minimum, and may require a 30" wide catwalk with a guard rail in some jurisdictions.

         Ductwork must be properly sealed and insulated.

         The cooler must be on a dedicated circuit, meaning having it's own circuit breaker labeled in the electric panel with nothing else on that circuit.  The wires from the cooler, breaker and thermostat must be of the proper size and type.  Everything must be grounded.  Wires run inside of the duct are not allowed unless the wire is plenum rated.  Some electric panels may need to be updated to meet current code.

         There needs to be an acceptable location to hook up the water.  Leaking hose bibs are not a cooler or warranty problem.

         Tree limbs may need to be removed to allow adequate clearance for the cooler to operate properly and for access to install or service the cooler.

 When is the best  time to start up or shut down my cooler?   We live in an area that can be unpredictable as far as weather is concerned.  Usually, coolers are safe to be started up in early May, the 5th to the 12th, and should be shut down before freeze danger, usually by the end of September.  You should be familiar with the shut-down instructions so you can help protect everything in the event we have an unexpected freeze while your cooler is still hooked up.  Freezing is not a warranty problem.  Important;  During the peak of start-up or shut-down season, service is strictly limited to our previous installation customers, on a first come/first serve basis. These services need to be scheduled a minimum of 6 weeks in advance.

  How do I schedule a start-up or shut-down on my cooler?  Cooler start-ups and shut-downs can be scheduled by calling our office during normal business hours.  We maintain a database of previous customers as well as service contract holders.  We recommend your service be scheduled early in the season.  If you schedule your service early, you will have more flexibility with times and dates.  During the start-up and shut down seasons, many people wait until the last minute.  During our peak times, cooler contract customers will receive the highest priority.  Non-contract customers will often experience waiting periods during these times approaching a month or more.  Important:  Service is strictly limited to our previous installation customers, on a first come/first serve basis.

 Do I need to cover my cooler in the winter?  BreezAir coolers as well as standard metal coolers should be covered in the winter to help prevent heat loss through the duct and cooler.  AeroCool coolers use a winterizer panel that replaces the cover.  Covers are available for most coolers.

 What do I need to know about servicing my cooler?  Evaporative coolers require routine service including, but not limited to, spring start-up and fall shut-down.  Since evaporative coolers have water in them, they should be shut down and winterized each fall to prevent freeze damage to the cooler, water line and house plumbing.  During the shut down service, the cooler should have the drain removed and the waterline disconnected at each end and blown out to remove any remaining water in the line.  The cooler should be rinsed and flushed to remove any leaves, cottonwood lint, etc. as well as minerals which may have accumulated due to the evaporation of water.  The block off plates or cover should be installed and the indoor diffuser or vent(s) should be closed to prevent heat loss from the house.  The blower drive belt should be removed to prevent it from becoming egg shaped during the long winter off cycle.  If these things are done in time each year, the cooler will be prepared for next springís start-up.  The spring start-up will require the drain to be reinstalled, the water line reconnected and checked for leaks, the belt to be reinstalled and adjusted properly, the block off plates to be removed and the indoor diffuser or vent to be opened.  These services are required for the proper operation of your cooler and the homeowner can usually accomplishes them.  We offer the start-up service and shut-down service on a per visit basis.

How do I shut down my cooler for the winter?  See the "How to Shut Down your Cooler" link on the Cooler Shutdown page for some detailed information.

 What is the difference between line voltage control and low voltage control?  Line voltage is the voltage that is present on most of the plugs in your house...110-120 volts.  All coolers require a line voltage connection, usually a single 20 amp circuit.  Most coolers are available as 2 speed coolers supporting line voltage control.  A six position switch is the standard control method, some line voltage thermostats are available to provide more automatic control.  (off, hi cool, low cool, hi vent, lo vent and pump only are the six positions).  As stated above, all coolers require a circuit to the cooler as a minimum.  With line voltage control, six wires should then be run through the attic, down inside a wall, have a box cut into the wall, have the wires terminated in that box to your switch or thermostat.  By comparison, low voltage control still requires the same 20 amp circuit to the cooler.  Then a control box allows low voltage thermostat wiring to be run to a good place for the thermostat.  Electricians must perform the line voltage connections at your expense, we run our low voltage thermostat wire and mount the thermostat with low voltage control as part of our installation.  Most of the low voltage packages are superior in their performance to line voltage packages because they support prewet cycles, automatic speed selection and tighter temperature control.  In some cases, line voltage makes sense but most of the time the low voltage control is superior and costs less to install after additional electrical costs are included.  You must also have carbon monoxide detectors as required by code.  CO detectors are your responsibility.  You may not pass an inspection without htem.

What is the difference between  the 2 speed and the variable speed BreezAir?  The BreezAir Elite series cooler is available as a line voltage or low voltage 2 speed cooler as described above.  Your cooler will operate on either high or low speed.  The BreezAir Elite series is also available with a low voltage control package that has either a wireless remote or wall mounted thermostat.  The SensorTouch Variable Speed Controller will automatically turn your cooler on, matching the motor speed to the conditions, so your cooler keeps you in the comfort zone you set on your thermostat.  As your house warms up the cooler will speed up.  As your home cools off it will slow down.  While you sleep, the cooler will slow to a very soft, quiet level, keeping you comfortable with cool fresh air.  If cooling is not needed, the cooler will switch to ventilation mode, bringing in a bit of fresh air.  If it gets too cold, the cooler will switch off, waiting to do it all over again.  The variable speed SensorTouch operation is a BreezAir exclusive and is another reason they are the best cooler in the world.  The  EXV series as well as the Icon series and TBA commercial coolers support variable speed control as well as factory installed Water Manager and AutoDrain systems.

Where I live, roof mounted equipment is not allowed due to covenant restrictions.  What can I do?  We have coolers in various configurations, other than roof mount.  We have side discharge coolers than can be installed through the side of the house, as well as window mount and portable coolers.  We have performed some exotic installations to appease some associations' rules.  Such installations can provide cooling that is comparable to roof mount coolers.

 What is a water manager, auto drain or clean machine?  As water is evaporated from your cooler, the minerals in the water are not evaporated.  When the mineral content reaches the point of crystallization, deposits will build up on your cooler, reducing efficiency.  The water manager or clean machine will replace the mineral laden water before the deposits develop, keeping your cooler clean and operating properly.  An auto drain is a Breezair option that is designed to allow the cooler to remain drained and dry during long off cycles.  Having the cooler drained regularly will keep your cooler cleaner, operating better, lasting longer and smelling better.  The auto drain is not freeze protection. 

Frequently Asked Questions About Air Conditioners

 What is a ton?  A ton of cooling is 12,000 Btu.  A two ton system will have a cooling capacity of 24,000 Btu., a three ton system 36,000 Btu., etc.  Each ton of cooling requires 400 cfm. of air flow.

 Do air conditioners still use freon?  Freon is a brand name commonly used to refer to a wide range of refrigerants.  Refrigerants are what make mechanical cooling possible.  They are not interchangeable.  Various refrigerants have been phased out by the timeline established by the Montreal Protocol in 1987.  This is an international treaty to try to control ozone depletion in the earth's atmosphere.  Most of the air conditioner systems installed since 1970 have used a refrigerant labeled R-22, commonly wrongly called Freon.  Automobiles and refrigerators used refrigerants such as R-11 and R-12 for years.  Refrigerants R-11 and  R-12 have been or are currently in phase out, due to their high ozone depletion potential. R-22 has a relatively low ozone depletion potential.  The manufacture of equipment and products using refrigerant R-22 will cease in the year 2010.  R-22 refrigerant production will end in the year 2020.  Supplies of R-22 will become scarce around or after the year 2030.  Alternate refrigerants have been introduced such as R-410A in 1997.  Those residential A/C systems were reengineered to use the new, environmentally friendly R410a refrigerant. Now, that is being phased out. Evaporative coolers use none of those environmentally unsound chemicals, just fresh, clean water.

 How often do I need to add Freon?  Hopefully, never.  Once the system is properly charged with refrigerant during installation, the system should remain closed and leak free.  If you need to add refrigerant from time to time, there is a leak that must be repaired.  Topping off a leaking system is against the law in almost every case.  You must be licensed by the city and/or state as well as the EPA to handle refrigerants.  Specialized recovery equipment is required

 Should I get a bigger air conditioner?  A properly sized air conditioner will perform better than one that is oversized.  Blower size, duct work design and heat load are very important to properly size a system.  Usually, you are better served to have the system slightly undersized than oversized.  Over sizing may lead to freezing of the indoor coil, causing a great loss of comfort and efficiency as well as possible system

 Do I need a special furnace for A/C?  Most of the furnaces manufactured today are air conditioning ready, meaning they have a multi-speed blower motor and built in relays and terminal strips to accommodate A/C.  Older furnaces may need upgrading to accommodate air conditioning.

 How do I take care of my air conditioner?  The two things to remember about air conditioning are (1.) Airflow is all important and (2.) How important it is to be kept clean.  The air filter installed in your furnace also cleans the air for your air conditioner.  Filter maintenance is critical to allow proper airflow to the cooling coil.  High performance filters are a good idea.  Many electrostatic filters are too restrictive after a very short use time and their use is discouraged during the cooling season.  A dirty filter may cause enough loss of airflow to lead to freezing of the indoor coil.  The indoor coil will need to be cleaned from time to time to eliminate dirt build up on the coil.  The condensate drain should be kept clear and the floor drain or condensate pump should work to prevent flood or water damage.  The outdoor unit should be cleaned from time to time to remove leaves, vines, cottonwood lint, etc. and so maintain reliable, efficient operation.  Typically, the unit should not be covered during the winter months.  If you have a humidifier installed, it should be turned off during the cooling season.  If you have a bypass humidifier, the bypass must be closed during a/c use or freeze-up may be a problem.  We currently limit air conditioning repairs to systems we installed or are maintaining service contracts on.  Routine cleaning and servicing of A/C systems may be scheduled during off peak times.


 Furnaces and Heating

 Do these newer furnaces have pilot lights?  Most of the furnaces built today do not have a pilot light that stays lit all the time.  Spark ignitions and hot surface ignitions have eliminated the standing pilot in an effort to meet federal efficiency standards.  The newer systems operate well when they are properly maintained.

  Should I get a bigger furnace than I have now?  Probably not, if your old furnace properly heated your home.  Most of the older furnaces installed in homes in the metro area are already oversized.  If the existing furnace is older than 15 years, the newer furnaces with their higher efficiency standards can typically be downsized to take advantage of this efficiency advantage.  A properly sized furnace will last longer than one that is oversized.

 I have air conditioning or I plan on adding air conditioning...Do I need a special furnace for A/C?  Most of the furnaces manufactured today are air conditioning ready, meaning they have a multi-speed blower motor and built in relays and terminal strips to accommodate A/C.

 What is the big difference between 80% efficiency and 90+ efficiency furnaces?  Most manufacturers build furnaces in two general configurations, 80% (non-condensing) and 90+% (condensing) efficiency.  The 80% efficiency standard is the minimum federal standard for residential heating equipment.  Flue gasses contain many compounds such as carbon dioxide, carbon monoxide, sulfuric and nitric acids.  What the flue gas has the most of, though, is water in the form of steam.  The 80% efficiency furnace is designed to prevent condensation when it is properly installed.  Most furnace systems are common vented with the home's water heater.  Most water heaters are non-condensing under normal conditions.  When common venting is required or when the existing metal venting is to be reused, the 80% configuration is most commonly used.  Condensing furnaces (90%+ efficiency) extract almost all of the heat from the exhaust.  As more heat is removed from the flue gasses, the products of combustion are cooled to the point that condensation occurs.  The condensate is caustic to untreated metal, ceramic, brick, mortar and concrete.  The venting systems need to be specially constructed to deal with the caustic nature of the condensate, usually of, believe it or not, PVC plastic pipe.  Most homes can be readily modified to take advantage of the 90%+ efficiency models, but not in all cases.  Sometimes, the 90+ is the best and least expensive option, but sometimes the 80% configuration is the least expensive choice for retrofit situations.  Rebates and tax credits can really influence the choice you may make.

 Since these newer furnaces don't have pilot lights, they must be almost maintenance free, right?  Unfortunately, the newer furnaces require more than just changing the filter every now and then.  These newer furnaces have more circuitry and moving parts than the old ones.  This complication increases with the advances in efficiency of the newer furnaces.  Most of the manufacturers as well as most of the gas suppliers recommend furnace heating equipment be cleaned, serviced and adjusted on an annual basis.  If this service is neglected, you can plan on a service call.  Annual cleaning, service and adjustment will help ensure safe, clean, reliable and efficient operation.

 I change my filter at the beginning of every winter.  Is that often enough?   Maybe, if you have one of the high performance filters.  Some high performance filters are designed to need yearly service, some are designed to be serviced at the beginning of each heating and cooling season.  If you are using the less expensive poly fiber filters or an electrostatic filter, you should service the filter every month.

 What should I know about my furnace?  Obviously, you should know where it is, like in the basement, crawl space, attic, closet, etc.  You should know how to turn on the light and make sure the bulb works.  You should know how to turn off the electricity to the furnace, both at the furnace room and also at the circuit breaker in your electric panel.  You should know where to turn off the gas to your furnace as well as any other appliances in your home.  You should know where your electric panel and gas meter are located.  You should know where the filter is located.  You should know the make, model, serial number, warranty status and approximate age of your furnace.  You need to be aware of the service requirements of your furnace, air conditioner, air cleaner and humidifier.  You need to know how to operate your thermostat and change the batteries as needed.  You should have the telephone number to your gas and electric supplier. 

Humidifier and other Accessories FAQ's

 What are the system requirements for humidifiers?  Humidifiers require a water source nearby.  There must be a drain near by or in the absence of a suitable drain, a condensate pump needs to be installed.  There must be an electrical outlet nearby for powered models.  There needs to be adequate room on the ductwork for the humidifier to mount, or modifications may need to be made to your ductwork.  If you are using air conditioning, a relay may need to be added to your furnace for proper humidifier use.

 Can you install humidifiers in attics or crawl spaces?  Yes, as long as water lines and drains are freeze protected and the other system requirements are met.  Freeze protection may be easy to accomplish or may not be so easy, depending on the circumstances.

  How do I care for my humidifier?  The humidifier needs to be cleaned on an annual basis in most cases.  The pad or evaporation media needs to be removed and flushed with hot water to remove mineral deposits left behind by the evaporated water.  Presoaking in a water and vinegar solution will help to loosen deposits.  If the pads are beginning to deteriorate, they should be replaced.  Honeywell recommends media replacement on a yearly basis for the best anti-microbial treatment.  Pads are readily available through our service department.

 Why does my humidity controller have different settings based on outside temperature?  As it gets colder outside, the windows in the home have more opportunity to develop fogging or frosting.  Resetting the humidity set point inside your house will reduce or eliminate this fogging.  The suggestions on the humidity control are just that, suggestions.  With some trial and error, a permanent setting can usually be found that allows comfort as well as no frosting.  In most cases, if the home has more modern windows, this frosting isn't a problem.  Setting the humidity level too high may cause condensate to build inside attics, inside the roof and inside attic mounted duct.  As outside temperatures fall, the humidity levels need to be reset to prevent condensation.  Some of the humidifiers we install have an outdoor air sensor that automatically reset the levels.

 How often do I need to clean the filters in my electronic air cleaner?  The pre-filters and filter cells should be washed in the sink, or better yet, run through the dishwasher every 3 months...more often if you have high dust from remodeling or shedding pets, etc.

 How often do I need to change the filter in my Honeywell high performance media filter?  You should replace the filter media once a year or when the "Air Watch" indicator lights.

 How long do the Ultraviolet bulbs last in my germ killing lamps?  The newer bulb designs are a considerable improvement over the old ones, which lasted about a year.  The newer ones last as long as 5 years or more.












Home ]

Send mail to with questions or comments about this web site.
Copyright © 2007 Metro Heating and Cooling, Inc.
Last modified: 04/21/24