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Please let the information below, remind you to stay cool and keep your A/C running at peak

performance.

The following is information you should know and use to help assure that your Air-conditioning

is keeping you as cool as possible and working and cooling as efficiently as possible, saving you

money. The following should help you decide if you need a professional to service your Air-conditioning unit.

(1) Air filter(s) MUST be clean. They should be located near the return air duct adjacent to the

air handler or in a return air grill(s). Check your air filter every 30 to 90 days to make sure it is

clean. Depending of the house, i.e. if you have animals you may need to clean the air filter moreoften. (Go clean them now!)

(2) Flip the switch on the thermostat for the fan setting to FAN ON, not AUTO. This will run the

indoor fan nonstop. The outside A/C unit will still cycle with a call for cooling from thethermostat. The constant air moving will keep you cooler. You can probably keep the thermostat

a degree or two higher than normal and still feel comfortable. You will also maintain a moreeven temperature between upstairs and downstairs. This will SAVE you MONEY because theoutdoor condenser will not come on as much!

(3) Make sure that you wash the outside condenser coil once a year. If it's dirty, the A/C will runhot and inefficient. A sign of the coil being dirty is the small exposed copper (pipe) (tubing) line,

usually 3/8" O/D connecting the inside unit with the outside unit will be HOT to the touch.

(4) If the small exposed 3/8" copper pipe connecting the inside unit with the outside unit is hot to

the touch there can be several reasons why;

(a)

A/C is low on refrigerant.(b) The outdoor condenser coil is dirty. Those are the two most common reasons for it to be hot

to the touch.

(5) "Warm Rooms" on the lower levels of the house where it is cooler cut back or cut off somevent registers (Diffuser) and make sure that all the ones on the upper floors where it is warmer

are open all the way! Also, see paragraphs #2 & #9.

(6) "Doors" if you close the door to a room make sure that there is about a 3/4" gap between the

bottom of the door and the floor. You may have had carpet put down on the floor and now there

is no gap. This is necessary if you have a central return air duct in the hallway. The return air

ducts need to pull the warm air from the room.

(7) Never leave the house and turn OFF the A/C. then come back home and turn it on and expect

it to cool the house anytime soon. Doing this will not allow the unit to cool down the house forseveral hours. You can set the temperature up five to ten degrees but NOT OFF. This is because

of Latent heat buildup in the walls and furniture in the house and will make the A/C work harder

to remove the heat, this takes a long time.

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(8) Never turn the A/C off than back on in less than five minutes, this will short-cycle the

compressor and can trip breakers, blow fuses, or cause permanent damage the compressor. Youshould have a time-delay install on the A/C to prevent this during power outages! Some setback

thermostats have a time-delay built-in. Having a start capacitor and relay is a good idea. This will

increase the life expectancy of the compressor by starting faster thus keeping motor temperature

down, using less electric to start.

(9) Keep blinds closed, curtains drawn, window shades drawn, a working attic fan would be agood idea, plenty of insulation in the ceiling & walls, air tight storm windows, keep outside

doors and openings close, etc.

(10) "Icing of the indoor coil or the large insulated covered copper pipe "There are two main

reasons for this, lack of air flow or low on refrigerant. Lack of air flow can be a dirty air filter,

dirty indoor evaporator coil, dirty fan blades, damper in duct restricting air flow.

(11) "Water inside around air-handler" see paragraph 10. The condensate line is a drain pipe

coming from the indoor evaporator coil to a indoor drain or to the outside. This can becomeclogged and cause water to backup and can produce about five gallons of water an hour. This is

where all the humidity and moisture from the house goes.

(12) You should NEVER need to add refrigerant to a system, if you are adding refrigerant this

means that there is a refrigerant leak in the system that SHOULD be fixed! "Why KILL theOzone layer?"

(13) Checking the cooling with a thermometer. There should be a 15-20 degree temperature drop

across the indoor coil at the air handler. Check the temperature drop in the duct close to the coil,if air coming into the coil is 75 degrees than the air leaving the coil should be 60-55 degrees. If it

is higher or lower there is probably something wrong. Too high of a drop, IE more than 20degrees drop, could mean lack of air flow or low on refrigerant. Less than a 15-degree drop

could mean too much air flow, dirty outside coil or low on refrigerant.

(14) Never cover the A/C with plastic or an air tight cover; this will cause it to rust.

(15) Do NOT let animals (Cats) (Dogs) etc. Urinate on the outside coil. This will cause it to

corrode (rust) and then leak refrigerant.

(16) Keep grass & weeds from blocking air flow on outside A/C.

(17) Do NOT build a deck close to the top of the outside A/C or anything else that could causethe warm discharge air to re-circulate back to the unit.

(18) Fuses, Circuit Breakers or wires should never be hot to the touch; if they are hot you may

have a sizing problem or a loose or bad electrical connection.

(19) You can stop hear, the rest may not interest you.

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When you need to have your equipment repaired/serviced make sure you use a licensed

contractor who should be insured and obtain permits from city/county officials whenrequired/necessary. Or a member of the (PHCC) Plumbing, Heating, Cooling Contractors

Association. PHCC contractors are professionals who adhere to a published code of ethics that

improves the industry and protects your health, certified by the State Board of Contractors. They

also have licenses, bonds, insurance and obtain permits when required by local municipalities.The PHCC logo is your assurance of quality in this profession! Isn't your health & safety worth

it? It should be! Call 1-800-533-7694 for more information about the PHCC.

Air-Conditioners DO NOT add cool air. What they do is remove warm air and put it outside. R-

22 & R-12 ETC.. Refrigerant is a manmade product invented by DuPont and given the tradename FREON.

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The temperature of refrigerant is directly relate to the pressure it is at and vise versa, IE.R-22 at 0psi is -40 degrees below zero or at 60 psi it at 32 degrees. This is misleading; the temperature

change is NOT related to pressure really, but almost totally tied to the change from a liquid to agas. When liquid Freon is expanded to a gas it gets really cold (latent heat of evaporation) andwhen the warm gas is compressed to a liquid it get hot. The temperature change in say

compressing liquid Freon to a higher pressure (adiabatic compression) is small. You see the

same effect when you crack the valve on a CO2 (or propane) bottle for example. You will get asmaller effect with a pure gas, like when you fill a Scuba tank, (gets warm) or drain it quickly

(valve gets cold right at the expansion point, but this effect is not great enough to run an AC

system.

The physics of phase change from a gas to a liquid and vice versa drive most weather for

example as well.... With water it takes as (I recall) 560 (or was it 590...) times as much energy to

boil water from 100 C liquid to 100C gas as it does to raise the same amount of water 1C intemperature. Freon is less dramatic than water in terms of this energy amount, but it boils at a

much more convenient temperature for human AC units than does water. If you wanted the

inside of your house to be 100C you might want to run water in your AC.

FYI only.

*****************************************************Keep in mind that heat goes toward cold and not cool to heat. All the A/C compressor does is to

pump vapor to create a high and low pressure, IE. A low pressure at the inside coil for a low

temperature for the refrigerant to absorb the heat in the house and a high pressure at the outside

coil to give off the heat the refrigerant absorbed from the inside coil to outside. Over sized A/Cwill run short cycles and not remove the humidity and moisture from the house, an under sized

unit will not be able to keep the house cool on a hot day. You MUST be careful to get the correct

size A/C for your house. A/C's are sized by tons; there are 12,000 BTU'S to a ton of cooling.("Ton" means 12,000 BTU'S of heat is needed to melt one 1 ton (2,000 Pounds of ice) You need

to move 400 CFM of air per ton of cooling across the indoor coil. 450 CFM for Heat Pumps.

Each CFM (Cubic foot per minute) of air will carry 26.7 BTU's of cooling. You need a heat-gaincalculation done per room to get the proper (CFM/BTUs) to be delivered to each room and the

total (Tons/BTUs) needed to cool the house based on designed weather conditions in your area.

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