| Air conditioning is not just a luxury item for many | | | | how many hours a day it might actually run. The |
| houses anymore. When building a new house it is | | | | specifications provided by the manufacturer of |
| often included without question. There are so | | | | the unit you will use show the electrical usage of |
| many options when it comes to central air in a | | | | the unit. Take the watts per hour consumed by |
| house. The air conditioner BTU is a big thing to | | | | the unit, times the hours run time, divide by 1000 |
| consider. The efficiency of the air conditioner is | | | | and you will have the kilowatt hour of electric that |
| also a big factor to look at. Many new home | | | | the unit will consume. Now take that and times it |
| builders will include a builder model AC unit in the | | | | by the number of days a year the unit will run. |
| price of the house. If the homeowner wants to | | | | Then figure that times the cost of the electric |
| have a better, higher efficiency unit, they have to | | | | per kilowatt hour from your electric company. |
| pay extra for that. How much extra should they | | | | If with these numbers you find that your pay |
| pay and still come out with a good deal? | | | | back will be five years or less than I would for |
| There are a few things to check out when | | | | sure go with the higher efficiency unit. Keep in |
| upgrading the air conditioning unit. When buying the | | | | mind also that in some states the electricity costs |
| higher efficiency model it will usually include things | | | | are going to go up by 50% or more in the next |
| like high and low pressure cutout switches in the | | | | few years. You may want to run the numbers at |
| outdoor condenser unit. This can be very valuable | | | | those higher electricity costs. The farther south |
| and save the compressor from going bad if there | | | | you live, the more days you will use your air |
| is a problem. | | | | conditioning unit. Therefore it will be more |
| That could be worth the extra cost right there. | | | | beneficial to get a higher efficiency unit the |
| Also with a higher efficiency unit, the indoor air | | | | farther south you live. |
| handler will include a higher efficiency blower | | | | Heat Pump units often are rated much higher in |
| motor. The ECM motors will run much more | | | | efficiency that straight air conditioning units. |
| efficient then a regular motor. The efficiency is | | | | Especially in the mid to southern climates in may |
| even greater if the motor is run at low speeds | | | | pay to look at a heat pump unit. I will try to |
| much of the time. | | | | address that in the future. Heat Pumps will be a |
| The most confusing issue with any air conditioning | | | | whole separate subject. |
| is the SEER rating that the US Government uses | | | | So to wrap up the thoughts on air conditioning |
| to rate air conditioning units. The simplest formula | | | | efficiency. As electric prices rise the cost of the |
| I can use to explain this is that the SEER rating | | | | higher efficiency units will be much more practical. |
| compares the cooling BTU's that are made by the | | | | Higher efficiency air conditioners have more |
| unit per unit (KW) of electricity used. Usually | | | | safety controls built into them. You can do some |
| expressed as BTU's/Kilowatt of electric. Of | | | | figuring and find out how much more you can |
| course the more BTU's produce per kilowatt of | | | | spend for a higher efficiency unit and still get your |
| electric consumed the better off you are. | | | | money back in saved electricity. There are many |
| To arrive at a usage number you would have to | | | | good, better, best options out there. Ask your |
| figure up the number of hours per year that you | | | | contractor to quote the prices for the different |
| may be running the air conditioning unit. That can | | | | efficiency units available. If you do not ask usually |
| be done by taking the degree day information | | | | the prices will be the down and dirty lowest price |
| provided by the weather service for your area | | | | he can find unit. That rarely is a good thing. If |
| and through some fairly complex formula's coming | | | | your contractor does not want to quote prices on |
| up with usage for your house. I suggest that it | | | | higher efficiency units, then find one that will. You |
| may be much easier to just figure how many | | | | will not regret it. |
| days you will be running the air conditioner and | | | | |