Newsletters From The Desk of Cathy

Welcome to our first edition of our Frequently Asked Questions Newsletter.

Question #1: Why are bigger filters better than the smaller ones?

Straightforward Answer:

A filter with a larger surface area will lower the speed of the air passing through it; as a result the dirt is more likely to stick to the filter media.

Technical Answer:

The Air Conditioning System has a design pressure for optimum performance. If filter exceeds the design pressure for the system then airflow will be reduced and so will system overall efficiency. The air will be better filtered BUT will have more moisture in it. Proper installation requires measuring pressures in the system to ensure proper operation of the entire A/C System.

Question #2: Why is my electric bill so high?

Straightforward Answer:

Your electric bill is a reflection of power consumed. Most common reasons are:

• The efficiency of some appliances has gone down over time (like gas mileage of your automobile with age.)
• Cost of power has gone up
• A combination of both

You can check for some normal causes through the following:

1. Does it take longer to dry clothes than it use to?
a.) Could be caused by a blockage in the exhaust ducts.

2. Does central heat & air run more or feel less comfortable than last year?
a.) Is unit still blowing the designed amount of air
b.) Is unit working at capacity
c.) Is duct system & filtration sized for system design criteria

3. Check your FPL bill for the section that says “ENERGY USAGE” ie: KWH - last year - this year, and see if usage has increased or if the cost has increased.

STRIVING TO SERVE YOU BETTER

• Pre-employment testing – before hiring.
• Random drug testing – optional to employer.
• Of course post accident drug testing – after an injury on the job.

We felt this was insufficient to provide the level of Safety & Security we require for your peace of mind, so we have chosen to go the extra mile and do routine drug testing. We are also certified in Air Balancing & HVAC System Diagnostics.

I hope you find this newsletter educational and we look forward to your continued participation. So, keep sending me your questions!

Sincerely,
Cathy

FIRST CLASS FAQ NEWSLETTER
2nd EDITION

Question #1: What does it mean if I have a 2.5 ton A/C system?

Straight Forward Answer:

The tonnage of your unit determines how much heat is going through your system per hour.
A single ‘B.T.U.’ = (British Thermal Unit) is about the heat produced by one match.
12,000 BTU’s per ton per hour – a 2.5 ton unit would have about 30,000 BTU’s per hour.

Technical Answer:

1 ton of refrigeration is equal to the amount of heat required to melt 1 ton of ice in 24 hours.
1 ton of ice = 2,000lbs
Heat to melt 1lb of ice = 144 BTU per lb
288,000 BTU per day is 12,000 BTU’s per hour

BTU: British Thermal Unit
Quantity of heat required to raise the temperature of one pound of water one degree Fahrenheit.

Question #2: What is the normal CFM for my 2.5ton A/C unit?

Straight Forward Answer:
The average is 400 CFM per ton which is about 1,000 cubic feet per minute for your 2.5ton unit.

CFM = Cubic Feet per Minute
A cubic foot is the space inside of an area that is 1 foot wide, 1 foot deep, & 1 foot high

Technical Answer:

The amount of air is affected by many variables. The blower of your Air Conditioner is designed for Flow (CFM) for a given tonnage. However, if the duct system is too small (too resistant) the blower will produce less air flow. The unit capacity is directly related to this air flow.

Example: a 3ton unit should have about 1200 CFM. If air flow is reduced to half then the unit will produce about half of its capacity.

For more information on this you can go to www.nationalcomfortinstitute.com

Don’t forget to send me your questions!!

FIRST CLASS FAQ NEWSLETTER
3rd EDITION

Today’s question is on Thermostats. I for one have always been under the misconception that when you turn the T-stat from 75 down to 65, the air that comes out is colder. In reality, the Thermostat is an OFF/ON switch. When it’s calling for heat or cooling the unit comes on at full capacity and runs non-stop until the temperature in the house finally reaches the chosen degree – until the thermostat is satisfied, in other words when it turns off.

The vast majority of residential systems are single speed, single stage compressors, ie: on at full speed or off. There are options available for:

• Multi-stage – more than one compressor
• Multi-speed – one compressor with more than one speed
• Variable speed – one compressor with the ability to vary its speed with load.

The complex part of these options is that you must vary the air flow in the house and the Freon flow with the compressor output. This technology is available but expensive. These systems cost more to install & maintain, but cost less to operate.

Note: As always the duct system efficiency MUST match the unit efficiency to get what you paid for. If the duct system efficiency does not match then you could be part of the National Average which is only getting a 7.4 SEER system from a 13 SEER unit.

Ok, that’s it for today but as always I want more questions from you. Don’t forget the only silly question is the one you didn’t ask!!!

~Cathy Baxley

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