Monday, 25 March 2013
Getting Service Today
clear

Just call us at anytime night or day at 615-832-8500 or e-mail us your information by clicking on the vipemail@interstateac.com link on any web page. You can also click the "Schedule Service Call" button that appears most pages.

After normal business hours our on-call personnel will take good care of you. Normal business hours are 7:00 am till 5:00 pm Monday thru Friday. You can learn more about how we dispatch calls for service both here and here

signature

 

clear
Posted on 03/25/2013 1:54 AM by Eddie Hutton
clear
Sunday, 24 March 2013
How Cars Were Air Conditioned 60 Years Ago
clear
car cooler on 1950 studebaker Old car ad Old photo of car cooler unmounted

We don’t service automotive air conditioners, but recently  I came across a couple of items I thought were interesting.  A  1950 Studebaker photo with an evaporative cooling unit in the side window along with the flyer promoting the same product.  The flyer boasts, “Now Continuous Cool Fresh Air inside your car in the hottest weather”.  You can see the airline car cooler mounted on the road side front window of the Studebaker.  The way it worked was when the car was moving forward, air flowing through the unit turned a drum with a cloth wrapped around it in and out of a water pan. This evaporated the water cooling the air a few degrees.  There were a few problems; it only worked in desert like climates, you had to add water  (one gallon would cool for about 100 miles), it only cooled air a  few degrees, and it didn’t cool at all if the car was stopped.   It had one advantage in that it increased the humidity in the car making occupants more comfortable.

old airlineThe brochure ends with “SINCE THE WAR UNTOLD MILLIONS HAVE BEEN ASKING FOR CAR COOLERS. Our greatly enlarged factory is now hopeful of being able to fill the bulk of these orders . . . “  A friend of mine recounts when he was 10 years old he rode with the family in that Studebaker across the Utah desert in July with this contraption beautifying the car and hanging out the window.  Finally his father gave up and decided to do the remainder of the trip to Los Angeles at night when the desert is a lot cooler.  

Nashville would never have become the thriving place it is today without air conditioning in our homes, our cars, and our workplaces.  The evaporative cooler would not have done it in Nashville.

Click photos to enlarge.

clear
Posted on 03/24/2013 1:00 AM by Eddie Hutton
clear
Friday, 15 March 2013
Cooling Season Maintenance Checklist
clear

Spring is almost here and the weather in Nashville is warming up.  Don’t wait for hot weather before your having your air conditioning system checked.  Do you remember the blog post last October about Why Air Conditioners  Fail on Hot Days.  Maybe you read  What Makes Air Conditioning Systems Fail. The reasons are pretty simple; dirty filters reducing air flow, faulty contactors, and the starting capacitor.  These are the main reasons. Of course there are a lot more things that can go wrong, motor failures, loss of refrigerant, thermostat failures, loose wires, etc.   A maintenance check  on your cooling system before the hot weather is very important to do every year.  The simple things such as changing filters you can do yourself but checking refrigerant takes some expensive tools and training.. Here is a list of items our technicians will check during the spring maintenance call.

  • Filters
  • Contactors
  • Starting capacitors
  • Thermostat operation
  • Compressor motor current draw
  • Operating refrigerant pressures
  • Blower bearings
  • Inside blower motor current draw vs. specifications
  • Outside blower motor current draw vs. specifications
  • Compressor motor current draw vs. specifications
  • Basement condensate pump
  • Attic  condensate pan and drain
  • Attic condensate float switch
  • Inside coils – clean if necessary
  • Attic coils-– clean if necessary
  • Outside coils– clean if necessary
  • Check outside coils for hail damaged fins
  • Safety switches
  • Wiring connections

Needless to say it takes time to check all these items so make the summer maintenance call well before summer.

signature

clear
Posted on 03/15/2013 1:00 AM by Eddie Hutton
clear
Friday, 1 March 2013
What about Geothermal HVAC in Commercial Applications
clear

Roger Eldridge, Partner , and Jeff Stone, Technician, explain how geothermal systems  heat and cool commercial buildings.

Commercial applications tend to be schools, universities, and churches.  We have done projects as small as a bank and as large as a school. We are doing a project at Lipscomb University for the nursing building that is geothermal. They are taking a building that was recently a water source heat pump system and they are converting it to geothermal. The front end costs are high but overtime it will pay for itself and once it’s paid for the efficiencies will more than pay for itself in the future. We all know that energy costs are not going down they are going up. 

What kind of payback period is there?  It depends. It could be as short as five years or as much as twenty years.  Obviously the larger the facility, and there are a lot of factors that play into that, runtime, weather, large increases in utility costs. We can only calculate payback based on what we know today. 

One Nashville geothermal commercial installation needs capacity of 42 tons.  One ton equals 12,000 BTUs per hour of heating or cooling (more). A 500 ft deep well has 1,000 feet of continuous pipe and provides for 3.5 tons.  This installation has 12 wells spaced 25 feet apart.  Thus 12 times 3.5 equals 42 tons.

Jeff Stone, who was in charge of installation, explained the equipment room. There are 9 heat pump units of various capacities from 2 tons to 12 tons. The total capacity of all 9 units is 42 tons.  Each unit is ducted to a different zone in the building. By having separate units  one zone can be heating with another cooling.  Two large diameter paralleled pipes coming from the wells surround two sides of the room. One pipe is the supply line and the other the return line. A single electronically controlled variable speed pump adjusts the flow of water throughout the system.  Valves are provided to protect the water from draining out in the over 12,000 feet of piping in case the motor needs to be repaired.  An air separator lets any air in the pipe loop to bleed off without losing any water thus preventing an air lock.  The main supply and return pipes are tapped at each unit to supply water to the unit. Valves allow the water supply for the unit to be shut off permitting maintenance on that unit such as replacing a coil without shutting down the entire system. Each unit has one or two easily replaced air filters.

clear
Posted on 03/01/2013 1:30 AM by Roger Eldridge
clear