Our Upgraded Cooling Systems

Last week was not much fun in our home here in Texas. The week started with an unpleasant surprise, our upstairs air conditioning stopped working and the temperature upstairs quickly rose to about 90F (32C). Our air conditioning units are both covered by our home warranty so I quickly placed a service call and they told us that a local AC service company would be contacting us. Both of our upstairs and downstairs cooling condensers (outdoor fan units) are original to the house, so they are about 20 years old.

Our Old AC Condensers were installed in 1989!

Several days passed and it wasn’t until late Wednesday that someone showed up to try and fix the upstairs cooling system. To cut a long story short, they couldn’t fix it and had to order some replacement parts. In the meantime, our downstairs cooling system stopped working and the temperature in our house was quickly becoming unbearable. The thermostat upstairs read 99F (37C) but I suspect it was hotter than that, I think the digital gauge stops at 99F. Outside had been about 105F all week and that’s what it felt like in our home. Texas homes in the middle of July absolutely need air conditioning!

With no air conditioning working at all I had to do something and waiting for our home warranty company was not an option, I made numerous phone calls to them and they did not seem to grasp how serious our situation was. Our poor dogs were panting all day long and luckily our tile floors and various fans provided some relief.

The smaller upstairs unit removed

I remembered an old colleague from work who did air conditioner work and after a couple of emails he had two brand new ac units on order. The replacement units were Nordyne units with a SEER rating of 13, much higher than the old units which we estimated were a 9 or 10 SEER rating. Our work began on a hot Friday afternoon and we had the old units removed within an hour. I had done some preparation work by cutting back our overgrown trumpet vines a little. The smaller 2 tonne condenser was fairly light and easy to move but the larger 4.5 tonne condenser took some “convincing” to get it cleared.


We loaded up the old condenser units on a trailer to take off to a recycling center and started on the work of installing the new Nordyne units. The first thing I noticed was that the new units were much more compact, the compressors were actually in the middle of the units whereas the old unit’s condensers took up a whole side. Placing the compressor in the middle means that the cooling coils can span almost all of the four sides of the units.

One of the new condenser units

So how much more efficient will the new units be? SEER stands for Seasonal Energy Efficiency Ratio and a quick Wikipedia search showed that substantial energy savings can be obtained from more efficient systems. It has been shown that when upgrading from SEER 9 to SEER 13, the power consumption is reduced by 30% (equal to 1 – 9/13). It is claimed that this can result in an energy savings valued at up to $300 per year depending on the usage rate and the cost of electricity. I wanted to see if this was actually true so I took a look at the figures (Taking some basic measurements of how long the new units run per day I figured the old units ran for about 8 hrs a day for the 150 hot Texas summer days and the new units are running just 6 hrs a day;)

I will be tracking our monthly electricity bill with the new air conditioning units and will post an update on our actual savings at the end of the year.

The new installed AC units finished

My final task was to clean up the area and fit a gate to prevent our dogs getting into the area. The old units were much bigger and deterred our dogs from walking around them. The new more compact units mean there is plenty of space for our little hounds to cause trouble. I remembered that we had an old gate left over from our last yard project so I fitted a piece of barn wood to bridge the gap and “hey presto” our new AC units have their own gated enclosure.

Please leave us your thoughts;

• Do you have new super efficient cooling systems rated SEER 13 or greater?
• Are you thinking about upgrading your old AC units to save energy?

systems. For example by upgrading from SEER 9 to SEER 13, the power

consumption is reduced by 30% (equal to 1 – 9/13). It is claimed that

this can result in an energy savings valued at up to US$300 per year

depending on the usage rate and the cost of electricity.