EUGENE WATER  &  ELECTRIC  BOARD

The first warm days of spring prompt some people to leap into physical activity without adequate preparation. This often leads to pulled muscles and sunburned skin.

After months of inactivity, your air conditioning system will also need preparation before enduring the strains of summer. Here are a few simple steps you can take to improve the reliability and efficiency of your cooling system this summer.

Watch the thermostat. Most people are comfortable around 74-78 degrees Fahrenheit in the summer, especially with lighter summer clothing. (See Thermostat Wars). Keeping your cooling setpoint in this range will improve efficiency and keep folks happy. People often feel chilled when moving from a warm outdoor environment into a building cooled below 70.

Severe system problems can occur if someone sets the thermostat down in the low 60s in an attempt to cool the building down faster. A thermostat is not an accelerator! Set the temperature you want and the system will get there as fast as it can. Low settings on the cooling thermostat can cause icing inside the unit and result in total loss of air conditioning and even possible equipment damage.

Cooling is not usually needed in our climate when no one is there. Manually turn units off or raise cooling setpoints when the building is unoccupied. Or invest in a programmable thermostat that qualifies for an EWEB rebate. If you already have a programmable thermostat, make sure the schedules and setpoints are correct, and you don’t have weekend operation if you don’t need it.

Remind staff to watch lighting and equipment use. If you can switch part of the lights off when there is light from windows, you will save energy directly and reduce the cooling load. Keeping lights and computers turned off when the building is unoccupied will help reduce the need for cooling when the building is unoccupied.

Change those air filters. Dust clogs the filters and reduces airflow and cooling effectiveness. Change or clean air filters at the start of the cooling and heating seasons for good system performance. Make sure the filters are the right size and are tightly installed so they do their job.

Keep condensers clear. Your air conditioner cools the building by transferring heat to the outside. Most systems have air-cooled condensers with a fan and condensing coil on the roof or in the alley. The space around these units must be kept clear so air can move freely. Also, any trash or plant debris on the condenser coil should be swept off annually (or more often if needed).

Is your outside air economizer working? An outside air economizer uses cool outside air in the mornings to cool your building instead of running the compressor. This saves energy, but the economizer must be maintained to work. You can tell if your unit has an economizer when there are automatically operated dampers in the return air and outside air. The outside air damper should be closed at night when the unit is off, and open when cooling is required and the outside air is cool.

Sometimes dampers stick, and you get too much or too little outside air. Check each economizer’s operation annually or make sure your service contractor does. If you don’t have an economizer, you may qualify for an EWEB rebate to install one (see Energy Smart Replacement Program story below).

Consider upgrades. If your air conditioning unit is more than 15 years old it is more likely to fail and can be replaced with a unit that is twice as efficient. Your HVAC contractor can use EWEB rebates to help you get a better unit when you need it.