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Establish a preventative maintenance
program for your heating, venting and air conditioning (HVAC) equipment and
systems. Maintenance activities can save up to 30% of fan
energy and up to 10% of space conditioning energy use.
Ensure that you regularly:
Install a high efficiency packaged
heating, ventilation and air conditioning (HVAC) system. These
can use up to 40% less energy than systems that just meet minimum standards.
Look for a high SEER (Seasonal Energy Efficiency Ratio) or, on larger units,
EER (Energy Efficiency Ratio). You can purchase units with SEER above 12 or EER
above 11. Specify high-efficiency air conditioning equipment when your system
needs to be replaced, and save 25% to 35% on your investment annually.
- Change or clean all air filters, preferably every
- Clean all heat exchanger surfaces, water and
refrigerant coils, condensers and evaporators.
- Repair leaks in piping, air ducts, coils, fittings and
at the unit(s).
- Replace defective equipment insulation, ducting and
When old motors fail, replace them with
premium efficiency motors that operate at a lower annual cost.
Ensure you specify the proper sized motor for the application. View cost
reduction strategies for motors.
Install variable speed drives (VSDs) on
large motor loads, where appropriate, to further reduce energy
Use outside air and water
side-economizers for "free cooling" when outside air
temperatures and conditions permit - during the spring and fall.
In facilities with older chillers,
consider replacing them with new, energy-efficient units that
operate at or below .60 kilowatts per ton. View a chilled water system analysis
tool to improve efficiency.
Reduce air conditioning and heating
hours by installing a timer to turn off the system when the
building is unoccupied.
Install an energy efficient attic fan
or evaporative cooler. Attic fans or evaporative coolers help
reduce or replace air conditioner use.
Add controls to exhaust fans. Exhaust
fans remove air that has already been conditioned. Install
timers and switches to shut them off when they are not needed or when the
building is unoccupied.
Install an ENERGY STAR programmable
thermostat to automate your HVAC system. An
"old-fashioned" thermostat turns the HVAC on and off based on
temperature, not whether the building is occupied, or whether you benefit from
the cooling/heating. A programmable thermostat can optimize HVAC operation
"24/7" based on your needs. For example, instead of heating or
cooling all night, so you can enter a comfortable building in the morning, this
"smart thermostat" can turn on the HVAC one hour before you arrive,
based on your daily/hourly needs. The cost can be $25 to $150, and it could cut
your HVAC costs about 30%. Add a locking cover to prevent tampering with
Manage your thermostat.
In winter, set office thermostat offices between 65 and 68 during the
day/business hours, and 60 to 65 degrees during unoccupied times. In summer,
set thermostats between 78 and 80 degrees during the day/business hours, and
above 80 degrees during unoccupied hours.
Adjust thermostats higher when cooling
and lower when heating an occupied building or unoccupied areas within a
building, e.g., during weekends and non-working hours.
Consider installing locking devices on
thermostats to maintain desired temperature settings.
Install programmable thermostats that
automatically adjust temperature settings based on the time of day and day of
the week. If you have multiple HVAC units, set your thermostats
to return to the occupied temperature a half an hour apart.
In larger facilities with energy
management systems (EMS), verify that temperature set points and operating
schedules are correct for the controlled equipment. For EMS systems
that no longer operate as initially designed, consider a retro-commissioning
project to restore the system's functionality.