Issue:

The goal of this project is to provide a direct comparison between the AIRSYS high efficiency WPUs (Wall Packaged Units) to the other manufacturer’s WPUs that customer had commonly installed throughout their nationwide network.

Solution:

The Houston market was chosen for this trial.  Three sites were chosen that were similar in heat load and of course in the same geographical area.   One site would remain unchanged and would serve as a benchmark to calibrate the change in HVAC energy consumption attributed to the change in outside temperature as the trail began in late July and concluded in October.  The other two sites  had their WPUs upgraded from conventional to high efficiency AIRSYS WPUs after about one month of baseline energy data was collected.

  • Site A – Benchmark Site (no changes during trial)
    • One conventional 5 Ton and one conventional 3 ton both near EOL (End Of Life)
  • Site B – AIRSYS upgrade site
    • Two conventional 5 tons with only 4 months of run time (new) with no economizers
    • Replaced with two AIRSYS 3.5 Tons  in late August
  • Site C – AIRSYS upgrade site
    • One conventional 5 Ton and one conventional 3 ton both near EOL (End Of Life) with no economizers
    • Replaced with two AIRSYS 3.5 Tons  in late August

 

Results:

Site A – Benchmark Site

  • HVAC energy dropped 8% from baseline period (7-27 thru 8-26-12) to comparison period (10-15 thru 11-8-12)

Site B – Two 5 ton conventional with only 4 months run time vs two AIRSYS 3.5 ton

  • HVAC energy dropped 8% from baseline period (7-27 thru 8-26-12) to comparison period (10-15 thru 11-8-12)
  • AFTER calibrating for outside temperature decline the NET HVAC energy dropped 2 %

Site C – one 5 ton and one 3 ton conventional near EOL vs two AIRSYS 3.5 ton

  • HVAC energy dropped 5% from baseline period (7-27 thru 8-26-12) to comparison period (10-15 thru 11-8-12)
  • AFTER calibrating for outside temperature decline the NET HVAC energy dropped 2 %