To: Service Contractors responsible for PM Service and Repair

Subject: Turning off Free Cooling (FC) functionality of AIRSYS WPUs
Background: In severe conditions, it may be necessary to disable Free Cooling (FC) functionality (closing fresh air damper) of the AIRSYS WPUs.  This should only be done in extreme conditions.  All AIRSYS equipment is optimized for reliability and energy efficiency and disabling FC will result in significant loss in energy efficiency.  In some sites, this could mean an increase of more than $2000 per year in energy cost. 

 

Shutting off FC is not recommended for sites receiving only a dirty air filter alarm (A15 and/or A16).  Though dirty filters do reduce the efficiency of the WPUs, there is still significant energy savings from the FC mode.  The recommended course of action is to replace the dirty air filter which will allow the WPUs to operate normally.  If it is not possible to replace the dirty air filter in a reasonable amount of time, there are two options for disabling FC.

 

Option 1 (recommended): Shut off FC when dirty air filter alarm (A15 and/or A16) is triggered

Option 2: Completely turn off FC

 

 


 

Instructions:

Option 1 (Recommended): Turn off Free Cooling (FC) when filter alarm is triggered (small impact on efficiency, recommended for sites where filters are clogged in 2-3 month)


1. Press UP and DOWN together to display indoor temperature (main menu) 

2. Press UP until SET is displayed on screen

3. Press DOWN and SEL at the same time, the screen should display 0

4. Change to 6 and press SEL, the screen should display L01

5. Press UP  until you get to  L05 and press SEL, the screen should display F01

6. Press DOWN until you get to F24 and press SEL, the screen should display no

7. Press UP to change to Yes, and press SEL, the screen should return to F24

8. Press UP and Down together to return to indoor temperature (main menu)


Option 2: Completely Turn off Free Cooling (FC)


1. Press UP and DOWN together to display indoor temperature (main menu),

2. Press UP until  is displayed on screen

3. Press DOWN and SEL at the same time, the screen should display 0

4. Change to 6 and press SEL, the screen should display L01

5. Press UP  until you get to  L05 and press SEL, the screen should display F01

6. Press DOWN until you get to F03 and press SEL, the screen should display Yes

7. Press UP to change to no and press SEL, the screen should return to F03

8. Press UP and Down together to return to indoor temperature (main menu)

 

Note: Compressors will still operate normally when temperature is elevated for both options.