Documentation and Support (North America)

To: Cell Technicians and Service Contractors responsible for PM Service and Repair

Subject:  Changing Cooling Setpoint
Product: AIRSYS WPUs (all sizes) 

Background: Raising the Setpoint of the system provides a clear benefit in that it reduces annual electricity consumption.  You are allowing more annual free cooling time and therefore less compressor run time.  When the cooling Setpoint is changed this also impacts the heater turn on point.  This bulletin provides step by step instruction for:

A. Changing the cooling Setpoint

B. Returning the Heater turn on point to its original setting

C. Verifying both changes have been properly executed

Questions? Contact us via the 24/7 HVAC Support line: (805) 879-5432 or email: HVACSupport@tempesttelecom.com

Instructions:

A. To change Cooling Setpoint (Stp) from default of 77 to 79˚F
Press UP and DOWN together to return to main menu (indoor temperature displayed), press UP for
Press DOWN and SEL at the same time, the screen should display 0 if done correctly, otherwise return to step 1
Press SEL, the screen should display Stp
Press SEL, the screen should display the current setpoint (default is 77). 
Press UP to change 77 to 79 and the press SEL to confirm the new setting, the screen should display Stp
 
B.  Move the heater turn on point (now 52 ˚F) BACK to 50˚F
From Stp, Press DOWN until the screen display H02 and hit SEL, the screen should display 27 (or current setting)

Press UP to change 27 to 29 and hit SEL, the screen should be back at H02

Press UP to change 27 to 29 and hit SEL, the screen should be back at F36
Press UP and DOWN together to return to main menu (indoor temperature displayed)

Verifying the New Setpoints:

Indoor temperature sensor calibration can be used to set the indoor temperature to a desired reading and test the heater and compressor functions. For example, if the current temperature reading is 76°F, setting a calibration of -26°F will set the current indoor temperature to 50°F allowing you to test that the heater turns on at the desired Setpoint.

To change indoor temperature calibration:

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

Press SEL, the screen will display Stp

Press UP until n2A is displayed and press SEL, 0.0 will be displayed (current calibration)

Press UP or DOWN to change the calibration of the indoor temperature sensor

The correct behavior of the new setting should be that the lead compressor turns on at 81°F (new Setpoint +2°F) and will turn off at 75˚F. The heater turns on at 50°F (new Setpoint -29°F) and will turn off at 53°F.

Important:  Return calibration value to 0.0 before leaving the site!

Reference Document(s): Installation and Operation manual for the AIRSYS HVAC System

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