CVAHU HC Stages

Description

The minimum on/off times, Cycles/ hour, Minimum and maximum recovery ramps are set for heating and cooling stages of a CVAHU application.

Purpose

Define heating and cooling (h/c) stage parameters, including minimum on and off times.

Mode

Off-line or On-line.

Procedure

  1. Click the H/C Stages button on the left pane to open the Heat-cool Stages Configuration page.
  2. Select MinHeatOn/Off for Heating and MinCoolOn/Off for Cooling.
  3. Enter information into available fields.
  4. Click Commit to save the settings or Reset to revert to the last saved settings.
  5. Click Next to display the Zone Options Configuration page or Back to display the Economizer Parameters Configuration page.

Fields           

Name Definition
Min. On/Off MinHeatOn enables minimum on/off time. MinHeatOff replaces set minimum on/off times with a 30-second default.

MinCoolOn enables minimum on/off time. MinCoolOff replaces set minimum on/off times with a 30-second default.
Cycles/Hour Cycles per hour (cph). Enter a value from 2 through 12. For example, cph for conventional heating stage one is normally 3 cph. Consult your hardware installation guide for recommended values.
OAT Lockout Outside Air (OA) temperature lockout. OA temperature values below the Cooling lockout setting disables the cooling stages. OA temperature values above the heating lockout setting disable the heating stages.
Min. Recov. Ramp Minimum recovery ramp (degrees per hour). Enter a value from 2 through 20 for cooling; 3 through 20 for heating. See Excel 10 System Engineering manual, form number 74-2958, for a discussion of the recovery ramp feature of the CVAHU.
Min. Recov. Ramp Oa Temp Minimum recovery Oa (outside air) temperature. Enter value from 0 through 100 for cooling or heating. See Excel 10 System Engineering manual for a discussion of the CVAHUs recovery ramp feature.
Max. Recov. Ramp Maximum recovery ramp (degrees per hour). Enter a value from 6 through 20 for cooling; 8 through 20 for heating. See Excel 10 System Engineering manual for a discussion of the recovery ramp feature of the CVAHU.
Max. Recov. Ramp Oa Temp Maximum recovery Oa (outside air) temperature. Enter value from 0 through 100 for cooling or heating. See Excel 10 System Engineering manual for a discussion of the recovery ramp feature of the CVAHU.
Fan Run On Time Enter an amount of time (from 0 to 120 seconds) the fan will continue to run after the last stage of heating or cooling has switched off. This value is only applicable during Unoccupied times, and during Occupied times if the Fan Control field is set to AutoFan.

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