Heat pump - Johnson Controls - LIT-12011950 - Building automation software - Smart Equipment Controller - 5.0

Smart Equipment Controls Sequence of Operation Technical Bulletin

Brand
Johnson Controls
Product name
Smart Equipment Controller
Document type
Technical Bulletin
Document number
LIT-12011950
Version
5.0
Revision date
2024-06-06
Product status
Active
Language
English

This section describes cooling and heating setpoints and related data, inputs, outputs, and operation with a heat pump unit configuration.

This section does not try to determine how a heating or cooling call is made. Only features unique to heat pump setpoints and related data, inputs, outputs, and operation are described.

Setpoints and related data

The setpoints and related data include the following items:

  • Number of cooling stages installed (#ClgStgs)
  • Number of heating stages installed (#HtgStgs), any and all compressors are considered one stage
  • Number of heat pump stages (#HtPumpStgs), this is the same as the number of cooling stages installed
  • Number of refrigeration systems (#RefrigSys), this is the number of physical coolant circuits
  • Defrost curve selection (DefrostCurveSel)
  • The Outdoor Air Temperature Permission setpoint is exposed in the Details - Heat Pump menu. This temperature represents the outdoor air temperature above which defrost cycles are not permitted. If users are experiencing issues where a defrost cycle is required, but not occurring due to the outdoor air temperature, adjusting this setpoint may help.
  • Compressor Delay Enable (CompDelayEnable), this parameter adds a 30 second delay to the compressors when entering and exiting defrost. It also adds a delay to the reversing valve that expires 5 seconds before the compressor delay.

Inputs

The inputs include the following items:

  • Operational space temperature (OprST)
  • Applicable thermostat inputs (Tstat-Only control)
    • Y1
    • Y2
    • W1
    • W2
  • Condenser Coil Temp 1 (CC1)
  • Condenser Coil Temp 2 (CC2)
  • Operational Outdoor Air Temperature (OprOAT)
  • Heat Limit1 Switch (Limit)

Outputs

The outputs include the following items:

  • C1
  • C2
  • FAN
  • CN-FAN
  • H1 [as Rev Valve]
  • H2 [Aux Heat]