Operating Instructions
Table Of Contents
- Manual Organization
- Manual Conventions
- Manual Symbols
- Datamate Software
- Getting Help
- Where To Send Comments
- Introduction
- Basic Operation
- Application 2273: Multiple Compressor Heat Pump with Reversing Valve Control and Mixed Air Control
- Application 2274: Multiple Heating and Cooling Heat Pump with Mixed Air and Internal Reversing Valve Control
- Application 2290: Heat Pump ControlIer Multi Stage Slave Mode
- Overview
- Overview
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Applications
Basic Operation
The Heat Pump Controller—Multi-Stage provides Direct Digital Control (DDC) technology for
multiple compressor heat pump applications. Temperature control varies with the application.
If present, mixed air temperature control and up to three stages of electric heat or staged
heating and cooling can be provided.
Control Temperature Setpoints
The controller maintains a specified temperature setpoint based on Day/Night mode, the
heating/cooling mode, or the setpoint dial (if used).
Day/Night Mode
The controller maintains the specified day setpoint temperature during daytime hours and the
specified night setpoint at night.
Night Mode Override Switch
If the RTS has an override switch, it can be used to command the controller into day mode
for an adjustable period of time. This only affects a controller in night mode.
Control Loops
Heating Loop – maintains room temperature setpoint by turning compressors and electric
heat stages on and off.
Cooling Loop – maintains room temperature setpoint by turning compressors on and off and
using free cooling (mixed air control) when available.
Mixed Air Control Loop
The heat pump is controlled by three Proportional, Integral, and Derivative (PID) control
loops; a cooling loop and a heating loop. This section describes the mixed air control loop.
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