Midea R32 & R290 Wiring and Commissioning Guide
Introduction
This document provides detailed information on the wiring and commissioning procedures for Midea R32 and R290 heat pump systems. It covers the identification of components, electrical connections, and various operational settings for optimal performance.
Wiring Components and Connections
The following components are essential for the proper functioning of the Midea R32 & R290 systems:
- 3/2 Port Valve (SV-1): Controls the flow of refrigerant.
- External Pump: Assists in water circulation.
- Third Party Room Thermostat (Heat Call): Allows external control of heating.
- Controller: Manages the overall operation of the system.
- DHW Sensor: Monitors the temperature of domestic hot water.
- TBT Sensor (if required): Monitors temperature in specific applications.
Detailed wiring diagrams are provided for single-phase and three-phase power supplies, illustrating the connections for various components.
Hydroboard PCB Layout
The Hydroboard PCB is the central control unit. Key connection points and components include:
- Power Supply Port: For 220V AC input.
- Sensor Information Input: Connects to various sensors.
- External Function: For additional functionalities.
- Microchip for Refrigerant System: Manages refrigerant operations.
- Microchip for Hydronic System: Manages water-related operations.
- Hydronic Module Terminals: Connects to the hydronic module.
- Signal Output and Input: For communication and control signals.
- Communication with ODU/HMI: Connects to the outdoor unit and human-machine interface.
- Sensor Cable Ports: Connects sensor cables.
- Control Signal Terminal Blocks: For control signals.
- Signal Cable Terminals: For signal cables.
Electric Wiring Details
The document outlines the electric wiring for both R32 and R290 models, including specifications for maximum overcurrent protector (MOP) and recommended wiring sizes (mm²) for different unit capacities and power supplies (1-phase and 3-phase). Tables provide specific values for various kW ratings.
3rd Party Capabilities and Connections
The system supports integration with third-party devices. Key connections include:
- Solar Energy: For solar thermal integration.
- Room Thermostat Input (high voltage): For connecting high-voltage thermostats.
- SV1 (3-way valve): Connection for the 3-way valve.
- Pump (zone2 pump), Outside circulation pump (/zone1 pump), Solar energy pump, DHW pipe pump: Connections for various pumps.
- Tank booster heater, External backup heater: Connections for heating elements.
- SV3 (3-way valve): Another 3-way valve connection.
Specific terminal connections for the controller and outdoor unit are detailed.
3/2 Port Valve Operation
The document explains the operation of the 3-port valve, differentiating between spring-returned valves and those powered on/off. It specifies the wire connections for DHW and heating functions.
Pump (O) Wiring
Wiring diagrams for the external pump (Pump O) are provided for both R32 and R290 models. Specifications include voltage, maximum running current, wiring size, and control port signal type.
TBH (Tank Booster Heater) Wiring
Information regarding the Tank Booster Heater (TBH) is presented. It is noted that for load currents greater than 0.2A, an AC contactor must be used. Wiring diagrams for electric heaters for water tanks and internal electric heaters are included.
Sensors
The document identifies various temperature sensors and their corresponding connection points on the PCB:
- Tbt1: Water temp sensor of balance tank (connects to CN24).
- Tw2: Water temp sensor of zone 2 (floor heating loop) (connects to CN15).
- T5: Water temp sensor of domestic water tank (connects to CN13).
- Tsolar: Water temp sensor of Solar water temp (connects to CN18).
Third Party Room Control Wiring
Instructions are provided for integrating third-party room thermostats with the Midea R32 and R290 systems. For R290, it is specified that if a room stat with a 230v output is used, a relay is required. Wiring configurations for different methods of room thermostat connection are shown.
Contactors/Relays
Images and basic wiring diagrams of contactors and relays are shown, illustrating their function in the system. A relay circuit diagram shows a push button, relay coil, and connections to a 220V lamp and AC mains voltage.
Controller Wiring
Detailed wiring diagrams for the controller are provided for both R32 (5 Core) and R290 (2 Core) systems. This includes connections for the wired controller, hydraulic module, and Modbus communication. Specifications for input voltage, wire size, wire type, and wire length are listed.
Commissioning Procedures
The commissioning section outlines the steps involved in setting up the system:
- Serviceman & password access.
- DHW (Domestic Hot Water) set-up.
- Cooling mode configuration.
- Heating set-up.
- Room thermostat configuration.
- Test run procedures.
- Climate curves adjustment.
- Operation parameters setting.
The document details the serviceman menu content for both R32 and R290 models, listing various settings such as DHW mode, cooling/heating modes, auto mode, temperature settings, room thermostat, holiday settings, and factory reset options.
Domestic Hot Water (DHW) Settings
Specific settings for domestic hot water are detailed, including DHW mode, disinfection, priority settings, pump control, and temperature limits (dT5_ON, dT1S5, T4DHWMAX, T4DHWMIN). Both R32 and R290 interfaces for these settings are shown.
Heating & Cooling Settings
The guide provides comprehensive settings for heating and cooling modes for both R32 and R290 systems. This includes:
- Cool mode settings (Cool mode, t_T4_FRESH_C, T4CMAX, T4CMIN, dT1SC).
- Heat mode settings (Heat mode, t_T4_FRESH_H, T4HMAX, T4HMIN, dT1SH).
- Specific settings for radiators/underfloor heating are also detailed.
Ambient working temperature settings are also provided.
Serviceman Test Run
The document details the procedures for performing a serviceman test run. This includes activating settings, point checks, air purge, circulation pump running, and mode-specific running tests (cool and heat modes). The R290 interface for test run, point check, and air purge is illustrated.
Heat Pump Installation - Minimum Water Volume and Flow Rate
Important installation requirements are highlighted:
- Minimum Water Volume: The total water volume in the installation must be at least 40 liters, excluding the internal water volume of the outdoor unit.
- Minimum Flow Rate: The minimum flow rate must be guaranteed in all conditions, especially during defrost or backup heating. Tables specify the minimum flow rate required for 4-10 kW and 12-16 kW units.
