12-3
CONTROL SYSTEM
SM OU12HP 2-E.2 GB
12.2.5 RV
Reverse Valve set the direction of refrigerant flow in the system, thus setting the operation
mode for cooling or heating.
When the solenoid is powered, system will work in heat mode.
12.2.6 EEV
Expansion valve operated by step motor which controls the size of the orifice.
12.2.7 HMI
Consists of Four “7-Segments” + four Push buttons for display, monitoring and setup
features.
12.2.8 Dry Contacts
Dry contacts are used to interface the system with an external building management system
(BMS).
12.2.8.1 ODU Dry Contacts
• Night input. Switches the system to night mode when closed. During night mode, the
outdoor unit speed will be reduced in order to reduce the system noise level.
• SB input. System will be turned to Stand-by when the contact is closed.
• Power Shedding input. Limits the maximum power consumption when closed.
• Alarm output indicates a failure in the system.
Alarm output will be activated when there in the following ODU Faults/Protections
1 to 11, 13 to 20, 22 to 26, 28 to 29.
Alarm output will be OFF when the Fault/Protection is cleared.
12.2.8.2 IDU Dry Contacts
Presence detecter input.
12.2.9 Temperature Sensors
CTT – Compressor Top Temperature
OAT – Outdoor Air Temperature
OCT – Outdoor Coil (heat exchanger inlet) Temperature
OMT – Outdoor Coil (heat exchanger) Temperature
HST – Heat Sink Temperature
ICT – Indoor Coil (heat exchanger) Temperature
RAT – Return Air Temperature (Indoor Unit)
To Next Page
Loading...
