HVAC Control System

Fully flexible HVAC Controls to cover any size installation
8 Control Loops in one panel

Fully flexible HVAC controls to cover any size installation

We have designed and delivered a variety of HVAC controls based on a standard modular control panel. These are available in both 2 and 4 control loop units, with the possibility of customisation to include many more channels. Being a fully flexible system, it is easily integrated with the customers’ existing sensors and control valves, but new equipment can be supplied and installed also.

Each control channel can be connected to a heating control valve, or a cooling control valve. Split range functionality is possible where both heating and cooling valves can be operated together based on the control requirements.

The standard build can accept thermistor temperature sensors which are the industry standard for HVAC systems. This can be customised to integrate with any existing temperature sensors such as PT100 or thermocouples.

The system is pre-programmed and can be fully configured through the supplied colour touchscreen requiring little experience with PLC programming. All settings can be viewed through the display with a user password being required to make any changes.

The units are normally supplied with a touchscreen fitted in the front panel. It is possible to remotely mount the screen via an Ethernet connection, or share a single screen between multiple controllers.

The on-screen text can be configured during initial commissioning to allow the users system names and tags to be integrated into the software.


The touchscreen provides a data logging facility which records historic data which can then be downloaded or displayed through the unit itself. It records the measured temperature, the set point and control output values.

All systems include software to allow summer and winter compensation. This monitors the outside air temperature, and adjusts the control set point to suit the changing conditions. The amount of adjustment and at what levels it occurs is fully configurable through the display. A temperature probe would usually be located in the outside air intake duct to enable this feature.

All components in the system are commercial off the shelf with the appropriate manufactures support. Control is achieved using a standard PLC which allows almost unlimited customisation and integration with existing systems.

All systems include the facility to monitor the compartment temperature as well as the air from the air handling unit. This allows cascade control of firstly the air handling units outlet temperature, and also of the compartment temperature. A temperature probe would usually be located in the compartment extract air duct to enable this feature.

As standard the system includes the facility to connect to an external set point potentiometer. This can be remotely mounted to allow the user to quickly and easily adjust the control point from a convenient location. This can be calibrated to an existing remote set point facility or a new potentiometer can be installed.



Power Supply: 110-24V AC
Valve Drive Supply: 24V AC/DC
Valve Analogue Output: 4-20mA / 0-10V DC
Digital Output: Alarm VFC
Remote Set Point Input: 0-10V DC


Size (WxHxD):
2 Control Loop – 300x300x210
4 Control Loop – 400x500x210
Protection: IP66
Temperature Rating: -20°C – 65°C


Colour Touchscreen: Yes
Controller: AB Micro 820
Volt Free Alarm Output: Yes
Analogue Control Outputs: 2/4
Heat Control: Yes
Cooling Control: Yes
Remote Set Point Facility: Yes
Control Strategy: PID
Summer/Winter Compensation: Yes
Room Temperature Cascade Control: Yes
Temperature Sensor Inputs: Thermistor
PLC Memory Battery: Not needed

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