[HydCrtH21] Hydraulic circuit for heating, flow temperature control

Controls the flow temperature.

A parameter in the program defines if the plant stops when the flow temperature sensor has a fault.

This program block has the following optional functions:

Option: Hot water demand

Generates a hot water demand and displays it on BACnet with a calculated value object.

Option: Frost protection

Checks if the flow or the return temperature are in alarm due to a low limit violation and generates an alarm with a binary calculated value. It deactivates all limits for the heating controller and activates the hot water demand.

Option: Maximum controller output limitation

An interface reads the signal for charge priority limitation from a domestic hot water plant (over BACnet).

Option: Maximum return temperature limitation

A PID controller limits the return temperature to a maximum, depending on the outside air temperature. You can adjust the setpoint for the maximum limitation in a CHAR_LIN in the program.

Option: Minimum return temperature limitation

A PID controller limits the return temperature to a minimum.

Option: Overtemperature detector (1xBI)

Reads the signal from an overtemperature detector and generates an alarm. The program logic stops the temperature control and closes the valve. If the option "Pump delay after overtemperature" is active, the pump stops with a delay. Otherwise, the pump stops immediately.

Option: Pump activation at low outside temperature

The pump always runs below a certain limit for the outside temperature. This is to increase the frost protection.

Option: Pump delay off after overtemperature

Defines a delay off for the pump after overtemperature (signal from the overtemperature detector or from the safety temperature limiter or from the high limit alarm from the flow or return temperature). The reason for this is that in well-insulated pipes, the pump must run for some time to cool down the water. Otherwise, the plant recovers from the overtemperature condition very slowly.

Remove this option for floor heating or cooling.

Option: Return temperature (1xAI)

Creates an analog input for the return temperature and reads its signal. It can generate an alarm (high and low limit).

Option: Safety temperature limiter (1xBI)

Reads the signal from a safety temperature limiter and generates an alarm. The program logic stops the temperature control and closes the valve. If the option "Pump delay after overtemperature" is active, the pump stops with a delay. Otherwise, the pump stops immediately.

Option: Switch-off delay for pump

Defines a switch-off delay for the pump. It is preset to be short and is parameterizable in the program.

See also

• Predefined I/Os
• Trend types
• Module families

See also

• Predefined I/Os
• Trend types
• Module families