The Thermiq DuoFlow controller provides comprehensive and flexible management of two pumps simultaneously based on readings from two separate sensors:

1. Central heating pump control:

   • The heating pump switches ON when the water temperature in the boiler exceeds the user-set threshold C (adjustable range 5 °C – 80 °C).

   • A constant hysteresis of 2 °C applies to the heating system (the pump switches OFF when the temperature drops below C - 2 °C).

2. Domestic hot water (DHW) pump control:

   • The hot water pump operates differentially – it switches ON only when the boiler temperature is higher than the storage tank temperature by the set hysteresis value H (setting range 5 °C – 30 °C).

   • It runs until the temperatures equalize or until the set maximum tank temperature U is reached (setting range 20 °C – 80 °C).

Main modes and additional functions:

• P Function (Hot Water Priority): When priority is enabled, the controller prioritizes heating the hot water in the storage tank first; once the set temperature is reached, it switches ON the heating pump. When priority is disabled, both pumps operate independently.

• L Function (Summer Mode): Disables the central heating pump and allows hot water heating only. In this mode, the heating pump automatically activates only as a safety measure at a critical boiler temperature (90 °C).

• Acoustic Alarm: Warns of excessive boiler temperature (90 °C) or sensor short-circuit/faults (displays error codes E1–E4).

• Protective Functions (Anti-stop & Anti-frost): Automatic activation of the pumps every 14 days for 15 seconds prevents seizure and limescale buildup, while continuous operation when the temperature drops below 5 °C protects the system against freezing.

• Manual Test & Tank Preview: A simple button press allows for a quick preview of the current storage tank temperature or manual pump activation.

EC Compliance

By affixing the CE mark, the manufacturer declares that HERZ Thermiq complies with the following relevant safety regulations:
• EU Low Voltage Directive 2014/35/EU
• EU Electromagnetic Compatibility Directive 2014/30/EU
• EU RoHS Directive 2011/65/EU
• EU WEEE Directive 2012/19/EU (Reg. No. DE 23479719)

Compliance has been verified, and the corresponding documentation and EU Declaration of Conformity are kept by the manufacturer.

• Declaration of conformity - SLO, ENG, DEU

Controller Description:

1. Power supply indicator

2. Heating pump operation indicator

3. Hot water pump operation indicator

4. Display

5. Increase setpoint temperature or value

6. Menu button

7. Decrease setpoint temperature or value

8. Controller power supply

9. Heating pump power supply

10. Hot water pump power supply

11. Hot water temperature sensor

12. Heating temperature sensor

13. Power ON/OFF switch

• Mounting Instructions

Installation Rules:

Before carrying out any work on the electrical wiring or connecting cables, ensure that the controller is disconnected from the 230 V mains voltage. Installation must be carried out by a qualified professional.

Connection Procedure:

1. Power Connection: Connect the controller's power supply cable to the 230 V AC mains supply.

2. Pump Connection: Connect the central heating pump and the domestic hot water pump to their designated outputs on the controller.

3. Sensor Installation: Securely mount the heating sensor (1.5 m) onto the boiler outlet pipe, and place the hot water sensor (3 m) into the immersion sleeve or onto the surface of the hot water storage tank, ensuring both are properly thermally insulated.

4. Parameter Setting: Adjust parameters C (heating start), U (max. tank temp.), and H (differential hysteresis) using the navigation button, and if needed, activate the priority function (P) or summer mode (L).

Wiring Diagram:

The diagram shows the wiring and operating principle of the pump controller, as well as the method for controlling the heating pump and hot water pump based on temperatures measured by the respective sensors.

• Leaflet - ENG
• Datasheet - ENG
• Image
• Mounting instructions