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Master  |  SKU: DE39

TECH EU-21 CWU pump control circulation pump boiler boiler

Normal price 78,50 €
vAT included. Shipment will be charged at checkout.


Delivery and shipping

Processing time is typically 1 business day. Delivery for parcels is 1-3 business days. For freight forwarding, delivery time is 3-5 business days. Delivery times outside Germany vary.

Description

The TECH EU-21 CWU This is a compact controller for the automatic regulation of a circulation pump between the boiler and the storage tank or buffer tank. It operates based on temperature differences and reliably protects the system from unnecessary pump operation and frost.


Highlights/Advantages

Differential temperature control – Pump only runs when there is an actual need for heat
Two temperature sensors – separate recording of boiler and storage tank/buffer temperature
Integrated frost protection function – automatic activation at low temperatures
Anti-stop function – prevents the pump from blocking during extended periods of inactivity
Manual operation possible – ideal for maintenance and functional testing


Detailed description

Area of ​​application & Target audience

The TECH EU-21 CWU is designed for heating systems where heat is drawn from the boiler on one Boiler or buffer tank It is transferred. It is suitable for single-family homes as well as for smaller multi-family or commercial applications and is aimed at both specialist tradespeople and operators of conventional heating systems.

Everyday benefits

Thanks to its temperature-differential-controlled operation, the circulation pump is only switched on when sufficient heat is actually available. This prevents unnecessary cooling of the storage tank, reduces energy consumption, and extends the pump's service life.

Technology & equipment

The control system works with two temperature sensors (T1 = Boiler/Buffer Tank, T2 = Boiler). As soon as the set temperature difference is reached and the switch-on threshold is exceeded, the controller automatically activates the pump. A fixed hysteresis ensures stable and reliable operation.

Efficiency & Plant protection

In addition, the EU-21 CWU has a Antifreeze function: If the system temperature drops below 6 °C, the pump is automatically switched on to prevent frost damage. The integrated Anti-stop function The pump switches on briefly at regular intervals during prolonged periods of inactivity, thus protecting against blockages.

compatibility & System integration

The TECH EU-21 CWU is designed for operation with 230 V circulation pumps and can be easily integrated into existing heating systems. The clear display and intuitive menu allow for quick commissioning and easy parameter adjustment.


Technical data

feature Value
Manufacturer TECH Controllers
Model EU-21 CWU
Product type Pump control/Circulation pump controller
Supply voltage 230 V ±10 %/50 Hz
Power consumption 2 W
Operating temperature 5–50 °C
Max. load pump output 0.5 A
Max.Load potential-free contact 1 A
Temperature measurement accuracy ±1 °C
Temperature range sensors -30 to +99 °C
Security 1.6 A miniature fuse
Mounting hole spacing 86.5 mm

Scope of delivery

  • TECH EU-21 CWU control unit

  • 2 × temperature sensor

  • User manual

  • Assembly instructions


Accessories/Recommendation

  • Circulation pumps for heating systems

  • Buffer tank and boiler

  • Sensor sleeves and sensor mountings

  • Advanced heating controls from TECH

You can find suitable products in the relevant categories on gemashop.de.


Assembly & Safety instructions

Installation and commissioning must be carried out exclusively by a qualified specialist company. The device must be disconnected from the power supply before any work is done on the electrical installation. Sensors must be professionally mounted and insulated against external influences.


FAQ

For which systems is the EU-21 CWU suitable?
For heating systems with boiler and storage tank or buffer tank for pump control.

How does the control system work?
It switches the pump on depending on the temperature difference between the boiler and the storage tank.

Is antifreeze integrated?
Yes, the pump is automatically activated at low temperatures.

Can the pump be switched on manually?
Yes, a manual mode is available.

How many sensors are used?
Two temperature sensors – one for the boiler and one for the storage tank/buffer tank.

Is the controller pre-configured?
Yes, factory settings are available and can be adjusted.


Conclusion

The TECH EU-21 CWU This is a reliable and efficient pump control system for conventional heating systems with boilers and storage tanks. Ideal for economical, safe, and long-lasting system operation.

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