Working method

NIBE F1345/F1355 (EB100) is connected to accumulator tanks (CP10) and charges them.

The energy is transferred via Cetetherm AquaEfficiency (EZ2) from the accumulator tanks to the tap side. The hot water is heated when needed, but not stored.

A mixing valve is built into AquaEfficiency, which reduces the risk of scalding, as well as an HWC pump which ensures that there is always hot water at the right temperature.

For maximum efficiency and optimum utilisation of the accumulator tanks, it is important to have good stratification in the tanks. The flow through the accumulator tanks is set using the trim valves (RN1-RN5). For connection according to the Tichelmann principle, only trim valve RN1.1 is required.

The controlling hot water sensor (BT6) is positioned in such a way that 1/3 of the total accumulator volume is below the sensor. The heat pump’s start and stop temperatures are affected by the location of the sensor as well as the charge power in relation to accumulator volume.

Commissioning and adjusting

1. Check that "hot water, auto" is not selected in menu 5.1.11 - "pump speed heating medium".

2. Check that "hot water, manual" in menu 5.1.11 is set to 100%.

3. Start all the compressors that are connected to hot water.

4. Adjust the flow with the trim valve (RN1.1) so that the difference between the supply and return lines is 10 K at 55°C supply or higher (10.5 K at 45°C supply, 11 K at 35°C supply).

5. After each adjustment of the trim valve, allow the system to stabilise for 3 minutes before the next adjustment.

6. Verify the temperature difference over 10 minutes of operation.

7. When the correct temperature difference has been verified, select operating mode ”hot water, auto” in menu 5.1.11.

8. In menu 5.1.1 - "hot water settings", adjust the temperature settings for hot water charging start and stop to suitable values, depending on charge power and volume.

   TIPS If you want 55°C domestic hot water, start 53°C and stop 59°C are recommended.

9. Set “charge method” to “target temp” in menu 5.1.1.

10. Once commissioning is complete, monitor one cycle to ensure that the system does not stop at high return or condenser temperature until hot water charging is complete in BT6.