Nibe S1255-12, Installer Manual, Page: 28 / 92

Preparations
1. Check for water in the hot water heater and climate
system.
Caution
Check the miniature circuit-breaker and the
motor protection breakers. They may have
tripped during transportation.
NOTE
Do not start S1255 if there is a risk that the
water in the system has frozen.
Filling and venting
Caution
Insufficient venting can damage internal com-
ponents in S1255.
FILLING AND VENTING THE CLIMATE
SYSTEM
Filling
1.
Open the filling valve (external, not included in the
product). Fill the coil in the hot water heater and the
rest of the climate system with water.
2. Open the vent valve (QM22).
3.
When the water that exits the vent valve (QM22) is
not mixed with air, close the valve. After a while the
pressure starts to rise.
4. Close the filling valve when the correct pressure is
obtained.
Venting
1.
Bleed the heat pump via a vent valve (QM22) and
the rest of the climate system via their relevant vent
valves.
2. Keep topping up and venting until all air has been
removed and the pressure is correct.
NOTE
The pipe from the coil in the container must
be drained of water before air can be released.
This means that the system is not necessarily
bled despite the flow of water when the vent
valve (QM22) is opened.
FILLING THE HOT WATER HEATER
1. Open a hot water tap in the house.
2. Fill the hot water heater through the cold water
connection (XL3).
3. When the water that comes out of the hot water
tap is no longer mixed with air, the water heater is
full and the tap can be closed.
FILLING AND VENTING THE BRINE SYSTEM
When filling the brine system, mix the water with anti-
freeze in an open container. The mixture should be
protected against freezing down to about -15°C. The
brine is topped up by connecting a filling pump.
1.
Check the brine system for leakage.
2. Connect the filling pump and return line on the brine
system's filling connection (accessory).
3.
If alternative 1 is used (level vessel), close the valve
under the level vessel.
4.
Close the reversing valve in the filling connection.
5.
Open the valves on the filler connector.
6. Start the filling pump.
7. Fill until liquid enters the return pipe.
8. Close the valves on the filler connector.
9. Open the reversing valve in the filling connection.
10. If alternative 1 (level vessel) is used, open the valve
under the level vessel (CM2).
NIBE S1255 Chapter 6 | Commissioning and adjusting 28
6 Commissioning and adjusting