Filling Of The Primary Heating System - Danfoss Termix VVX-I-R FI - 7 Series Operating Manual

Termix VVX-I-R FI - 7 Series DS fully insulated

Filling of the primary heating system

A flushing bypass or similar should be mounted.
Only introduce heating network water in the HIU once it has been flushed.
1. First fill
When carrying out the first fill, the heat exchanger must be slowly filled
with water until it reaches working pressure.
2. Pressure gauge
The HE pressure gauge indicates the pressure of the HE system. This
instruction must be followed strictly to avoid dangerous situations.
3. Supply hose
An isolation valve with plug is installed in the HE return line. To fill the
system, the isolation valve must first be closed, the plug removed and
a supply hose connected. On re-opening the isolation valve, system fill
can commence.
4. Pre-pressure
The expansion vessel is supplied prepressurised to 0.5 bar.
The pre-pressure required for the individual heat interface
unit will depend on system head (the distance between
the lowest and highest point in the system), for example:
Height (m)
0-5
5-10
10-15
15-20
5. Filling stop
When filling the system with water, the pressure gauge should be
observed closely. Filling must stop when the pressure gauge shows a
pressure approximately 1-2 bar higher than the pre-pressure setting. The
isolation valve is then closed, the hose removed and the plug replaced.
18 | © Danfoss | 2021.06
Presssure (bar)
0,5
1,0
1,5
2,0
26
see diagram
Re-tighten connections
After water has been added to the system and the system has been
put into operation, re-tighten ALL constructions.
LGB40450