Water Volume And Expansion Vessel Pressure - LG THERMA V HN0613T Installation Manual

Water Volume and Expansion Vessel Pressure

Inside expansion vessel is included which is 8 liter capacity with 1 bar pre-pressure. That means,
according to the volume-pressure graph, total water volume of 230 liter is supported as default. If
total water volume is changed because of installation condition, the pre-pressure should be
adjusted to secure proper operation.
The system contains a backup heater
The system does NOT contain a backup heater
* The internal water volume of the outdoor unit is NOT included
- Pre-pressure is adjusted by the total water volume. If the indoor is located at the highest
position of the water circuit, adjustment is not required.
- To adjust pre-pressure, use nitrogen gas by certificated installer.
2.4
2.1
1.7
1.4
1.0
0.7
0.3
20 60
Adjusting pre-pressure of expansion vessel is as following :
Step 1. Refer "Volume-Height" table.
If installation scene is belong to Case A, go to Step 2.
Otherwise, if it is Case B, do nothing. (pre-pressure adjustment is not required.)
Otherwise, if it is Case C, go to Step 3.
Step 2. Adjust pre-pressure by following equation.
Pre-pressure [bar] = (0.1 x H + 0.3) [bar]
where H : difference between unit and the highest water pipe
0.3 : minimum water pressure to secure product operation
Step 3. Volume of expansion vessel is less than installation scene.
Please install additional expansion vessel at the external water circuit.
Volume-Height Table
V < 230 liter
H < 7 m Case B
H ≥ 7 m
Case A
If
100 140 180 220
Maximum total water volume (liter)
V ≥ 230 liter
H : Difference between unit and the highest
Case A
water pipe
Case C V : total water volume of installation scene
PIPING AND WIRING FOR INDOOR UNIT
Minimum water volume
260 300 340
73
20 L
80 L