144
14. Servicing
Mode
14.1 How to Take Out Front Plate
Please follow the steps below for take out front plate. Before removing the front plate of indoor unit, always switch off
all power supply (i.e. indoor unit power supply, heater power supply and Tank Unit power supply).
1 Remove the 2 mounting screws which located at bottom of the front plate.
2 Gently pull the lower section of the front plate towards you to remove the front plate from left and right hooks.
3 Hold the left edge and right edge of front plate to lift up front plate from hooks.
Hook
Lift up
Screws
14.2 Test Run
1 Fill up the Tank Unit with water. For details refer to Tank Unit installation instruction and operation instruction.
2 Set ON to the Indoor Unit and RCCB/ELCB. Then, for control panel operation please refers to air-to-water
heatpump operation instruction.
3 For normal operation, pressure gauge reading should be in between 0.05 MPa and 0.3 MPa.
4 After test run, please clean the Water Filter Set. Reinstall it after finish cleaning.
14.3 Expansion Vessel Pre Pressure Checking
[Lower limit water volume of the system]
Please ensure the capacity of the circulating water of the total system including the capacity of the indoor unit is more
than 50 L.
If the water capacity is insufficient, during deice operation, the water temperature is lowered and the water will freeze
in the system’s component leading to product failure.
[Upper limit water volume of the system]
The indoor unit has a build-in Expansion Vessel with 10 L air capacity and initial pressure of 1 bar.
Total amount of water in the system should be below 260 L. If the total amount of water is more than 260 L, please
add expansion vessel (field supply). The expansion vessel capacity required for the system can be calculated from
the formula below.
V =
×
Vo
Ɛ
1 -
98 +
P
1
98 +
P
2
V : Required gas volume
<expansion vessel volume L>
V
O
: System total water volume <L>
Ɛ
: Water expansion rate 5
→
60
˚
C = 0.0171
P
1
: Expansion tank filling pressure = (100) kPa
P
2
: System maximum pressure = 300 kPa
-
( ) Please confirm at actual place
-
The gas volume of the sealed type expansion
vessel is presented by <V>.
It’s advised to add 10% margin for required gas
volume of calculation.
Water expansion rate table
Water temperature (°C)
Water expansion rate
Ɛ
10 0.0003
20 0.0019
30 0.0044
40 0.0078
50 0.0121
60 0.0171
70 0.0228
80 0.0291
90 0.0360
[Adjustment of the initial pressure of the expansion
vessel when there is a difference in installation height]
If the height difference between the indoor unit and
the highest point of the system water circuit (H) is
more than 7m, please adjust the initial pressure of the
expansion vessel (Pg) according to the following
formula.
Pg= (H*10+30) kPa