SPACE HEATING AND DHW
9)
Check Water Volume:
The unit has a built-in 8L expansion vessel, and default initial
pressure is 1 bar. To ensure the unit works normally, the
initial pressure of expansion vessel should be adjusted
according to the circulated water volume.
•
Use water volume checklist below to decide whether initial
pressure of expansion vessel needs to be adjusted.
•
Use water volume checklist to confirm the total volume of
water in installation system is below the allowed maximum
water volume.
•
Installation height difference: height difference between
highest point of water circulation and the unit. If the unit is
mounted at the highest point, above all water pipes, the
installation height is deemed to be 0 m.
•
Calculate initial pressure of expansion vessel. Decide initial
pressure (Pg) according to the maximum installation height
difference (H), seen below:
Pg=H/10+0.3
Unit: H (m), Pg (bar)
Water Volume Checklist
Installation
height
difference (a)
≤7m
Safety V alve
(3 bar)
>7m
Maximum Water Volume Curve Graph
≤220L
No need to adjust initial pressure of
expansion vessel
Things need to do :
Must increase initial pressure.
Calculate it based on the section
"Check water volume". Ensure water
volume is lower than allowed maximum
water volume (using the figures below).
2.8
2.3
1.8
1.3
0.8
0.3
0
50
100
150
Maximum Water Volume(L)
17
The process of calculating allowed maximum water volume
•
in whole circulation is:
- Calculate maximum water volume corresponding to initial
pressure Pg by using maximum water volume curve as
shown below.
- Confirm the total maximum water volume in water circulation
is smaller than above value. Otherwise, the expansion
vessel in the unit is smaller for system.
?
N O T E
•
0.3 bar is the minimum initial pressure and 1.5 bar is the maximum
initial pressure of expansion vessel set outside the factory.
•
When initial pressure in expansion vessel is set as 0.3 bar at
minimum, the water quantity required by system is higher than the
limit value, it may be considered replacing expansion vessel with
bigger volume.
Water Volume
Things need to do :
Must reduce initial pressure.
Calculate it based on the section "Check water
volume". Ensure water volume is lower than
allowed maximum water volume (using the
figures below).
The expansion vessel is too small to install.
(It needs proper expansion vessel or use
safety valve with high activated pressure
that is supplied from local place)
200
250
300
350
>220L