Sinclair GSH-60IRA series Operational Manual page 26

To adjust pre-pressure, use nitrogen gas by certificated installer.
9.7 The method of calculating the charging pressure of expansion vessel
needed to be adjusted is as follows.
During installation, if the volume of water system has changed, please check if the
pre-set pressure of the expansion vessel needs to be adjusted according to the following
formula:
（H ---the difference between installing location of indoor unit and the highest spot of water
system.）
Ensure that the volume of water system is lower than the maximum volume required in
the above figure. If it exceeds the range, the expansion vessel does not meet the
installing requirement.
Installation height
difference
＜7 m
＞7 m
1
Note：Installation height difference ：-the difference between installing location of indoor
unit and the highest spot of water system；if the indoor unit is located at the highest point
of the installation，the installation height difference is considered 0m；
Example 1： The indoor unit is installed 5m below the outdoor unit and the total volume of the
water system is 100L.
Referring to the above figure, it is not necessary to adjust the pressure of the expansion
vessel.
Example 2：The indoor unit is installed on the highest spot of the water system and the total
water volume is 350L.
1. As the volume of water system is higher than 280L, it is necessary to adjust the
pressure of the expansion vessel be lower.
2. The formula of calculating pressure
3. The maximum volume of the water system is about 410L. As the actual volume of
the water system is 350L, the expansion vessel meets the installing requirement.
4. Adjust the pre-set pressure of the expansion vessel from 1.0Bar to 0.3Bar.
AIR-TO-WATER HEAT PUMP INSTALLATION MANUAL
=
P H
( /10 0.3)
g
1
＜280L
Adjustment is not necessary
1. Pre-set pressure needs to be
adjusted according to the above
formula.
2. Check if the water volume is
lower than the maximum water
volume. (with help of the above
figure)
= +
P H
( /10 0.3) (0 /10 0.3) 0.3
g
24
+
Bar
Water volume
1. Pre-set pressure needs to be
adjusted according to the above
formula.
2. Check if the water volume is
lower than the maximum water
volume. (with help of the above
figure)
The expansion vessel is too small
and adjustment is not available.
= + =
＞280L
Bar