Gree GRS-CQ12Pd/NhG-K, Owner'S Manual

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Air-to-water Heat Pump
22
MONOBLOC TYPE
After filling is finished, please do the leakage detection before test running; another time of leak detection should
be done when it’s removed.
(6) Safety instructions for transportation and storage
Please use the flammable gas detector to check before unload and open the container.
No fire source and smoking.
According to the local rules and laws.
7. Installation of Hydraulic Unit
7.1 Available External Static Pressure of Outlet
Note
(a) See the curve above for the maximum external static pressure. The water pump is of variable frequency.
And during operation, the water pump will adjust its output based on the actual load.
7.2 Water volume and expansion vessel pressure
Notes
(a) The expansion vessel is 2 liter and 1.5bar pre-pressurized for 4/6/8kW unit; 3 liter and 1.5bar per-
pressurized for 10/12/14/16kW unit ;
(b) Total water volume of 44 liter is default for 4/6/8kW unit and 66 liter for 10/12/14/16kW unit; if total water is
changed because of installation condition, the pre-pressure should be adjusted to secure proper operation. If
the unit is located at the highest position, adjustment is not required;
(c) Minimum total water volume is 20 liter;
(d) To adjust pre-pressure, use nitrogen gas by certificated installer.
7.3 The method of calculating the charging pressure of expansion vessel
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:
Bar(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