Note: Before performing any maintenance and repair to the unit, please cut off power
supply. Electricity leakage will cause body injury.
In order to exert the unit's performance fully, must pay attention to the following items:
a. Electric connection: The cables for communication must be shielded and protected by
means of single-end earthing. Wiring of communication cables together with power cables is
prohibited. the power supply provided should be within the compressor permitted range. Confirm
there is no wrong connection in terminals and the main panel of AC contact, etc. Confirm all the
electric connections are not loose; all the electric components (AC contactor and relay, etc.) are
connected firmly and safely. Especially pay attention to the condition of the connecting wire between
control components and electric control box and power cord. The power wire shall not be warped,
and the insulation cover shall not have cracks and cut. Check the energy consumption in starting and
operating the unit is in the permitted range.
b. Water system connection: confirm the water system does not leak water. If the unit has not been
used for a long period, it is necessary to open the drain valve of the water pump to empty the water pump,
tube pipe or shell pipe type heat exchanger and all the water in the pipes. If the ambient temperature
may drop below 0℃, it is more necessary to be done. If the water in the unit is not emptied, the main
switch of the power supply must keep close, and the unit is set in heating mode, thus it can prevent from
freezing by the heating temperature sensor. Do be careful when cleaning the filter
c. Cleaning of tube in tube (shell&tube) heat exchanger: when using the unit, for example,
when using hard water, sometimes it will produce dirty. In this condition, it is recommended to
install the filter to remove dirty. The heat exchanger shall use cleaning solution to be washed; the
solution can be weak acid solution, use pump to drive the cleaning solution in the heat exchanger.
In order to fulfill a better cleaning effect, the circulation flow speed of the acid solution shall be
1.5 times of normal water flow, if can use acid solution to wash the pipe in an opposite direction
again, the effect will be better. Finally, use a large amount of water to repeatedly wash the acid
solution clean. The unit shall be cleaned periodically, not until the unit is blocked. The cleaning
frequency is determined by the water quality being used, but generally, once a year is rather
d. Refrigerant circuit: Confirm the refrigerant and refrigerant oil does not leak from the
compressor. Check if the pressure in the high/low pressure side is normal. Check the inside cleanness
of the plate type heat exchanger by pressure drop.
e. Control: Check and the location of the total return water temperature sensor and the temperature
difference, and then make adjustments accordingly. Check the operation of all relays, high/low pressure
protection device and controls.