HTW A60CGN8PLUS Manuel De L'utilisateur page 109

8.5.3 Water circuit connection
Water connections must be made correctly in accordance with labels on the indoor unit, with respect to the water inlet and water outlet.
Be careful not to deform the unit's piping by using excessive force when connecting the piping. Deforming the piping can cause the
unit to malfunction.
If air, moisture or dust gets in the water circuit, problems may occur. Therefore, always take into account the following when connecting
the water circuit:
Use clean pipes only.
Hold the pipe end downwards when removing burrs.
Cover the pipe end when inserting it through a wall to prevent dust and dirt entering.
Use a good thread sealant for sealing the connections. The sealing must be able to withstand the pressures and temperatures of the
system.
When using non-copper metallic piping, be sure to insulate two kind of materials from each other to prevent galvanic corrosion.
As copper is a soft material, use appropriate tools for connecting the water circuit. Inappropriate tools will cause damage to the pipes.
The unit is only to be used in a closed water system. Application in an open water circuit can lead to excessive corrosion of the
water piping:
Never use Zn-coated parts in the water circuit. Excessive corrosion of these parts may occur as copper piping is used in the
unit's internal water circuit.
When using a 3-way valve in the water circuit. Preferably choose a ball type 3-way valve to guarantee full separation between
the domestic hot water and floor heating water circuit.
When using a 3-way valve or a 2-way valve in the water circuit. The recommended maximum changeover time of the valve
should be less than 60 seconds.
8.5.4 Water circuit anti-freeze protection
All internal hydronic parts are insulated to reduce heat loss. Insulation must also be added to the field piping.
The software contains special functions using the heat pump and backup heater (if it is aviliable) to protect the entire system against
freezing. When the temperature of the water flow in the system drops to a certain value, the unit will heat the water, either using the heat
pump, the electric heating tap, or the backup heater. The freeze protection function will turn off only when the temperature increases to a
certain value.
In event of a power failure, the above features would not protect the unit from freezing.
When the unit is not running for a long time,make sure the unit is powered on all the time,if you want to cut off the power,the water
in the system pipe needs to be drained clean,avoid the pump and pipeline system be damaged by freezing.Also the power of the
unit needs to be cut off after water in the system is drained clean.
CAUTION
NOTE
CAUTION
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