Hisense Hi-Therma Series Service Handbook page 199

Installation
● If DHW tank is not used for more than 2 weeks, a
certain amount of hydrogen will gather in DHW tank. It is
recommended to open temperature pressure valve handle or
water outlet faucet for several minutes to release hydrogen.
However, do not open hot water faucet in dishcleaning machine
and washing machine, etc. When hydrogen is released, do not
make open flame or operate other electrical apparatus. When
gas is released, releasing sound will be heard.
●
Temperature pressure valve is used to prevent too high
temperature in DHW tank (higher than 94°C, recommended)
and water pressure (higher than 0.85MPa, recommended).
2 Temperature protection switch
● When using the DHW electric heater, an Auto Restore
Temperature Protection Switch (THe2) has to be
installed to prevent the DHW temperature from being
heated uncontrollable. When DHW temperature
exceeds the protection value, the temperature
protection switch opens, and auto restores when
DHW temperature reduces below the protection value.
The protection value can be selected according to
temperature requirement of DHW. The recommended
protection value is 80°C.
● Temperature Protection Switch / Temperature fuse
(THe1) is connected in the DHW electric heater power
supply circuit, which can directly cut off the power
supply of DHW electric heater when DHW temperature
exceeds the protection value. The recommended
protection value is 90°C.
● The detail wiring diagram of DHW tank is shown in
section "8.3.10.3.3 Wiring of DHW electric heater".
●
Do not install DHW electric heater without temperature
protection device.
● Electrical box cover must be opened by qualified electrician.
●
Power off before open electrical box cover.
8.3.9.4.3 DHW TANK INSTALLATION
●
Recommend installing this equipment to balcony or outdoor at
temperature from 0 °C to 43 °C.
● DHW tank is mounted near floor drain to connect temperature
pressure valve drainage pipe.
●
Do not install DHW tank in place with corrosive gas.
● Installation location is free from frosting.
●
Installation location must bear weight of DHW tank containing
water.
● Ensure dimension of water pipe is above 1 inch (recommend
DN40 water pipe), provide enough volume to pipeline and
reduced resistance in pipeline system.
●
DHW tank is located in a place that is convenient for repair and
ensure electrical box is open.
● No accumulated water around installation location.
●
Arrange filter at water inlet pipe, preventing domestic water
contaminated by impurities.
●
Ensure DHW tank is full of water before energizing.
Install DHW tank
(1) Check DHW tank for complete accessories.
(2) When mounted on ground, ensure the bottom of DHW
tank is flat and vertically. If mounted in bath room where
water exists, recommend installing on a foundation
higher than ground, preventing the bottom being soaked
by water.
(3) To ensure the measurement accuracy, the DHW tank
thermistor should be coated with thermal grease. The
water proof cable gland (field supplied) is recommended
to secure the sensor firmly. The DHW tank sensor must
be installed to reach the inner wall of the DHW tank and
keep in good contact with it.
Outer wall of the
DHW tank
Water proof
cable gland
● DHW tank supplies hot water from tap water. Domestic hot
water is only used when tap water is connected.
● For safety, do not add ethylene glycol into water circulation. If
added, water will be contaminated when heat exchanger coil
leaks.
● When water hardness is more than 250-300 ppm, recommend
using softened water to reduce DHW tank scale.
● softened water to reduce DHW tank scale.
Immediately flush DHW tank with fresh water after installation.
Flush once every day in first five days of installation.
● Try to avoid long runs of water piping between the tank and
the DHW installation in order to decrease possible temperature
losses. lf the domestic cold water entry pressure is higher than
the DHW tank's design pressure, a pressure reducer must be
fitted.
● After used for a while (depend on local water quality and use
frequency), clean DHW tank and remove scales.
a. Power off and close water inlet valve.
b. Open water outlet valve and drainage valve to empty DHW
tank.
When scales are removed, temperature in DHW tank may be a little
high, it should prevent burns or drainage equipment damaged.
c. Close drainage valve after cleaning several minutes with
water inlet valve opened. Ensure effluent water is closed
after DHW tank is full of water. Power on and get back to
work.
●
Always check DHW tank and its surroundings has accumulated
water or not. If leak, contact local dealer.
178
Inner wall of
the DHW
tank
DHW tank thermistor
Thermal grease