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2) Pipeline Size
To ensure the best performance, the pipe size should be selected according to the specific
installation needs. The following are the recommended pipe sizes.
Hot water pipe: Main pipe –Rp 3/4" (20mm)
Cold water pipe: The size of the cold-water pipe should be the same or larger than the size
of the hot water pipe used.
3) Cold water connection
The cold-water inlet is at lower part of the water heater and should be directly connected
with tap water. As shown in the figure, first connect a shut-off valve, then connect a
non-return valve on the side close to the heater, and finally connect a union.
If supply water pressure exceeds the rated max. pressure (680 kPa) as stipulated in the
label, a pressure limiting valve shall be connected after the non-return valve. If supply
water quality does not meet the specific water quality requirements, an expansion control
valve shall be used.
4) Hot water connection
The hot water supplied by the water heater has a relatively high temperature and cannot
be used directly for washing. It must be mixed with cold water. Therefore, the cold and hot
water mixing valve should be installed at the hot water use point.
If the hot water outlet of the water heater is too far away from the hot water use point
(more than 12 meters), it is recommended that the hot water pipe be insulated with heat
insulating materials to reduce the waste of hot water and electricity.
5) Water supplied by tank
If cold water is supplied by tank on the top floor, be noted that cold water connection
should meet the following requirements:
The tank shall be at least 1m higher than the highest hot water outlet. If the distance
between the bottom of the domestic tank and the highest hot water outlet is less than 5
meters, precaution should be taken into consideration to avoid air locks in the hot water
pipe. The shut-off valve in cold water pipeline shall be changed to gate valve, which shall
be fully open to ensure the full flow of cold water inlet.
