4. WATER PIPE WORK
Never use heating mediums other than water in cold-hot water or chilled water. Use of other mediums can cause
fires or explosions.
Always use cold-hot water or chilled water that complies with water quality standards. Deterioration in water
quality can cause breakdowns, water leakage and other problems.
Dispose of brine, cleaning solvents and other waste in accordance with legal stipulations. Illegal disposal not
only violates the law, but can also have a negative impact on the environment.
1. Water pipes may be connected to either the front or the rear of the water heat exchanger unit. Rubber stoppers
are attached to the connecting ports at the time of shipping. Place the accessory plug in connecting port that
is not in use.
2. Install the cold-hot water circulation pump at the water heat exchanger unit inlet pipe side.
3. Water pipe caliber should be equal to or above the connecting port caliber (50A), with as little bending as
possible to reduce pipe resistance. In addition, use union joints or flange joints close to the unit, enabling easy
detachment.
4. Attach appropriate water and air discharge valves to
the water pipes. Allowing air to be mixed into the fluid
inside the pipes can cause noise, corrosion and
declines in capacity.
5. Keep the level of water stored inside the system
above the minimum storage volume.
When the storage water level is low, install a storage
tank or other equipment.
Inadequate amounts of storage water can result in
frequent unit starting and stopping and become the
cause of breakdowns.
6. For test operation, attach a water temperature gauge
and flow rate adjustment valve to the water pipe,
enabling flow rate adjustments in cold water
(hot water) to be made while checking the water
temperature gauge.
Do
not touch the adjustment valve once adjustments
have been made.
7. Perform adjustments so that the hydraulic pressure
on the water heat exchanger unit is no more than
0.7MPa.
8. Always attach an expansion tank inside the water
pipe system.
9. For cold-hot water circulation volume (water volume),
operate within the range listed in Fig. 8. Use outside
of this range can cause accidents due to corrosion
or freezing in the heat exchanger.
8
10. Always perform adequate cooling and heat insulation
work on the water pipes.
Inadequate insulation work can result in heat loss, and
also poses the threat of breakage caused by freezing
during severe winter cold.
Cold-hot water flow rate (m
3
/h)
Hydraulic loss (kPa)
25
20
15
10
5
0
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
minimum
requid
flow rate
standard
flow rate
Maximum
allowable
flow rate
S-250WX2E5
Cold-hot water flow rate (m
3
/h)
Hydraulic loss (kPa)
25
20
15
10
5
0
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
minimum
requid
flow rate
standard
flow rate
Maximum
allowable
flow rate
S-500WX2E5
Cold-hot water flow rate (m
3
/h)
Hydraulic loss (kPa)
25
30
20
15
10
5
0
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
minimum
requid
flow rate
standard
flow rate
Maximum
allowable
flow rate
S-710WX2E5
Fig.8 Hydraulic Loss Characteristics
