■
Be aware of the hygroscopic property of glycol: it absorbs
moisture from its environment.
■
Leaving the cap off the glycol container causes the
concentration of water to increase. The glycol
concentration is then lower than assumed. And in
consequence, freezing can happen after all.
■
Preventive actions must be taken to ensure minimal
exposure of the glycol to air.
Also refer to "Pre-operation checks/Checks before initial start-up"
5.7 Filling water
1. Connect the water supply to the fill value and open the value.
2. Make sure the automatic air purge valve is open (at least 2 turns).
3. Fill with water until the manometer indicates a pressure of
approximately 2.0 bar(g). Remove air in the circuit as much as
possible using the air purge valves. Air present in the water circuit
might cause malfunctioning of the backup heater.
During filling, it might not be possible to remove all air in
the system. Remaining air will be removed through the
automatic air purge valves during first operating hours of
the system. Additional filling with water afterwards might be
required.
■ The water pressure indicated on the manometer will vary
depending on the water temperature (higher pressure at
higher water temperature).
However, at all times water pressure should remain
above 0.3 bar(g) to avoid air entering the circuit.
■ The unit might dispose some excessive water through
the pressure relief valve.
■ Water quality must be according to "Safe Drinking water
Act "
5.8 Piping insulation
The complete water circuit including all piping, must be insulated to
prevent condensation during cooling operation and reduction of the
heating and cooling capacity as well as prevention of freezing of the
outside water piping during winter time. The thickness of the sealing
materials must be at least 13 mm with λ= 0.039 W/mK in order to
prevent freezing on the outside water piping.
If the temperature is higher than 30°C and the humidity is higher than
RH 80%, then the thickness of the sealing materials should be at
least 20 mm in order to avoid condensation on the surface of the
sealing.
NOTE
NOTE
5.9 Field wiring
■ A main switch or other means for disconnection, having a
contact separation in all poles, must be incorporated in the
fixed wiring in accordance with relevant local laws and
regulations.
■ Switch off the power supply before making any
connections.
■ Use only copper wires.
■ Never squeeze bundled cables and make sure that it does
not come in contact with the piping and sharp edges.
Make sure no external pressure is applied to the terminal
connections.
■ All field wiring and components must be installed by a
licensed electrician and must comply with relevant local
laws and regulations.
■ The field wiring must be carried out in accordance with the
wiring diagram supplied with the unit and the instructions
given below.
■ Be sure to use a dedicated power supply. Never use a
power supply shared by another appliance.
■ Be sure to establish a ground. Do not ground the unit to a
utility pipe, surge absorber, or telephone ground.
Incomplete ground may cause electrical shock.
■ Be sure to install a ground fault circuit interrupter (30 mA).
Failure to do so may cause electrical shock.
■ Be sure to install the required fuses or circuit breakers.
5.9.1 Precautions on electrical wiring work
■ Fix cables so that cables do not make contact with the pipes
(especially on high pressure side).
■ Secure the electrical wiring with cable ties as shown in figure
so that it does not come in contact with the piping, particularly on
the high-pressure side.
■ Make sure no external pressure is applied to the terminal
connectors.
■ When installing the ground fault circuit interrupter make sure that
it is compatible with the inverter (resistant to high frequency
electrical noise) to avoid unnecessary opening of the ground fault
circuit interrupter.
The ground fault circuit interrupter must be a high- speed
type breaker of 30 mA (<0.1 s).
■ As this unit is equipped with an inverter, installing a phase
advancing capacitor not only will deteriorate power factor
improvement effect, but also may cause capacitor abnormal
heating accident due to high-frequency waves. Therefore, never
install a phase advancing capacitor.
5.9.2 Overview
The illustration below gives an overview of the required field wiring
between several parts of the installation. Refer also to "TYPICAL
APPLICATION EXAMPLES".
19
WARNING
NOTE
V.1