EWAQ+EWYQ005~007ACV3P
Packaged air-cooled water chillers and
packaged reversible air to water heat pumps
4PW33165-1D
Installation manual
7
Connecting the water circuit
Water connections must be made in accordance with the installation
drawing delivered with the unit, respecting the water in- and outlet.
If dirt 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 so that no
dust and dirt enter.
■
Use a good thread sealant for the sealing of the connections.
The sealing must be able to withstand the pressures and
temperatures of the system, it must also be resistant to the used
glycol in the water.
■
When using non-brass metallic piping, make sure to insulate
both materials from each other to prevent galvanic corrosion.
■
Because brass is a soft material, use appropriate tooling for
connecting the water circuit. Inappropriate tooling will cause
damage to the pipes.
Protecting the water circuit against freezing
Frost can damage the unit. For this reason, in colder climates the
water circuit must be protected by means of a heater tape or by
adding glycol to the water.
In case of heater tape
1
Check that the unit has the option heater tape installed.
(Connections of the factory mounted heater tape are made on
terminals 4/5 inside the switch box).
2
Install a heater tape (field supply) on the outdoor field piping.
Power supply connections for this heater tape must be made on
terminals 4/5 inside the switch box provided this heater tape is of
a type that consumes not more than 200 W.
In case of glycol
Depending on the expected lowest outdoor temperature, make sure
the water system is filled with a weight concentration of glycol as
mentioned in the table below.
Also refer to
"Checks before start-up" on page 11
Initial start-up at low ambient temperatures
Charging the water
1
Connect the water supply to the drain and fill valves (see
).
2
Fill with water until the manometer indicates a pressure of
approximately 2.0 bar. Remove air in the circuit as much as
possible using the air purge valves.
Be careful not to deform the unit piping by using excessive
force when connecting the piping.
1
To secure the piping of the unit
2
To connect the shut-off valve
3
Water inlet
4
Water outlet
1
2
3
4
For the heater tape to operate, power to the unit must
be provided and the main isolator switch must be on.
For this reason never disconnect power and never
turn off the main isolator switch for a long time during
cold periods!
In case this heater tape is of a type that consumes
more than 200 W, this heater tape must be connected
to a separate power supply and not to heater tape
terminals 4/5!
Minimum
outdoor temperature
0°C
–5°C
–10°C
–15°C
Ethylene glycol
10%
15%
25%
35%
Propylene glycol
10%
15%
25%
35%
NOTE
To ensure that the unit operates within its operating
range as soon as possible (water temperature >30°C),
the load during start-up must be reduced as much as
possible. For example you can do this by putting off
fans of the fan coil units until the water temperature
has increased to 30°C.
NOTE
■
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 to avoid air entering the
circuit.
■
The unit might dispose some excessive water
through the pressure relief valve.
