Water Treatment; Evaporator And Recovery Exchangers Anti-Freeze Protection; Installing The Flow Switch; Table 1 - Acceptable Water Quality Limits - Daikin EWYD-BZ Series Installation, Maintenance & Operation Manual

Install a mechanical filter on the inlet to each heat exchanger. Failure to install a mechanical filter allows solid particles
and/or welding slag to enter the exchanger. Installation of a filter having a mesh size not exceeding 0,5 – 1 mm is
advised.
The manufacturer cannot be held responsible for any damage to exchangers ensuing from the lack of a mechanical filter.

Water treatment

Before putting the machine into operation, clean the water circuit. Dirt, scale, corrosion residue and other foreign material
can accumulate inside the heat exchanger and reduce its heat exchanging capacity. Pressure drop can increase as well,
thus reducing water flow. Proper water treatment therefore reduces the risk of corrosion, erosion, scaling, etc. The most
appropriate water treatment must be determined locally, according to the type of system and local characteristics of the
process water.
The manufacturer is not responsible for damage to or malfunctioning of equipment caused by failure to treat water or by
improperly treated water.

Table 1 - Acceptable water quality limits

pH (25°C)
Electrical conductivity S/cm (25°C)
Chloride ion (mg Cl
Sulphate ion (mg SO
Alkalinity (mg CaCO

Evaporator and recovery exchangers anti-freeze protection

All evaporators are supplied with a thermostatically controlled anti-freeze electrical resistance, which provides adequate
anti-freeze protection at temperatures as low as –25°C. However, unless the heat exchangers are completely emptied
and cleaned with anti-freeze solution, additional methods should also be used against freezing.
Two or more of below protection methods should be considered when designing the system as a whole:
12 Continuous water flow circulation inside piping and exchangers
13 Addition of an appropriate amount of glycol inside the water circuit
14 Additional heat insulation and heating of exposed piping
15 Emptying and cleaning of the heat exchanger during the winter season
Partial heat recovery heat exchangers (desuperheters) are not protected against freezing (no heater is installed).
It is the responsibility of the installer and/or of local maintenance personnel to ensure that two or more of the described
anti-freeze methods are used. Make sure that appropriate anti-freeze protection is maintained at all times. Failure to
follow the instructions above could result in damage to some of the machine's components. Damage caused by freezing
is not covered by the warranty.

Installing the flow switch

To ensure sufficient water flow through the evaporator, it is essential that a flow switch be installed on the water circuit.
The flow switch can be installed either on the inlet or outlet water piping. The purpose of the flow switch is to stop the
machine in the event of interrupted water flow, thus protecting the evaporator from freezing.
The flow switch on the heat recovery circuit prevents the machine from shutting down due to high pressure.
The flow switch must be a paddle-type flow switch that is suitable for heavy-duty outdoor applications (IP67) and pipe
diameters in the range of 1" to 6".
The flow switch is provided with a clean contact which must be electrically connected to terminals 8 and 23 of terminal
board M3 (check the machine's wiring diagram for further information).
The flow switch must be adjusted to intervene (switch off the unit) when the flow rater is lower than no less than 50% of
nominal flow rate.
For further information regarding device installation and settings, please read the instruction leaflet in the device box.
D-EIMHP00508-16EN - 22/64
6,88,0
800
- 200
/ l)
2 -
200
/ l)
4
100
/ l)
3
ATTENTION
Total Hardness (mg CaCO
Iron (mg Fe / l)
Sulphide ion (mg S
Ammonium ion (mg NH
Silica (mg SiO / l)
2
WARNING
 200
/ l)
3
 1.0
2 ­
/ l) None
+
 1.0
/ l)
4
 50