Daikin EWAT016CZN-A1, Installation, Maintenance And Operation Manual

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EWYT~CZ / EWAT~CZ DEIMHP0140521_00EN
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1.2. General description
All EWYT~CZ / EWAT~CZ machines are built in accordance with the
main European Directives (Machinery Directive, Low Voltage
Directive, Electromagnetic Compatibility Directive, Pressure
Equipment Directive.
The unit purchased is a Heat Pump, that is a machine designed to
cool/heat the water (or a water-glycol mixture) within certain limits
which will be listed below. The unit operates based on the
compression, condensation and evaporation of the coolant gas as
per the Carnot cycle, and is composed mainly of the following parts
depending on the Mode of Operation.
Cooling or Conditioning Mode:
■
One or more scroll compressors which increase the pressure of
the refrigerant gas from evaporation pressure to condensation
pressure.
■
A condenser where the refrigerant gas condenses under high
pressure and transfers heat to the air.
■
An expansion valve which allows the pressure of condensed li-
quid refrigerant to be reduced from condensation pressure to
evaporation pressure.
■
An evaporator, where the low-pressure liquid refrigerant evapo-
rates and chills the water.
Heating Mode or Heat Pump:
■
One or more scroll compressors which increase the pressure of
the refrigerant gas from evaporation pressure to condensation
pressure.
■
A condenser where the refrigerant gas condenses under high
pressure and transfers heat to the water.
■
An expansion valve which allows the pressure of condensed li-
quid refrigerant to be reduced from condensation pressure to
evaporation pressure.
■
An evaporator, where the low-pressure liquid refrigerant evapo-
rates.
■
The operation of the heat exchangers can be inverted using the
4way valve, with which the use of the heating/cooling unit can be
seasonally inverted.
All units are fully assembled in the factory and tested before shipping.
The EWYT~CZ / EWAT~CZ range consists of models with a single
cooling circuit and models with two cooling circuits.
The machine uses R32 refrigerant fluid suitable for the entire field of
application of the machine.
The controller is prewired, set up and tested at the factory. Only
normal field connections such as piping, electrical connections and
pump interlocks are required, simplifying installation and increasing
reliability. All safety and operation control systems are installed at the
factory in the control panel.
The instructions in this manual are applicable to all models in this
series unless otherwise specified.
1.3. Information about the refrigerant
This product contains R32 refrigerant that has a minimal environmental
impact, thanks to its low value of Global Warming Potential (GWP).
According to ISO 817, R32 refrigerant is classified as A2L, which is
slightly flammable, since the flame propagation rate is low, and
nontoxic.
R32 refrigerant can burn slowly when all the following conditions are
present:
■
The concentration is between the lower and upper flammability
limit (LFL & UFL).
■
Wind velocity<propagation of flame velocity
■
Energy of the ignition source>Minimum ignition energy
But pose no risk under the normal usage conditions for airconditioning
equipment and work environment.
Safety class (ISO 817) A2L
PED Group 1
Practical limit (kg/m3) 0.061
ATEL/ ODL (kg/m3) 0.30
LFL (kg/m3) @ 60°C 0.307
Vapor density @25°C, 101.3 kPa (kg/m3) 2.13
Molecular mass 52.0
Boiling point (° C) -52
GWP (100 yr ITH) 675
GWP (ARS 100 yr ITH) 677
Autoignition temperature (° C) 648
Table 1 – Physical properties of R32 refrigerant
1.4. Installation information
The heat pump must be installed in open air or machinery room
(location classification III).
To ensure location classification III a mechanical vent on the
secondary circuit(s) must be installed.
Local building codes and safety standards shall be followed; in
absence of local codes and standards refer to EN 378 3 / ISO 5149-3
as a guide.
In paragraph “Additional guidelines for safe use of R32” there are
provided additional information that should be added to the
requirements of safety standards and building codes.
Additional guidelines for safe use of R32 for equipment located in
the open air
Units sited in the open air shall be positioned to avoid leaked
refrigerant flowing into a building or otherwise endangering people
and property.
The refrigerant shall not be able to flow into any ventilation fresh air
opening, doorway, trap door or similar opening in the event of a leak.
Where a shelter is provided for refrigerating equipment sited in the
open air it shall have natural or forced ventilation.
For units installed outside in a location where a release of refrigerant
can stagnate e.g. below ground, then the installation shall comply
with the requirements for gas detection and ventilation of machinery
rooms.
Additional guidelines for safe use of R32 for equipment located in
a machinery room
When a machinery room is chosen for the location of the unit it shall
be in accordance with local and national regulations. The following
requirements (according to EN 378-3:2016) can be used for the
assessment.
■
A risk analysis based on the safety principle for a refrigeration
system (as determined by the manufacturer and including the
charge and safety classification of the used refrigerant) should
be conducted to determine if it is necessary to install the heat
pump in a separate refrigeration machinery room.
■
Machinery rooms should not be used as occupied spaces. The
building owner or user shall ensure that access is permitted only
by qualified and trained personnel doing the necessary mainte-
nance to the machinery room or general plant.
■
Machinery rooms shall not be used for storage except for tools,
spare parts and compressor oil for the installed equipment. Any