KKT chillers vBoxX 10, Инструкция по эксплуатации

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2.2. Evaporator
The evaporator is a plate heat exchanger, which transfers heat from the cold water to the
refrigerant. In order for the heat transfer to take place, the refrigerant in the evaporator has a lower
temperature than the cold water and when it absorbs heat its aggregation state changes from liquid
to gaseous. If the cold water is contaminated with dirt, deposits can form on the transfer surfaces
of the evaporator. These worsen heat transfer to the refrigerant and have a negative effect on the
machine's refrigeration capacity. For this reason you must always pay attention to the specified
water quality and must not use any additives other than those specified.
2.3. Condenser
The condenser is a microchannel heat exchanger, which transfers heat from the refrigerant to the
ambient air. In order for the heat transfer to take place, the refrigerant in the condenser has a
higher temperature than the drawn-in ambient air and when it transfers heat its aggregation state
changes from gaseous to liquid.
Contaminated cooling air can cause deposits to form on the condenser's surface over time. This
has a negative effect on heat transfer to the refrigerant. This limits the machine's use limit and also
reduces the machine's refrigeration capacity. How to clean the condenser is described in
Chapter
9 Cleaning . If you operate your chiller in an environment contaminated with dust or oil vapour, use
the optionally available air filter mat (see Chapter 3.24 Air filter mat).
If a cooling water system is available and the hot waste air of the chiller is to be avoided, the chiller
can also be designed with a water-cooled condenser
(see Chapter 3.3 Version with water-cooled
condenser ).
2.4. Expansion valve
The expansion valve controls the liquid refrigerant impinging the evaporator and at the same time
controls the refrigerant load before it enters the evaporator. This flow restriction causes the
refrigerant to cool to the evaporation temperature.
The expansion valve used in your machine is controlled electronically. The electronic control
ensures that the evaporator is always optimally loaded with refrigerant. This improves the COP
(coefficient of performance) and reduces pressure fluctuations in the refrigeration cycle.
2.5. Refrigerant
The refrigerant R410A circulates in the refrigeration circuit. It "transports" heat from the evaporator
to the condenser and in doing so changes its aggregation state continuously.
R410A is a fluorinated greenhouse gas consisting of the zeotropic mixture of 50% R32 and 50%
R125 with virtually negligible glide. R410A has a very high volumetric refrigerating capacity and has
no ozone depletion potential (ODP=0). A corresponding safety data sheet can be requested from
our KKT chillers service team (
see Table 1: Contact details ).