frost-trol GREGAL, Руководство по установке и обслуживанию

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INSTALLATION AND MAINTENANCE MANUAL
TRANSLATION OF THE
ORIGINAL DOCUMENT
For additional copies visit:
www.frost-trol.com
GREGAL SOLID LINES
D008270 Versión: 2 -18-
2.6. REFRIGERATING SYSTEM CONNECTION
The refrigerated display cabinet described in this manual does not include a
condensing unit, but is provided with the necessary connections to be connected to
the existing cooling circuit.
It is the responsibility of the installer to establish a cooling system that is capable
of providing the cooling capacity demanded by the cabinet taking into account both
the size of the case and the distance to the cooling system.
2.7. INSTALLATION’S DRYING
The evaporators are pressurised with N
2
at 20±0,5 bar. Check this
value before depressurising.
If this is not the case then do not actuate the cabinet and contact the
Frost-Trol technical department within 72 hours.
The refrigerated cabinet must be dehydrated in avacuum and at the unit's normal
operating pressure.
Poor dehydration causes breakages of the evaporator's
solder joints at the bends, because the humidity at different
points in the refrigeration cycle condenses into micro drops
of H
2
O which then get deposited and accumulate in the
solder joint cracks on the low pressure side. When the H
2
O
changes state into a solid, this causes a protuberance on
the outside of the copper piping that will eventually break,
causing a leak.
Before turning on the installation, check meticulously the circuit’s sealing verifying
the screw’s tighten of the thermostatic expansion’s valve and the Schrader valve.
2.8. THERMOSTATIC VALVE CONTROL
In order to obtain maximum evaporator efficiency, the expansion valves should be
adjusted to have a reheating value of 3 to 6 degrees.
When viewed from the front, the expansion valve is situated on the far left of the
unit.To ascertain the reheating value measure the evaporation pressure on the
Schrader valve, which is located on the unit. Read the pressure on the pressure
gauge, which also displays the temperature, Te, that corresponds to the
evaporation pressure.
Measure the exact aspiration line temperature using the thermocouple in front of
the thermostatic expansion valve bulb. This will ensure that you obtain the
temperature of the evaporator's exit, Tse. The difference between the two
temperatures is the reheating value, Tr, in the evaporator:
Tse-Te=Tr
To adjust the reheating remove the cap from the thermostatic expansion valve
reheating screw and turn it anti-clockwise to lower the reheating, or clockwise to
increase the reheating.