Thermal Care Accuchiller EQ Series, Руководство по установке и эксплуатации

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18
Operate the system for approximately 30 minutes.
Check the liquid line sight glass. The refrigerant flow
past the sight glass should be clear. Bubbles in the
refrigerant indicate either low refrigerant charge or
excessive pressure drop in the liquid line. Indications
of a shortage of refrigerant are low operating
pressures and subcooling. Normal subcooling ranges
are from 10°F to 20°F. If it is not, check the superheat
and adjust if required. The superheat should be
approximately 10°F. Since the unit is factory charged,
adding or removing refrigerant charge should not be
necessary. If the operating pressures, sight glass,
superheat, and subcooling readings indicate a
refrigerant shortage, charge refrigerant as required.
With the unit running, add refrigerant vapor by
connecting the charging line to the suction service
valve and charging through the backseat port until
operating conditions become normal.
CAUTION: A clear sight glass alone does not
mean that the system is properly charged. Also,
check system superheat, sub-cooling, and unit
operating pressures. If both suction and
discharge pressures are low but sub-cooling is
normal, a problem other than refrigerant
shortage exists. Do not add refrigerant, as this
may result in overcharging the circuit.
After achieving proper flows and temperatures, press
the Stop button. The unit is now ready for service.
Preventive Maintenance
Once your portable chiller is in service, follow the
maintenance procedures shown below as closely as
possible. The importance of a properly established
preventive maintenance program cannot be
overemphasized. Taking the time to follow these
simple procedures will result in substantially reduced
downtime, reduced repair costs, and an extended
useful lifetime for the chiller. Any monetary costs of
implementing these procedures will normally more
than pay for it. The preventative maintenance
checklist in this manual is a great way to log and
keep track of maintenance.
Once a Week
1.
(Air-Cooled Units Only) Check the surface of the
air-cooled condenser coil for dirt and debris. To
clean, rinse thoroughly with water and use a
mild detergent to remove smoke and or grease
stains.
2. Check to make sure that the To Process
temperature is reasonably close to the Set Point
temperature. If the temperature stays more than
5°F away from the set point, there may be a
problem with the chiller. If this is the case, refer
to the Troubleshooting Chart or contact the
Customer Service Department.
3.
Check the pump discharge pressure on the
gauge on the back panel of the chiller.
Investigate further if the pressure starts to stray
away from the normal operating pressure.
4.
Check the coolant level in the reservoir.
Replenish if necessary making sure to take
proper precautions to maintain the appropriate
glycol concentration.
5.
Check coolant circulation pump for leaks in the
seal area. Replace pump seal if necessary.
6.
Check refrigerant sight glass for air bubbles or
moisture indication. If the sight glass indicates
that there is a refrigeration problem, have the
unit serviced as soon as possible.
Once a Month
7.
With the main disconnect shut off and locked
out, check the condition of electrical connections
at all contactors, starters and controls. Check for
loose or frayed wires.
8.
Check the incoming voltage to make sure it is
within 10% of the design voltage for the chiller.
9.
Check the amp draws to each leg of the
compressor (fans or blowers on air-cooled units)
and pump to confirm that they are drawing the
proper current.
Every Three Months
10.
Units are equipped with a Y-strainer between
the return connection and the evaporator inlet.
Remove and clean the strainer basket if
necessary. This may be required more often if
contaminants can easily get into the coolant.
11.
Have a qualified refrigeration technician inspect
the operation of the entire unit to ensure that