Operation manual
7
LREQ5~20B7Y1
Air cooled refrigeration condensing unit
4PW74303-1C – 2016.02
10-2-2
Selection, installation, work failures specified
below and other failures
Note: Asterisk-marked items show concrete examples.
1. Model selection failures
•
A model not suitable for storage applications is selected.
* The cooling of products not reaching the target storage
temperatures.
•
Cooling overloading or underloading judged by our dealer.
* The frequency of stoppage is 6 or more times per hour or the
set cooling temperature is not attained.
2. Installation failure (installation and environmental problems)
•
The unit is not installed on a stable horizontal plane.
* The unit is not fixed securely.
•
The environmental conditions of the place of installation differ
from normal atmospheric conditions.
* Briny air environment, shore side, oil mist environment,
kitchen exhaust side, other corrosive gas and adhesive mist
environment.
•
The place of installation had poor ventilation and heat
dissipation.
* The machine took in exhausted air again.
3. Work failure
•
The interior of the piping was not vacuum dried sufficiently.
* The clogging of the thin areas of the piping caused by icing.
•
The interior of the piping was not sufficiently airtight.
* Leakage of refrigerant gas.
•
The interior of the piping was contaminated with foreign
substance.
* The clogging of the thin areas of the piping.
•
The unit was adversely affected by on-site modification work.
* The use of the unit beyond the operating temperature range as a
result of on-site modification.
•
An accident resulted from the improper handling of the unit
under installation work.
* The loosening or wobbling of the outer panel or broken or bent
damage to the piping.
4. Operational failure
•
Temperature settings for stored objects were wrong.
* The storage of vegetables at temperatures below 0°C.
•
The periodical maintenance of the unit was neglected.
* The clogging of the air heat exchanger, rust generation from
each part, gas leakage, and icing of the indoor unit (showcase
and unit cooler).
5. Others
•
Improvements recommended by our dealer in advance were
not accomplished.
* The simultaneous starting and stopping of a number of units.
•
Accidents were caused by natural disaster or fire.
* Damage to electrical parts caused by lightning.
•
There were other installation and operational problems beyond
common sense.
* The use of the unit without heat insulation work on the piping.
•
Work was conducted without keeping the following showcase
restrictions.
<Showcase restrictions>
· The installation of the thermostatic expansion valve and
liquid supply solenoid valve (both of which are for R410A) on
a showcase basis.
Thermal insulation of feeler tube of thermostatic expansion
valve must be thermal insulated.
· Install showcases on the same floor if the showcases are
connected to a single outdoor unit.
· Make sure that the outlet of piping used for the heat
exchanger is located downward (as shown on the following
figure).
11.
Inlet
(upper side)
Outlet
(lower side)
Heat exchanger
4PWEN74303-1C.book Page 7 Thursday, March 10, 2016 10:59 AM
