Table of Contents
Advertisement
INTRODUCTION
Notwithstanding that the units are equipped with extensive safety and protection features, the
utmost care and attention is needed when carrying out operations on the machine. Furthermore,
ear protection should be worn when working on or in the vicinity of the roof tops. Operations on the
cooling circuit or electrical equipment should be carried out by authorized personnel.
It is essential to follow non exhaustive recommendations hereunder:
Never work on a unit that is still energized. Wait 15 minutes before working on the machine after a
power outage (discharge of the capacitors).
Any manipulation (opening or closing) of a shut-off valve must be carried out by a qualified and
authorized engineer. These procedures must be carried out with the unit shut-down.
•
Never work on any of the electrical components, until the general power supply to the unit
has been cut. During any maintenance operations on the unit, lock the power supply circuit
in the open position ahead of the machine. If the work is interrupted, check the lock before
resuming the work.
•
WARNING: Even if the unit has been switched off, the power circuit remains energized, unless
the unit or circuit disconnect switch is open. Refer to the wiring diagram for further details.
•
In case of maintenance operations on fans (grills replacement ...) ensure that the power is
shut off to avoid automatic restart.
•
Before the opening of the refrigerant circuit, check the pressure with manometers or pressure
sensors, and purge the circuit.
•
Never leave a unit stopped with valves closed on the liquid line, refrigerant could be trapped
and the pressure would rise.
•
All installation parts must be maintained by the personnel in charge, in order to avoid
material deterioration and injuries to people. Faults and leaks must be repaired immediately.
The authorized technician must have the responsibility to repair the fault immediately. Each
time repairs have been carried out to the unit, the operation of the safety devices must be
re-checked.
•
Follow guidance and recommendations given in safety and machine standards such as EN378,
ISO5149, etc.
•
Do not use oxygen to purge lines or to pressurize a machine for any purpose. Oxygen gas
reacts violently with oil, grease, and other common substances.
•
Never exceed the specified maximum operating pressures.
•
Verify the allowable maximum high- and low-side test pressures by checking the instructions
in this manual and the pressures given on the unit name plate.
•
Do not use air for leak testing. Use only nidron or dry nitrogen.
•
Do not unweld or flame cut the refrigerant lines or any refrigerant circuit component until
all refrigerant (liquid and vapor) has been removed from roof top. Traces of vapor should be
displaced with dry air nitrogen. Refrigerant in contact with an open flame produces toxic
gases.
•
Do not siphon refrigerant
•
Avoid spilling liquid refrigerant on skin or splashing it into the eyes. Use safety goggles. Wash
any spills from the skin with soap and water. If liquid refrigerant enters the eyes, immediately
and abundantly flush the eyes with water and consult a doctor
e-MovAir-IOM-20.04-EN
6
www.lennoxemea.com
Advertisement
Table of Contents
