Lennox INNOV DM R Series Application Manual page 53

9 Maintenance
The only operations to be performed by the user are to switch the unit on and off. All other operations are to be
considered maintenance work and must thus be carried out by qualified personnel trained to do their job in
accordance with current laws and regulations.
9.1 Warnings
All the operations described in this chapter MUST ALWAYS BE PERFORMED BY QUALIFIED
PERSONNEL ONLY.
Before carrying out any work on the unit or accessing internal parts, make sure you have
disconnected it from the mains electricity supply.
The upper part and the outlet pipe of the compressor reach high temperatures. Be especially
careful when working in the surrounding area with the panels off.
Be especially careful when working in proximity to finned coils since the 0.11 mm-thick aluminum
fins can cause superficial injuries due to cuts.
After completing maintenance jobs, always replace the panels enclosing the units and secure
them with the fastening screws provided.
9.2 Generalities
To guarantee a constantly satisfactory performance over time, it is advisable to carry out routine maintenance
and checks as described below. The indications below are related to standard tear and wear.
tab. 7 Routine maintenance
Operation
Check the efficiency of all the control and safety devices.
Check the terminals on the electric control board and compressor terminal boards to ensure that
they are securely tightened. The movable and fixed contacts of the circuit breakers must be
periodically cleaned and replaced whenever they show signs of deterioration.
Check the refrigerant level by means of the liquid level indicator.
Check the efficiency of the differential air pressure switch and dirty filter differential pressure switch
(option).
Check the condition of the air filter and replace it if necessary.
Check the humidity indicator (green = dry, yellow = humid) on the liquid level indicator; if the
indicator is not green as shown on the indicator sticker (see pag.20).
Check the refrigerant charge (see page 20).
INNOV@ ECFAN DHR -AGU-0912-E
Frequency
Once a year
Once a year
Every 6 months
Every 6 months
Every 6 months
Every 6 months
Every 6 months
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