Unit installation

Use and Maintenance Manual Air-cooled water chillers and Heat Pumps R-PAE/R-PAH/EAH Rev. 1 del 03/09

The motor pulley is of adjustable type. If to unscrew the fixing dies the regulation must be changed, it is necessary to

mark the original position with an indelible felt-tip pen and count the turns of the mobile part so that it is possible to

restablish exactly the original regulation once the operation is completed. Remove the protection paint from the shaft

and from the new motor key (use a brush, solvent and some cloths); clean the inside part of pulley, lubricate with oil

and install the pulley on the new motor making sure not to force the coupling. Once the pulley is entered into the shaft,

insert it completely by means of a hard rubber mallet and block it definitely with the appropriate dies. Mount the motor

and if needed restablish the original pulley regulation and tighten the belt (see par. 5.7.11). Reconnect the motor and

check the rotation by a short impulse given to the remote control switch after energizing it. If necessary, change the

electric connection (inverting the connection of two phase cables) after disconnecting the power supply. Close the

protection covers.

5.7.17 Replacement of compressors crankcase heaters

While making the check, the unit main switch must be open (“0” position) and locked. The padlock

key must be kept by the person in charge of the check.

The type of crankcase heater installed varies according to the type of compressor, if scroll or semi-hermetic; scroll

compressors need to be installed a tubular heater (see picture), while semi-hermetic compressors need a

cartridge heater (see drawing). The heater position may vary following the compressor type and model, anyway it

is always located on the underside of the compressor crankcase.

Picture 51 Picture 52

The tubular heater must be replaced by unscrewing the fixing screws (position indicated by the arrow in the picture)

so that it can be easily removed; mount the new heater in the same position of the replaced one and push it against

the compressor housing. The cartridge heater must be replaced by removing it from its location and installing in its

place the new heater. In order to improve the heat transmission, use conductive paste or oil.

The cartridge must not stick out from its location; the protruding part may overheat and stop

working.

5.7.18 Electrical cables check

The check is visual: the electrical cables must be not damaged or show abrasions, cuttings or overheating signs. In this

case, replace them immediately.

5.7.19 Contactors status check

This operation must be perfomed by an expert electrician able to dismantle and re-install the remote control switches

without damaging them. In case of blazed or blackened auxiliary switches or the whole remote control switch, make sure

the contactor interrupting power is adequate to the power it runs.