Bühler technologies EGK 2A Ex, Инструкция по установке и эксплуатации, Страница: 23 / 61

EGK 2A Ex
7.2.2 Cleaning the condenser (air heat exchanger)
Looking from the top, at the back of the sample gas cooler you will see the ribs of the condenser, protected by a cover. These
should be clean to ensure heat is removed adequately. They only need to be cleaned if large amounts of dust or deposits are vis-
ible. Carefully clean with compressed air. Never use harsh cleaning agents.
7.3 Parts replacement
NOTICE
In general, no parts of the sample gas cooler should be defective. We recommend only
having the Pt100, electronics, or starting capacitor replaced by the manufacturer's works
or trained customer service. You may perform the replacement according to the follow-
ing instructions. However, in this event Bühler Technologies GmbH is not responsible for
improper replacement.
7.3.1 Replacing the heat exchanger
For the heat exchanger model, please refer to the item number under chapter Introduction.
Heat exchangers only need to be replaced when clogged or damaged. If they are clogged, we recommend checking if using a fil-
ter will avoid future occurrences.
Please note the warnings under chapter Maintenance.
– De-energise and depressurise the system.
– Disconnect the gas connections and condensate drain.
– Pull the heat exchanger up and out.
– Clean the cooling nest (hole inside the cooler block).
– Apply silicone grease to the cooled outer surface of the new heat exchanger.
– Reinsert the heat exchanger into the cooling nest with a rotating movement.
– Reconnect according to chapter Electrical connections and potential equalisation.
7.3.2 Replacing the Pt100
Item no.: 45 90 999 6
– Observe the warnings in chapter Maintenance [> page 19].
– De-energise (supply and status outlet) and depressurise the system.
– Loosen the four screws in the corners of the front on the black terminal box.
– Carefully lift of cover: The control elements are attached to the to the electronics with cables.
– Turn the cover and put down on the cooler. Be careful not to tension the cables.
– Remove the conductors of the Pt100 from the terminals (top tow, far left, see drawing 47/170-10-3 in the appendix) and meas-
ure the resistance. Depending on its temperature it should be between approx. 102…110 Ohm. If the measurement differs sig-
nificantly, it is defective.
– Remove the cover for the pressure controls. To do so, remove the two screws, carefully pull the lower section forward, and
slide the cover upward. You will now see the two pressure controls.
– Loosen the screw connection of the Pt100 beneath the cooler block and carefully pull out the Pt100.
– Loosen the screw connection for the Pt100 cable at the terminal box and pull the cable out of the terminal box.
– Loosen the screw connection from the bracket below the pressure controls, carefully pull the cable out to the left.
– Insert the new Pt100 sensor through the screw connection using a little silicone grease – Do not yet tighten the screw connec-
tion.
– Feed the cable down through the screw connection, behind the pressure controls, and into the screw connection on the ter-
minal box. Do not forget the nuts and rubber rings.
– Connect the Pt100 (see drawing 47/170-10-3 in the appendix).
– Arrange the cable so it is without tension.
– Tighten the three cable glands at 2 Nm.
– Reattach the cover for the pressure controls and tighten the screw connection at 1.85 Nm.
21 Bühler Technologies GmbH BE450020 ◦ 01/2020