M&C TechGroup EC-30_FD Operator's manual - Manual (Page 23)

23
Gas sampling and gas conditioning technology 3-4.20-ME
16.2 REPLACING THE HEAT EXCHANGERS
Removal of the heat exchangers may be necessary to carry out maintenance or repair work. It is
possible to replace the heat exchanger  (pre-cooling stage) without switching off the entire cooler.
This does not apply to the heat exchangers of the low-temperature stages 
and . Icing-up at
operating temperatures of -30

C will make it impossible to dismantle the unit. It will take approximately
two hours to defrost after switching off the cooler. We recommend the following procedures for
replacement of the heat exchangers in the following order:

Release the GL coupling rings by turning them to the left at the upper gas connections and
lower condensate connections to the glass heat exchangers;

Pull the heat exchangers upwards with rotation out of the cooling block;

Dry and clean the push-in opening in the aluminium cooling block with a cloth;

Smear thermal conductivity paste (part no. 90K0115) on the heat exchangers with a thin and
equal layer over the whole surface to ensure good conduction of heat. It is best to shut the
condensate outlet of the heat exchangers with adhesive tape to prevent any of the thermal
conductivity paste from getting into the heat exchanger;

Lightly push the heat exchangers back into the opening of the cooling block and press to the
upper limit stop;

Remove the adhesive tape and any surplus thermal conductivity paste;

Reconnect the hoses as shown in the flow diagram (fig. 4).
N O T E !
Do not mix up the hose connections; the outlet hose for the low temperature
stage is marked in red!

Check the PTFE/Silicon locking rings for damage. In assembly, the locking rings must have the
PTFE side facing the medium, otherwise the required degree of sealing cannot be guaranteed!

Screw on the red GL coupling rings hand tight by turning them to the right.