Repair And Replacement - Chromalox CXH-A/B-03S Installation, Operation And Maintenance Instructions

8. Repair and Replacement

Replacing the Heat Exchanger
Depending on model, heat exchanger weighs between 50 -
100lbs (approx. 25-50kg) and must be properly supported
from bottom during removal.
1. Remove front case panel by removing 5 screws located
on perimeter of case.
2. Remove bottom case panel by removing 4 screws at-
taching it to panel wrapper (2 screws located on back
and 1 on each side).
3. Remove heat exchanger terminal box cover by removing
4 screws attaching it to panel wrapper.
4. Remove main control enclosure cover bolts.
5. Inside main control enclosure, disconnect wires entering
from bottom (heating element lead wires and cutout lead
wires).
6. To detach conduit union, secure outer sleeve and turn in-
ner holding the nut closest to the enclosure. Once the red
nut is loose, it can be slid over the conduit and rested on
the heater terminal housing. To expose inner sleeve, heat
exchanger may need to be lowered slightly away from
main control enclosure. See step 7.
7. Support heat exchanger from bottom, then remove 3
bolts that secure heat exchanger to panel wrapper.
8. Lower heat exchanger away from case, while guiding
wires out of main control enclosure. It is critical that the
conduit seal stay in place and is not disturbed.
9. To install new heat exchanger core, reverse step order.
Replacement heat exchanger core will include conduit
riser and epoxy seal. The seal must remain in tact to
maintain hazardous location listing.
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