7.0 Repairs and Replacements
7.4
Solid-state Relay Replacement
Disconnect the product from the power supply and remove the
appropriate cover as given above.
1. Make a note of the wire connections to the solid state relay, then disconnect them.
2. Remove the solid state relay from the base panel or aluminium plate.
3. Replace and reconnect the solid state relay ensuring that the bottom of it has good
thermal contact with the base panel or aluminium plate.
4. Replace the access panel.
7.5
Thermocouple Replacement
Disconnect the product from the power supply. Remove the appropriate panel
to gain access to the thermocouple connections. Make a note of the
thermocouple connections.
Thermocouple cable colour codings are:
Thermocouple Leg
Colour
positive (type K)
green
negative
white
1. Disconnect the thermocouple to be replaced from its terminal block and withdraw
it.
2. Re-assemble the new thermocouple, observing the colour coding.
3. Refit the element access panel.
7.6
Element Replacement
See section 7.2 - wearing a face mask is required.
The mineral insulated type of element consists of a resistance wire which is centered in
a metal tube by a compressed powder. Such elements may be bent into "U" or other
shapes without losing the electrical insulation.
Disconnect the furnace from the electrical supply. Remove the furnace back panel.
Carefully note how the elements are connected and remove the electrical leads from
them.
Unscrew the gland caps on the faulty element and carefully prise open the split
compression collars, which should be retained for fitting to the new element.
Remove the chimney, open the furnace door and slide out the chamber liner. Withdraw
the element through the front of the furnace.
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Summary of Contents for CARBOLITE GERO HRF 7/45
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