Carbolite GVC Series - Manual (Page 11)

G range
MF48 -1.18
11
5.0 R EPAIRS & R EPLACEMENTS
5.1 Safety Warning – Disconnection from Supply
Always ensure that the furnace is disconnected from the supply before repair work is
carried out.
5.2 Safety Warning - Refractory Fibrous Insulation
Insulation made from High Temperature Insulation Wool
Refractory Ceramic Fibre , (better described as Alumino Silicate Wool) (ASW)
This product contains alumino silicate wool products in its thermal insulation.
These materials may be in the form of blanket or felt, formed board or shapes, mineral wool slab
or loose fill wool.
Whilst there is no evidence of any long term health hazards, we strongly recommend that safety
precautions are taken whenever the materials are handled.
Exposure to fibrous dust may cause respiratory disease.
When handling the material always use an approved respiratory protection equipment
(RPE-i.e. FFP3), eye protection, gloves and long sleeved clothing.
Avoid breaking up waste material. Dispose of waste in sealed containers.
After handling rinse exposed skin with water before washing gently with soap (not
detergent). Wash work clothing separately.
Before commencing any major repairs we recommend reference to the European Association
representing the High Temperature Insulation Wool industry (www.ecfia.eu)
We can provide further information on request. Alternatively our service division can quote for
any repairs to be carried out at your premises or ours.
5.3 Temperature Controller Replacement
301. This controller is fitted to the back of the control panel; in many models this can be separated
from the base by removal of two screws.
Before handling the controller: wear an anti-static wrist strap or otherwise avoid any possibility
of damage to the unit by static electricity.
Refer to the detailed instructions supplied with the replacement controller.
2132, 3216, 3508, etc. Ease apart the two lugs at the side; grip the instrument and withdraw it from
its sleeve; push in the replacement.
5.4 Solid-state Relay Replacement
Disconnect the furnace from the supply and remove the back panel from the base or control box..
Make a note of how the wires are connected to the solid state relay, and disconnect them.
Remove the solid state relay (SSR) from the base panel or aluminium plate.
Replace and reconnect the solid state relay ensuring that the heat-conducting thermal pad is
sandwiched between the relay and the base panel or aluminium plate. Alternatively a thin layer of
white, heat-conducting silicon paste may be applied between the new relay and the plate.
Replace the removed panel.
Users of older furnaces may be familiar with the circular “MOV” attached to the SSR. This is no
longer required with current SSRs.
5.5 Thermocouple Replacement
The coverings and guards which must be removed to gain access to the thermocouple depend on
the model, and possibly other options and fittings. For the horizontal models it will be necessary to