Carbolite CFM Series - Manual (Page 11)

CFM
MF10 - 3.08
11
5.7 Element Fitting and Replacement - 1400°C models
Replacements: read the section on element aging (0). If at any time the power limit has been
increased, measure the new element resistances and recalculate the limit.
Disconnect the furnace from the electrical supply.
Remove the furnace end panels to gain access to the element connections.
The elements are expensive and fragile, and can be damaged by contamination: handle them with
care and keep them clean.
Replacements only: make a note of the actual braid and cable connections to the elements.
Disconnect the clips with the special tool provided (or with finger pressure, depending on the type
of clips supplied), lift off the braids and carefully withdraw each element. See fig. 5.
Carefully insert the new elements into the furnace.
Attach the connection braids according to the note made above or to the appropriate diagram,
fig. 6. Use the special tool (or finger pressure) to fit the clips. Take care that adjacent clips do not
touch each other.
Replace the furnace end guards and connect the furnace to the supply.
If aged elements have been replaced, reset the furnace power limit.
CFM 14/4: this model has 6 elements in series on 220-240V. On 110-120V these are connected as
two sets of 3 elements in series, in which case the L and N connections are at opposite ends of the
furnace.
5.8 Fuse Replacement
Fuses are marked on the circuit diagram (section 7.0) with type codes, e.g. F1, F2. A list of the
correct fuses is given in section 7.5. Depending on model and voltage, the different fuse types may
or may not be fitted.
If any fuse has failed, it is advisable for an electrician to check the internal circuits.
Replace any failed fuses with the correct type. For safety reasons do not fit larger capacity fuses
without first consulting Carbolite.
The fuses are near the cable entry point, and access is by removal of a panel.