Carbolite VMF Series - Manual (Page 11)

AAF, GSM, VMF
MF06 3.32
11
5.8 VMF 10/6 Element Replacement
See section 5.2 - wearing a face mask is recommended.
The heating elements are vacuum formed modules; they are fragile, so spare elements are supplied
complete in an insulation box to avoid damage.
Disconnect the furnace, remove the back panel, make a plan of all the internal connections to the
back of the heating chamber and disconnect. Remove the thermocouple(s) and support tube(s).
Using a socket spanner undo the four bolts that fasten the insulation box. These are located under
the insulation box in the two cross supports.
Remove the insulation box by carefully sliding it out through the back of the furnace case.
Carefully slide in the new insulation box, and fasten the four bolts. DO NOT support the element
by putting your hand inside the chamber – the element is fragile.
As necessary, shorten the element tails by clipping to length. Remake all the thermocouple and
element connections according to the individual plan.
Refit the back panel and run the furnace for 30 minutes at 800°C without interruption to ensure
complete burn-off of any organic binders, Some smoke may be observed during this process,
which should be carried out in a well ventilated area.
Check that the furnace is controlling properly to rule out the possibility that the previous element
failed because of a fault elsewhere in the control circuit.
5.9 Door Plug Replacement
Lift the furnace door to the open position and remove the door cover from the plug carrier
assembly.
Remove the old door plug by sliding it upwards out of its carrier.
Slide the new plug into the carrier assembly making sure that the plug is the correct way up.
Refit the door cover.
When first heating the furnace after a replacement, ensure that the ventilation is good: emission of
some fumes may be expected.
5.10 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 8.1. 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 the back panel.