Service manual

Replacing the
Thermocouple
1 UNPLUG the kiln.
2 Remove the screws on the
sides of the switch box that
hold it to the kiln. Gently
lift the box away from the
kiln.
3 Remove the two screws secur
-
ing the thermocouple ceramic
block. Pull thermocouple from
its firebrick hole. Loosen the
screws holding the thermocou
-
ple to the ceramic block.
4 Slide the new thermocouple
into the thermocouple hole.
The thermocouple should
protrude into the firing
chamber 1” or more. To ad
-
just the thermocouple
length, change the gap be-
tween the thermocouple and
the ceramic block. Then se-
curely tighten the 4 screws
in the ceramic block.
5 Fasten the ceramic block to
the heat shield with the two
screws removed in step 3.
6 Digital Kilns: Remove the controller faceplate from
the front of the switch box. Manual Kilns: Remove
the pyrometer from the front of the switch box.
7 Digital Kilns: Remove the 2 thermocouple wires at
-
tached to the back of the controller. They are held in
place by button or lever type connectors. To remove
the wires, lift the levers (or press down on the con
-
nector buttons) and pull the wires out. Manual
Kilns: Remove the 2 thermocouple wires from the
back of the pyrometer.
8 Strip ½” of insulation from the ends of the new ther
-
mocouple wires. Be sure the wire ends are separated
where the insulation has been stripped. If bare ends
touch, the thermocouple will not work properly.
9 Attach the wires to the back of the controller or
pyrometer. One wire is yellow, the other red. Make
sure the wires connect to the correct terminals,
which are color coded. Reinstall the controller or
pyrometer to the switch box.
10 Position the thermocouple wires so they are away
from the hot sides of the kiln case and other electrical
wires. (Placing thermocouple wires next to or looped
around other wires could cause erratic controller
readings.)
11 Check that no wires touch the kiln case or element
connectors. Wires touching element connectors
or kiln case will burn. Reinstall switch box.
Replacing a Relay
Or Transformer
(Digital Kilns Only)
1 UNPLUG kiln.
2 Remove the screws on the sides of the switch box that
hold it to the kiln. Gently lift the box away from the
kiln.
3 The transformer and relay
are bolted to the inside of
the switch box. Hold the
new part next to the one you
are replacing, aligned in the
same direction. Remove and
transfer one wire at a time from the old part to the
new one. Make sure each connection is tight.
4 Replace push-on connectors
and wires damaged by heat.
If wire connectors do not fit
snugly on terminals, gently
squeeze the end of the ter
-
minal with pliers.
5 Remove the old part from
switch box. Install the replacement.
Note: If you are replacing the transformer, examine
the new one to make sure the primary is properly
wired for your kiln’s voltage. (See the kiln’s wiring
diagram.)
6 Check to see that wires are not touching kiln case or
the element connectors. Wires touching element
connectors or the kiln case will burn out. Move
switch box into place and reinstall switch box screws.
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