Repair Procedure
Fusible Link
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The machine is protected from overheating by a length of special wire. In the rare occurrence that the safety features of the machine fail and the roasting chamber overheats, the Fusible Link melts.
Begin by following these procedures:
Cooling tray
Front Cover
Bearing Plate and Drum
Remove Main Fan
Remove Rear Cover
Remove Top Cover
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All KN-8828P-2 and KN8828B-2 Hottop Coffee Roasters have this resistor between terminals T3 and T4 as shown here. If your roaster does not have this resistor, you must follow THIS PROCEDURE.
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Clip the tie wraps that hold the wire harness together.
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NOTE: Over time there has been some variation on the colors of some of the wires. The wires you will be dealing with may be red or may be white. So long as you chose the correct wires as identified by their connection points the color of the wires does not matter.
Examine the wires connected to terminals T5 and T6. One wire connects to the Heating Element. The other is part of the Fusible Link. Identify the one that is the part of the Fusible Link, and using a needle nose pliers, remove that wire. Be aware that it may be connected to EITHER Terminal T5 or at T6. Note that your board may look somewhat different from that shown here, but terminal numbering is the same for all roasters.
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Follow the directions to Remove the Motor. It is NOT necessary to completely remove the motor. Just the 4 screws holding the motor's mounting bracket to the machine indicated here. No wires need to be removed. Looking at the rear of the machine, move the motor off to the left to revel the fusible link. Do not allow the motor to hang by its wires. Take care to not scrape or damage the insulation of the wires. If you cannot safely support the motor either get assistance or remove it completely.
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Remove the other wire lead from the Fusible Link that connects to the Heating Element. The position of the wires may be reversed from the positions shown here. That is, the Fusible Link's wire you are removing in this step may be attached to the lower Heating Element's connection point.
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If you intend to replace this same Fusible Link, use a marker or pencil to make a mark above and below the clamp that holds the fusible link in place. Remove the screw holding the old Fusible Link and remove it along with its bracket. Carefully feed the longer lead up through the hole in the metal base taking care not to damage the insulation of the wire. Remove the old Fusible Link.
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To replace the Fusible Link, attach the bracket that was included with the repair kit to the new Fusible Link. Do not reuse the old bracket!
IMPORTANT: Note that the bracket attaches to the center, cylindrical, firm portion of the Fusible Link. Squeeze the link as shown here to find that portion of the link.
WARNING: If you fail to place the Fusible Link under the bracket in the correct location, it could result in damage to the Fusible Link and/or a fire hazard. The thick, hard portion of the link approximately at its midpoint. That is what the bracket must press against.
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Loosely attach the new Fusible Link to the roaster using the same hole. Use the new screw included with the kit. Be sure that the center portion of the fusible link, located under the bracket, sits flat against the back wall of the roasting chamber, and that no wires are trapped under the new link. Be sure to locate the Fusible Link and its wiring so that they cannot contact the heating element.
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Move the top end of the new Fusible link so that it is clear of the mounting hole for the Main Motor bracket. The wires in the link can be bent, but take care not to bend them close to the bracket, near the fusible portion itself (the stiff portion). When the link is clear of the hole as shown here, tighten the screw. Once again, make sure that the link is firmly up against the metal plate to which it is mounted.
WARNING!: The fusible link is part of the safety system designed into the Hottop coffee roasters. Its operation depends on sensing the heat of the roaster. It must be in firm contact with the metal of the roasting chamber as descried above. Failure to assure that this is done correctly can create a fire hazard!
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The Fusible Link has two wire leads. The short lead with the woven insulating cover attaches to the heating element. One wire coming from the Main Board is already attached to one connector of the heating element. The short Fusible Link wire with the woven sleeve insulation attaches to the other heating element connector. It does not matter which of the two heating element terminals you use for the Fusible link. The arrow here indicates that in this particular installation the Fusible Link is being attached to the upper Heating Element terminal.
IMPORTANT: Be sure to check that both spade connections on the heating element are tight. If loose, remove and use a small pair of pliers to carefully squeeze the female spade clips closed a bit and check for proper fit again. Use caution when pushing on the heating element's attachment points.
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Connect the Fusible Link to the Main Board. The two wires indicated here are:
1 - The lead from the Fusible Link
This is the longer lead from the new Fusible Link. Feed it through one of the holes in the metal dividing plate down to the Main Board. Take care to not scrape or damage the insulation of the wires.
2 - The lead from the Heating Element.
These two wires connect to terminals T5 and T6. It does not matter which lead is on which terminal, so long as these two leads connect, one each, to these two terminals.
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To complete the procedure:
Replace the Motor
Replace the tie wrap(s) on the wires leading to the main board
Replace Top Cover
Replace Rear Cover
Replace the Main Fan
Replace the Drum and the Bearing Plate
Replace Front Cover
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