Description
Always make sure that the machine is disconnected from the power supply before opening any covers or attempting to check or replace any parts.
These instructions apply to 700 and 8000 Dryers.
CHANGING A THERMOCOUPLE ELEMENT.
1.To access the thermocouple element remove the top cover of the machine, remove any insulation trays.
2.The power supply cables to the elements have to be disconnected from the ends of the buss-bar conductors. Remember which ones go to each connection.
3.The temperature sensor cable should be disconnected at the small ceramic connector block on the heating element side of the ceramic block. At this point make a note or mark the on the terminal that the positive (red or brown) wire connects to. In some of the older dryers the temperature sensor cable was green (positive +) and white (negative -). The positive thermocouple wire from the heating element is marked with a spot, which may be red, green or black and this connects to the red or brown line in the thermocouple cable that goes to the temperature controller.
4. The galvanised heating element cover can be unscrewed and removed.
5.The old temperature sensor/heating element can simply be unclipped and the new one inserted and clipped in in the same way as the original element was. The temperature sensor/heating element is the one with 4 wires.
If you get the thermocouple lines the wrong way round the dryer will not work correctly. Often the dryer will begin to heat up and then cool down again or the temperature will appear to drop.
Make sure all connections are firmly made when you put the machine back together. A loose connection will quickly burn, spark and break.
NB. The new temperature sensor may show a slightly different temperature to the old one. Test that the temperature is what you require before processing a large amount of shirts. THIS MAY BE FROM A DIFFERENT MANUFACTURER YOU MAY POSSIBLY HAVE TO RUN YOUR DRYER TO 40 to 60 DEGREES HIGHER ON THE TEMPERATURE CONTROLLER TO ACHIEVE THE SAME TEMPERATURE AS BEFORE
CHECKING A HEATING ELEMENT.
A heating element should last at least 12 years. 99.99% of the time heating elements either work or they do not. There is no situation where they work but do not reach the desired temperature. This is caused by a fault in either the temperature sensor, controller or relay. There are 2 ways to check that the elements are working.
1.You can use an infra red temperature gun to physically check by directing the gun on the lower face of the element. Do not touch the elements with your hand you may burn yourself.
2. You can unscrew one connection from an element and check the resistance of the element using a multi-meter. Various elements that we use have resistances between
Typically 72 and 132 Ohms.
