Candidate Support Pack - Scottish Qualifications Authority

If a bag gets stuck, and is not quickly un-jammed, the CTW will assume a load has been
discharged into the loading hopper and continue operating.
Every jammed bag represents a lost load of work and should be avoided.
Blockages
A further risk of the overhead rail bags jamming arises when two loads of work are
discharged into the same compartment, which produces a gross overload and increases
the risk of a blockage.
Sometimes the two loads in the pre-wash stage will successfully transfer through to the
main wash stage because of the higher water level which can help to float the larger
load over into the next compartment. However, once a double load reaches the main
wash stage where the water level is significantly lower (to give better mechanical action)
there may be insufficient water to help with the transfer — and so the double load gets
blocked and no further work can be done until the blockage has been removed.
Blockages can also occur if the water levels in the washing machine are incorrectly set.
If the water level is too high it is possible for larger items to 'float' over the compartment
divider and then, with the regular oscillation of the CTW action, become entangled and
cause a blockage.
Similarly, if the water levels are too low, there will be insufficient water to lubricate and
help the load transfer to the next compartment — and it stays where it is until the next
load joins it.
The key problem with blockages, especially when they occur in the main wash stage, is
that you are unable to detect them until either work stops coming out from the discharge
end or the loading chute becomes blocked because there is no room left inside for the
next load to enter the machine.
In both situations there can be as many as six loads of work now entangled inside of the
machine.
There are very special actions required when attempting to unblock a CTW and
this should NEVER be attempted without correct guidance and supervision.
As soon as a blockage is identified STOP the machine and immediately call the
engineer and your supervisor.
Tumbler efficiency
In the event that the tumblers connected to the CTW are not performing effectively, the
effect on both the CTW and the finishing departments is significant.
There are a variety of reasons why tumblers may lose efficiency, ranging from low
steam pressure to blocked air-intakes on heater batteries, blocked filters and lint
screens, poorly fitting door seals, fans not functioning correctly and so on. The specific
problems — and how to check and resolve them on tumble dryers — is the subject of a
separate training module.
However, reduced or poor tumbler efficiency will have a major negative impact on both
the production output from the CTW as it will go into a holding mode whilst waiting for a
tumbler to be discharged.
GC8N 22 — Laundry Operations Level 2 5.71