BUTTON TRAP: Hold the button trap basket up to the light to check that the perforations are not blocked
It is the operator’s responsibility to constantly monitor the drycleaning machine, to ensure that at all times the machine operates efficiently. We would suggest that in a busy unit, the cleaning cycle on a full ‘normal’ process load is carefully checked on a weekly basis. This should expose serious developing issues such as slipping belts, programme errors/imbalances, incorrect dip levels, poor solvent flow through the pump and filter, and distillation rates. A noisy pump often indicates cavitation (check that the holes in the button trap mesh are not blocked) or debris obstructing the impeller.
Water separator
AIR FILTER: Regularly check the air filter screens for damage and worn/poorly fitting seals.
For the separator to operate efficiently, and to avoid the risk of solvent being carried over with the wastewater, the separator needs to be drained and cleaned as soon as debris starts to collect at the solvent/water interface. While some separators may need to be cleaned on a weekly basis, others may remain in a clean condition for much longer periods. Slightly cloudy solvent in the separator is normal in the next load after still-cleaning, but it should rapidly clear. At any other time, ongoing cloudiness in the separator or distilled tank should be investigated immediately because it indicates the presence of moisture (or even water droplets) in the solvent. This puts garments at high risk of greying and shrinkage. A perforated still steam-heater, still condenser or air-heater are the most likely causes of the problem.
WATER SEPERATOR:The water separator needs to be drained and cleaned when dirt/sludge begins to accumulate at the solvent/water interface
On older machines, a blue or greenish discolouration appearing in the separator water indicates that copper corrosion is starting to occur on the still condenser coil. While this does not normally pose an immediate problem the still condenser needs to be checked out by the engineer.
Filter pressure
On many of today’s machines, both the filter pressure gauge and the filtered solvent sight glass can be found in the back of the machine and not in the front panel (where they really should be located for easy visual access). In our experience, probably due to their location, they are rarely if ever checked by the operator and all too often the operator does not understand the significance of high filter
SHOCK FACTOR: It is not difficult to imagine the standard of cleaning this disc filter produced
pressure and (even more importantly) low filter pressure, together with poor/ intermittent flow through the filtered solvent sight-glass during filtration. Very low or fluctuating filter pressure (often seen together with bubbles in the filtered solvent sight-glass) and varying noise levels coming from the pump, are serious problems which demand the operator’s immediate attention. They are frequently associated with a blocked button trap, or solvent flow that is insufficient to allow the automatic programmes to maintain the correct dip levels and distillation ratio. Low and fluctuating pressure can also be the result of items such as safety pins or small coins providing a foundation for lint and debris to accumulate and obstruct the pump. This reduces to a varying degree the volume of solvent delivered by the pump and consequently the filter pressure. The first obvious sign of a developing pump problem is usually a variation in the sound of the pump, which in some cases can become very noisy. A good operator will pick this up immediately and investigate by checking the flowrate during the filling of the cage. It is also important to examine the button trap basket for damage and to ascertain whether or not it is seating correctly in the button trap and preventing debris bypassing the basket or escaping through a damaged area. Filter pressure and pump problems are frequently responsible for: Risk of greying to medium, light and particularly white items due to incomplete removal of particulates from the filtered solvent.
High risk of unpleasant odours in cleaned items due to insufficient distillation.
Risk of physical damage to lightweight/ delicate items from excessive mechanical action caused by low dip levels. Finally, while the issues that we have discussed are not exhaustive, we hope they will provide a good basis for investigating and resolving some common machine operating mistakes, helping our readers to understand how a simple fault like not having enough solvent in the machine can seriously impact on the automatic operation of the machine, putting customers’ clothes at risk and leading to legitimate complaints and claims for compensation.
If you have problems you would like the authors to examine, please send with a good quality, high resolution (300dpi/1MB at least) pic of the item to
kathy.bowry@
laundryandcleaningnews.com
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