About Trouble-Shooting of the Bottle-Top Dispenser

As the most common instrument and equipment in the experiment, the bottle-top dispenser is suitable for general acids and bases, low concentrations of strong acids and alkalis, and salts. It enables accurate, highly repeatable dispensing operations without wasting reagents and meanwhile, it ensures the safety of the operator. However, some problems may arise during the operation. The following has summarized the most frequently FAQ and its solution. If these cannot solve your problem, welcome to contact the HAWACH after-sales team.

Bottle-top dispenser features
-Fast volume setting and precise scale design
-To make the operation convenient and comfortable, it installs smooth and precise piston sliding up and down
-Discharge tube safety helmet, which can avoid contact with reagents, even when wearing gloves, it can be easily installed or removed.
-Transparent pipette, suitable for reagent bottles of various sizes
-Strong chemical resistance
-Can be sterilized by high temperature
-Manual and electric bottle-top dispensers meet and cover the 0.1-99.9ml capacity range
-Convenient design ensures simple and economical cleaning and maintenance of the dispenser
-Made of optical glass, Al2O3, ETFE, PFA, FEP, PTFE, platinum-iridium alloy, PP (hard hat)

Forbidden solution
-Liquid reacting with ETFE, FEP, PEA, PTFE, Al2O3: sodium azide
-The liquid that corrodes optical glass: hydrofluoric acid (HF)
-Liquid of platinum-iridium alloy for catalytic decomposition (H2O2)
-Nicotinic acid, trifluoroacetic acid, tetrahydrofuran
-Explosive liquid: carbon disulfide
-Suspension: Carbon-containing solution
-Limiting solution: concentrated hydrochloric acid, nitric acid, chlorinated hydrocarbons, and fluorinated hydrocarbons, and liquids that can form deposits can cause piston stickiness or cause a blockage (such as crystalline or concentrated alkaline solutions).

ProblemPossible causeWhat you should do
Difficult to move the pistonFormation of crystals, dirtyStop dispensing immediately. Loosen the piston in a circular motion, but do not remove it. Please follow all cleaning instructions.
Not possible to fill1. Adjust the volume to the minimum
2. Stick filling valve
1.Set to required volume
2. Clean the filling valve. If necessary replace the valve with sealing washer
Dispensing liquid cannot be done1. Discharge tube cap pushed on
2. Weak connection or damage of the discharge tube
1. Capis removed
2. Push on the cap, hold the piston in place, and push the original manufacturer’s discharge tube on firmly. Replace a deformed or damaged discharge tube.
Air bubbles in the bottle-top dispenser1. Reagent drawn in too quicklywith high vapor pressure
2. Seal not inserted, knurled locking nuts not firmly connected
3. Air not expelled from the instrument
4. Filling tube not firmly connected or damaged
5. Valves dirty and installed loosely or damaged
1. Draw in reagent slowly.
2. Double check that seal is in place, and that the knurled locking nuts at the discharge tube are firmly seated and finger tight3. Priming the bottle-top dispenser.
4. Push the filling tube on firmly. If necessary cut off approx.
5. Cleaning process: take mounting tool to tighten valve. Valve and seal washer can be replaced, if necessary.
Too low dispensed volume1. Discharge tube not firmly connected or damaged
2. Filling tube not firmly connected or damaged
3. Valves not firmly installed or damaged
4. Sticking filling valve
1. Push the original manufacturer’s tube on firmly
2. Cleaning procedure: Push the filling tube firmly. If this does not suffice, cut off approx. 1 cm replace filling tube
3. Clean the bottle-top dispenser: Tighten the valves using the mounting tool, if necessary replace the valves and sealing washers
4. Clean or replace discharge tube, if necessary.