Volume Setting and Autoclaving of Bottle-Top Dispenser

1.Volume setting
– under the discharge tube opening, hold a suitable collecting container
– slowly and evenly pull the piston up to the stop to suck the reagent into the glass bottle.
– gently and evenly push down the piston to distribute the reagent into the container.
Please pay attention to the piston in the down position after use.

2.Drying tube connection(optional)
PTFE tape should be used for the thread of the bottle and/or thread adapter.

3.Cleaning/replacing the filling valve
a. To clean bottle-top dispenser, read the cleaning instructions first and follow it.
b. Remove and unscrew the filling tube.
c. Take the sealing washer to remove the valve. Make sure the sealing washer does not remain in the valve block.
d. Take cleaning solution to rinse the filling valve, and clean with soft brush. If valve ball is stuck slightly press with a plastic pipette tip to loosen it.
e. First, screw the cleaned/new filling valve together with its sealing washer into the valve block by hand and then tighten it firmly using the mounting tool.

4. Cleaning/replacing the discharge valve
a. Follow all cleaning instructions.
b. Unscrew the discharge tube.
c. Remove the valve locking ring.
d. Take the mounting tool to unscrew the discharge valve. Take the sealing washer to remove the valve. Make sure the sealing washer does not remain in the valve block.
e. Take cleaning solution to rinse the discharge valve, and clean with a soft brush. If the valve ball is stuck slightly press with a plastic pipette tip to loosen it.
f. First, screw the cleaned/new discharge valve together with its sealing washer into the valve block by hand and then tighten it firmly using the mounting tool.
g. Slide on the valve locking ring making sure the two prongs properly align with the notches.

5.Autoclaving
Preparation before first autoclaving
– Unscrew filling valve and discharge valve.
– Replace built-in PTFE-rings with the supplied elastic O-rings made of FKM.
– First, screw in the filling valve by hand and then discharge valve and tighten them firmly using the mounting tool.

Observe the reduced chemical resistance of FKM!
1. Clean the instrument before sterilization.
2. Remove the discharge tube with removed closure cap, filling tube, and drying tube, and put all parts on a towel. Avoid contact with hot metal surfaces.
3. Autoclave all parts.

Note
Allow to cool down in the closed autoclave to the avoided formation through too rapid cooling. Inspect all parts for deformities or damage, After every autoclaving. Replace them, if necessary. Do not re-assemble the bottle-top dispenser until it has cooled down to room temperature (cooling time approx. 2 hours). The mounting tool can be autoclaved at 121℃.

6.Volume check
The accuracy and coefficient of variation of the instrument are determined gravimetrically as follows:
– Set to the nominal volume.
– Dispense distilled H2O.
– The dispensed quantity is weighed on an analytical balance.
– Calculate the distribution considering the temperature
– Perform at least 10 dispensing and weighing operations.
– Calculate the accuracy (A%) and the coefficient of variation (CV%) by means of the formula used in statistical quality control. Read through the operating manual of the balance manufacturer and the corresponding standards. If there is any doubt, contact the manufacturer.

Hawach provides both manual and automatic bottle-top dispensers with different specifications to meet customer requirements. Welcome to visit https://www.hawach.com/ to learn more.