Troubleshooting; Sample Collection; Diluting The Sample - palintest Pooltest 25 Manual

5

TROUBLESHOOTING

Sample Collection

Take pool water samples from below the water surface. Collect in a clean
plastic bottle and fill to the neck so as to avoid unnecessary airspace.
The free chlorine, bromine or ozone levels may drop during sample storage.
Other parameters such as pH and alkalinity can also change. Samples
should therefore be tested as soon as possible after sample collection.

Diluting the Sample

When the test result is outside the concentration range of the test, the
photometer will display the > > symbol. In such cases, it is necessary to
dilute the pool water and repeat the test. If the result is close to the top of
the scale (eg chlorine above 4 mg/l on Chlorine-Free/5 or Chlorine-Total/5
range, calcium hardness above 300 mg/l or cyanuric acid above 150 mg/l)
and a more accurate result is required, a dilution may be used to increase
the sensitivity of the test :-
1 Take a Dilution Tube (PT 512) and fill to the x2 mark with pool water.
Make-up to the 'Deionised Water' mark with deionised water. Replace
the tube cap and mix.
2 Carry out the test on the diluted sample in a 10 ml test tube as per the
normal test instructions.
3 Take the photometer reading in the normal manner.
4 Multiply the test result display be x2 to find the concentration in the
original pool water sample.
Samples may be diluted to a greater extent if necessary. Use the dilution
factor appropriate to the dilution used.
Note: it is not possible to dilute samples in the pH test, or when
working in transmittance.
It is very important to specify Palintest Photometer Grade tablets
when ordering replacement reagents for this instrument. Using an
alternative grade of tablet may lead to a turbid sample which in turn
leads to inaccurate results.
36