ELGA PURELAB UHQ II & PS Service
Manual
PURELAB UHQ II & PS Service issue 2 03/07
33
Appendix A. UHQ SANITIZATION PROCEDURE.
The following sanitization procedure, using CT3 chlorine tablets or hydrogen
peroxide (H
2
O
2)
, may be found beneficial for PURELAB UHQ users who require to
maintain the lowest TOC or bacterial levels. The frequency at which sanitizations
should be carried will depend on many factors and cannot be predicted. As well as
prior to critical applications, the sanitization would be of obvious benefit after a period
of prolonged storage or non-use of the PURELAB UHQ.
The procedure can be carried out at any time, simply by fitting the two vertical by-
pass tubes supplied with each PURELAB UHQ when new. The procedure involves
the re-circulation of chlorine or H
2
O
2
solution and four subsequent rinses using fresh
RO permeate water. The procedure can be accelerated by using an externally
prepared source of deionised water for the rinses which can be poured in through the
top cap on the reservoir.
CAUTION! Care must always be taken when filling the reservoir through
the top cap to ensure it is not overfilled. Over filling will result
in water flowing down the vent tube, causing subsequent
damage to the UHQ4 composite vent filter.
The sanitization procedure is as follows:
1. Disconnect the silicon tubing from the UHQ1 and UHQ2 cartridges, both of which
are incompatible with Chlorine or H
2
O
2
(see fig A1 on next page). The UHQ7 Ultra
Microfiltration cartridge is compatible and can be left in place during re-circulation.
2. Fit the two rigid vertical by-pass tubes in place of the UHQ1 and UHQ2 cartridges
and push-fit the flexible interconnecting tubes.
3. Check that the PURELAB UHQ is connected to the mains power and the POWER
light is illuminated.
4. If the PURELAB UHQ has not been used for prolonged periods, empty the
reservoir as follows:
Open the white tap to allow the water to pass to drain and push the PROCESS
control button on the fascia panel. Water will be pumped from the reservoir to drain.
5. Fill the reservoir with fresh RO permeate, by pushing the REFILL button or,
manually, using good quality deionised or distilled water through the top cap. The
PURELAB UHQ II reservoir takes approximately 1 hour to fill automatically.
7. Add either 1 x CT3 tablet or 140ml of 30% w/v H
2
O
2
(100 volumes) and manually
mix thoroughly.
Note: The CT3 tablet is effervescent and will quickly dissolve into the tank contents
without need for manual stirring. H
2
O
2
will require thorough mixing before proceeding
with the recirculation.
7. Press the PROCESS button (the PROCESS light illuminates) and allow the unit to
re-circulate for 20 minutes. Ignore the illuminated READY light. During this time,
periodically (1 minute approximately every 10 minutes), dispense the sanitizing
solution from the Dispense Pen back into the top of the reservoir. This allows the pen
tip to be fully disinfected.
8. After 20 minutes drain the reservoir by connecting the tube to the white tap,
described previously in Step 4.
9. Refill the reservoir as previously described in Step 5 (automatically, or
manually to save time).
10. Push the PROCESS button and re-circulate for 5 minutes
11. Again, drain the reservoir as previously described in Step 4, flush the pen tip by
periodically dispensing water back to the reservoir during each rinse.
!
