KEOFITT W9 USER MANUAL V.4 PAGE 37
13. MAINTENANCE
13.1 Maintainance
All membranes must be inspected between batches.
The EPDM and Silicone membranes should be replaced at every batch change or at least every 2-3
months. PTFE and FFKM membranes should be replaced every 12 months. In the event of intensive
sterilisation and cleaning it may be necessary to replace it more frequently. The appropriate replacement
frequency should be determined by the user by starting with short intervals and continuously extend the
time in use until one reaches the limit of the membrane’s durability. Based on the desired safety margin
the user then decides on the replacement interval to adapt.
For valve heads with Micro Port, approx. 5-10 samples may be drawn o per membrane at 5-2 bar(g)
respectively (more piercings are acceptable at lower pressure). See chapter 3.5 Membranes for more
information.
The rubber plug must be replaced at least once every six months. In each individual case a standard
operating procedure including maintance intervals should be endorsed based on experience. For
disassembly of valve body and valve head, see instructions in chapter 13.3.
13.2 Spare parts list
1. Valve body
2. Membrane Silicone (grey), Membrane EPDM (black), Membranes PTFE and FFKM (white)
3. Lower stem (slightly dierent shape for PTFE membrane)
4. Spring (except type B)
5. Steel bushing