Endress+Hauser TOC Analyzer CA79, Operating Instructions Manual

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Diagnostics and troubleshooting TOC Analyzer CA79
42 Hauser
10 Diagnostics and troubleshooting
10.1 Replacing the hose system
To ensure the hose fittings are seated correctly, it is advisable to cut the hoses to
length with a special hose cutter to ensure a straight cut surface and to avoid the
deformation of the hose ends.
The procedure for replacing a hose system is described below. The hoses used are made
from FEP and are therefore unaffected by aqueous media in the pure and ultrapure water
range and do not appreciably contribute to the TOC in the system.
These hose systems may need to be replaced if a large amount of contamination has
entered the system or the system has been used with unsuitable media. In addition, parts
of the hose system (hosing subsections) must be replaced if leaks have occurred in the
system. Such leaks can be caused if an unsuitable process pressure is applied, for example.
UNF fittings, which are also used in chromatography, are used as the fittings here. These
fittings consist of a suitable ferrule and a suitable screw connector (referred to as a socket
below) made of PEEK.
Ferrules undergo permanent mechanical deformation during installation and must be
replaced with each new hosing. The socket can be reused if it is not damaged.
The following materials are needed to replace a hosing subsection:
• 2 x ferrules (suitable for 1/8" hose, yellow color code)
• 2 x ¼-28 UNF fittings
• 1 x 1/8" FEP hose of adequate length
• Hose cutter for capillaries
1 2 3
A0047336
 36 Hosing subsection
1 Ferrule
2 Screw connection (socket)
3 Hose
1. Turn the fittings on the hosing subsection counterclockwise to loosen them.
2. Remove the section of hose from the housing and determine the total length of the
hose.
 The length is measured from ferrule to ferrule.
3. After determining the correct length, cut the new hose to length and cut both ends
straight at right angles using the hose cutter.
4. Fit the first ferrule on one end of the hose and slide the socket over the hose.
A0047337
 37 Fitting the ferrule and hose in place