Agilent Technologies Agilent 7890 Series, Maintenance Manual

Page: 123 / 354

Maintaining the COC Inlet
7
Maintaining Your GC 123
To Replace the Fused Silica Needle in a Syringe for the COC Inlet
1 Gather the following:
• New fused silica syringe needle (See “Consumables and
Parts for the COC Inlet” on page 102.)
• Solvent
2
Loosen the retaining nut and remove the old needle.
3
Hold the syringe vertically and insert the new fused silica
needle so it is visible inside the syringe barrel. If the
needle cannot be inserted into the syringe barrel, the
PTFE ferrule may be blocked. You may need to replace
the ferrule.
4
Push the plunger down until it bottoms. The needle will
be flush with the plunger end.
5 Finger- tighten the retaining nut. Pull the needle gently to
be sure the PTFE ferrule has formed a tight seal with the
needle. Tighten the retaining nut further, if necessary.
N O T E
The fused silica needle and syringe are only used with the cooling tower
and duckbill septum for manual, on-column injections onto 200-µm
columns.
WA R N I N G
Wear safety glasses to protect your eyes from flying particles
while handling, cutting, or installing glass or fused silica capillary
columns. Use care in handling these columns to prevent puncture
wounds.
Fused silica needle
PTFE ferrule