Follow these instructions to replace the
PR53SD wash nozzle assembly.
WARNING Process refractometers may
be installed in processes that have hot, cold, caustic, or otherwise hazardous liquids. When
installing or removing the refractometer from the process, use personal protective equipment
(PPE) adequate for the process medium and according to the requirements of the installation
site.
WARNING If you have a wash system
in place or are planning to install a wash system, make sure to familiarize yourself with
safety regulations related to hot steam and water. For more details, see the related wash
system user guide.
WARNING Surfaces on the equipment are hot. Use suitable personal protective
equipment (PPE).
PR53SD wash nozzle (Vaisala item
DRW258211SP)
46 mm wrench
9/16 in wrench
PR53SD wash nozzle assemblyPR53SD wash nozzle parts
1
Steam wash nozzle fitting
2
Shut-off steam valve
3
Safety pin
4
Wash nozzle nut
5
Wash isolation valve
Familiarize yourself with the safety instructions of the installation site.
Make sure the process line is depressurized and empty.
Close the shut-off steam valve (2).
Disconnect the steam hose using a 9/16 in wrench.
Remove the safety pin (3).
Loosen the wash nozzle nut (4) 2 turns using a 46-mm wrench. Do not fully loosen the
nut.
Pull the steam wash nozzle out until it stops.
Close the wash isolation valve (5).
Loosen the wash nozzle nut (4) fully using a 46-mm wrench.
Pull out the steam wash nozzle.
Push the new steam wash nozzle into the wash isolation valve (5).
Tighten the wash nozzle nut (4) a few turns using a 46-mm wrench. Do not tighten
fully.
Open the wash isolation valve (5).
Push the steam wash nozzle fully into the process.
Reinstall the safety pin (3).
Tighten the wash nozzle nut (4) with a 46-mm wrench to approx. 40-45 Nm.
Clean the threads with a brush to remove any remaining PTFE‑tape.
Add 2‑3 rounds of PTFE‑tape to the threads of the new steam wash nozzle fitting
(1).
Connect the steam hose. Tighten with a 9/16 in wrench.
