SSI BINARY SOLVENT DELIVERY MODULE, Operator'S Manual

 7-17 

6. PROBLEM 

SOLVING 

Quick Guide to Problem Solving 

You Notice

1. Uneven pressure 

trace. 

2. Pressure drops. 
3.  No flow out the 

outlet check valve. 

This May Mean 

1. Bubble in 

check valve. 

2. Leaks in 

system. 

3. Dirty check 

valve. 

4. Bad check 

valve. 

Possible Cause 

1.  Solvent not properly 

degassed. 

2.  Fittings are not tight. 
3.  Mobile phase not properly 

filtered. 

4.  Particles from worn piston 

seal caught in check valve. 

5.  Plugged inlet filter. 

You Should 

1.  Check to be certain that mobile phase is 

properly degassed. 

2.  Check connections for leaks by tightening 

fittings. 

3.  Prime the system directly from the outlet 

check valve. 

4.  Clean or replace the check valves. See 

Section 5.4. 

5.  Clean or replace inlet filter. See Section 

5.1.1. 

1. Uneven pressure 

trace. 

2. Pressure drops. 
3.  Fluid between the 

pump head and the 
retainer. 

1. Leaks in 

system. 

2. The piston 

seal or 
diaphragm is 
worn. 

1.  Fittings not tight. 
2.  Long usage time since last 

seal / diaphragm change. 

3.  Salt deposits on seal or 

diaphragm (especially if 
buffered aqueous mobile 
phases are used). 

1.  Check all connections for leaks. 
2.  Replace piston seal & diaphragm.   See 

Sections 5.2 and 5.3. 

3.  Check the piston for salt deposits. Clean as 

necessary. See Section 5.2.4. 

Pump makes a loud 
clanging or slapping 
noise (intermittent 
contact with cam). 

Piston carrier is 
catching in 
piston guide. 

1.  Cap nut screws on the pump 

head are loose. 

2.  Seal(s) are worn. 
3.  Piston guide is worn 
 

1.  Check cap nut screws on pump head. 

Tighten if necessary. 

2. Replace seals. 
3.  Replace piston guide and seals. See 

Sections 5.2 and 5.3. 

No power when pump 
turned ON. 

Blown fuses in 
the power entry 
module. 

1. Power surge. 
2. Internal short. 

1.  Replace only with the appropriate fuses (1A 

for 100/110 Vac or 1/2A for 220/240 Vac). 

2.  Contact service technician if problem 

persists. 

Blue dye in mobile 
phase. 

Pulse damper 
diaphragm has 
burst. 

Sudden pressure drop when 
purging system. 

Replace pulse damper. See Section 5.5. 

Pump runs for 50 
pump strokes, then 
shuts down. 

Lower pressure 
limit is 
activating. 

1.  Mobile phase is not properly 

filtered. 

2.  Particles from worn seal 

trapped in the system (e.g., 
tubing, filters, injection valve, 
column inlet). 

1.  Check to be certain the low pressure limit is 

set to 0 psi. 

2.  Only increase the low pressure limit after the 

pump attains operating pressure. 

3.  Contact service technician. 

1.  Pump shuts down 

after run is called 
even with no 
column connected. 

2.  Pump runs to 

maximum pressure  
and shuts down. 

Clog in fluid 
system. 

1.  Remove and clean both the inlet and 

bulkhead filters. See Section 5.2. 

2.  If the problem persists, remove tubing from 

system one piece at a time until you find the 
clogged piece. Most clogs occur outside the 
pump itself. 

No power when pump 
turned ON. Fan does 
not run. 

Blown fuses in 
the power entry 
module. 

1. Power surge. 
2. Internal short. 

1.  Replace only with the appropriate fuses (1A 

for 100-120 Vac or 1/2A for 220-240 Vac). 

2.  Contact service technician if problem 

persists. 

Front panel appears 
OK but pump motor 
does not run. 

Blown fuse on 
the motor power 
circuit board. 

1. Power surge. 
2. Internal short. 

1.  Replace only with the appropriate fuse . 
2.  Contact service technician if problem 

persists. 

PEEK fittings or 
components leak. 

You cannot 
force PEEK 
parts with 
interference to 
seal by brute 
force tightening. 

1.  Film of fluid between 

surfaces. 

2.  Salt crystals between 

surfaces. 

3.  Scratches in mating surfaces. 

1.  Clean and dry mating surfaces. 
2.  If scratched, replace defective part.