The auto sampler model G1329B 1260 is having high back pressure without column.
So far we had been doing the following:
- Rotor seal is replaced
- Injection valve is cleaned
- Metering Head is cleaned
- Sample Loop is replaced
- Needle seat is replaced
- Needle is replaced
- Pump is cleaned too.
- All tubing lines connected to the injection valve were check one by one. Not clog
- It's noticed that not solvent is coming out from the injection valve to the column compartment.
- Warm water was used to flush the system without column.
After all this procedure steps the back pressure still high.
What else we can do to prevent this issue again?
I noticed that several users have the same situation with this 1260 auto sampler.