How to check purge flow?

Get the [flowmeter] and purge any vial (I usually test this with a BFB vial). You do not need to bake the trap out before testing this, because you'll have to bake it out after purging the test anyway. There's a sticky note on all the concentrators that has the purge flow and last test date written on it (most of the concentrators will have a purge flow around ~35-40mL/min). Anything lower than ~20mL/min indicates a problem with the purge flow.

Possible causes

Plugged/damaged needle

This is the most probable cause for low purge flow. Sometimes this happens when sediment from a sample clogs the needle holes. When this happens, you [flush the needle]. If that doesn't work, use the [leak detector] to check the needle for leaks because it's possible the needle is broken (especially common at the curvy parts on top of the needle). If the needle is damaged, get a new needle (make sure the top is the correct shape - there are square and hexagon-shaped needles used in this lab).

Improper water management installation

I don't find that this really affects purge flow itself, but sometimes when reinstalling the parts that connect the water management to the valve, the transfer line screw that goes into the valve doesn't seat properly so there's a leak (but it's too small for the concentrator to detect so it won't screech). Use the [leak detector] to check the valve to make sure it's installed properly.

Improper trap installation

This one isn't common since the concentrator will start screeching if it detects a helium leak, but it can happen with some of the concentrators (especially the Solatek on F4). Most likely you didn't insert the trap fully before tightening the screws, or the screws themselves weren't seated properly. Turn off the concentrator and reinstall the trap.

Improper transfer line installation

Usually Diem or Robert change the transfer line, so if this is an issue they'll fix it.