I'm getting a Valve Comm Fail after upgrading my software on my APA6000 unit. How can I resolve this?

Document ID

Document ID TE2359

Published Date

Published Date 21/01/2019
Question
I'm getting a Valve Comm Fail after upgrading my software on my APA6000 unit. How can I resolve this?
Summary
APA6000 and valve comm fail
Answer
"Valve Comm Fail" warning appears after an upgrade was performed to the APA6000 analyser. It seems the analyser is more susceptible to this error after the upgrade, though it is unlikely due to failure of any parts.

In time, a surface film can develop on the wire harness connecting plugs and pins. This film causes contact resistance, and results in 'noisy' connections.

Cleaning of a 'noisy' connection will restore normal operation. In almost all occurrences of the "Valve Comm Fail" warning, the fault is in the wire harness connection to the backplane circuit board on the front panel. Disconnect and reconnect the wire harness plug several times; the scraping action of disconnecting/reconnecting the contacts will clean them quite sufficiently.