CO2 Solenoid/Regulator Problem?

[tawauboy]

remove the diffusor from your setup.
energize the solenoid to allow co2 to flow.
check whether co2 stop flowing after a while and does pressure gauge drops to 0?

you mentioned that you have used the regulator for 10 years.
the regulator valve may suffer from lack of lubrication, weakened spring or dirt accumulation. check with lfses or companies (deals with compressed air) if it is possible to service the regulator. if not, it may be time to retire your faithful regulator.

[pususuti]

Thanks Thomas. Pressure gauge dropped to "0." Going to buy a new regulator. Many thanks to all who had contributed. Appreciate you lot.

[pususuti]

New regulator working fine. Thank you again guys.