1) Turning OFF: Push this circular knob (red)

2) To Restart:

1) Rotate the same circular knob like half a turn clock-wise then it will be released (see the picture above)
2) Press the red button on the (right hand) panel to clear the alarm → Press the green button → HR3 will

...

start afterward if there is helium flowing to it.

Reasons for automatic turn-off, and how to restart.

...

Date	Person	Note
07/05/2022	Sam	“ The main reason why the compressor wouldn’t start is if the system is at maximum pressure already or if it did many starts in a short period of time (6 + / hour I think). The system would instantly restart when PC1 > 0.7 even just after it stops due to a lack of pressure rise in PSW4.”
08/09/2022	Sam (and Ishara)	Buffer Tank Max Pressure was set to 250 psi (max allowed although Sam asked to change it to 999 psi).
07/28/2022	Adam	“ The check valve here acts as a pressure maintaining device. For example, in a situation where the storage tanks outside are empty. This check valve keeps a minimum of 50 psi in the HR3’s loop and buffer tank. When the pressure in HR3’s buffer tank reaches 100 psi, the solenoid valve SV7 will open, allowing free flow from the buffer tank to the storage tanks. This will discharge the buffer tank quickly until the pressure reaches 80 psi, then it will shut. It will keep doing this until the pressure in the storage tanks outside go above 80 psi at which point the lower set point will never be reached and SV7 will stay open. “The clicking that you hear from the HR3 may be the sound of the buffer tank unloading to the storage tank. The higher the incoming flow to the HR3, the higher the frequency of the clicking sound”. “ This model of recovery compressor is rated for 53 scfm at 125 psi. Any incoming flow above 53 scfm will be vented, but the compressor will continue to run and recover 53 scfm.”

HR3 LCD screen

If you want to run the HR3 more or less continuously you could try to do the following.
Increase Sample Time Period and Spacing. (Now it checks pressure increase every 10 minutes, if you set it to an hour, it will only check every hour)
Decrease Max Pressure Rise (Minimum pressure rise detected in buffer tank to keep the HR3 operational, if it's set lower it's more likely that it will keep running 24/7)

...

Ishara changed both the Sample time period (minutes), and Sample Spacing (minutes) to 15 minutes.