The last few times that I have depressurized the water lines for my Elektra machine I have ended up with a thermosyphon stall, with the evidence being that I am unable to achieve a flash boil at the group despite hours of warmup time (normally I see a flash boil within half an hour). I remember reading somewhere that Marzocco group caps must be disassembled and primed all the way to the top to prevent air from getting trapped - is the same required for Elektra groups if any air is introduced into the system? The highest point in the system, the chamber at the top of the group, has an area that is not in the direct water path where an air pocket can hide if any air enters the system. It seems like the only way to get group performance back to normal is to:

1. Shut off the water supply
2. Remove the group cap
3. Crack open the water supply to fill the group chamber (the area with the flow restrictor and black cylindrical filter) until the chamber overflows just a tiny bit
4. Tighten down the group cap when the chamber is completely full and allow the water to overflow out a bit (to ensure that there is no air in the chamber)
5. Turn water supply back on

Does anyone have a better alternative, or am I the only one who has run into this problem? The last time I removed the group cap, I snapped the gasket that seals it (fixed by a $0.40 O-ring from the hardware store that fit well enough). While this issue only comes up if I have to disconnect the water supply, it definitely isn't convenient to have to remove the group cap nut.

Thanks!

one way valve (also called check valve) on the water line attached to the unit

So this would be a check valve between filters and the machine? There is a check valve inside of the machine between the four-way solenoid and HX water inlet, but I guess the point of that check valve would be to prevent air from getting to the pump?