Morning. It's been a while since this thread was active, but I'm pursuing a project like this and at the moment am planning to follow this design. But I have a question.
In my earlier thinking I'd laid out my own system in a way that used only one PID controller and temperature sensor - the...
Hi. I'm preparing to put together a HERMS brewing setup. I'll use manual valves initially, but may replace them later with automated valves and go full auto. This system uses one PID controller that always controls the HLT heating element. You can see a schematic of the flow layout here...
I don't think air would flow back in when it vented. My only concern is when it's in steady state "non-venting" condition. On one side you have gas pressure and on the other side the spring, with the forces balanced. You're right on with your physics. But your seal has to be perfect or gas...
Well, looks like a tire gauge works exactly like you describe. You could make your gadget by drilling a tiny hole in the side of a tire gauge as a relief port. You would have to guess exactly where to drill it, though.
I still don't know if the seal between the cylinder and the plug would...
I don't think you could get the cork or flap to hold a seal well enough while still moving in response to the pressure differential with your brass tube gadget. You would need it to be pressurized on one side and not on the other and stay that way for a "long" time. If the thing is loose...