Source intake sediment removal.
Gravity fed water system airlock.
The bladder breaks or leaks and no longer maintains system pressure and needs to be replaced.
New stove gravity system airlocking.
Airlock in primary hot water circuit power flushing old gravity fed indirect system.
To get an airlock out of either the cold or the hot water you require a water pressure more that the pipe that has the airlock in so that there is force pushing the airlock away.
If the holding tanks get drained an airlock always developed and i just loosen the band clamp to let the air out again.
The spring loaded valve works in opening and releasing high pressure and air during extreme system pressure.
It sounds like such a simple theory too.
I am not getting any hot water from my hot water taps two showers which are fed from a water pump.
And today in many parts of new zealand where access to power is uneconomic or impossible gravity fed water systems are still used to keep water flowing to troughs and homes.
There are four basic elements to a gravity water system.
I have a gravity feed water system to a mountain cabin.
The system was fine for 40 years going back before my time but due to gradual settling there is now a place where airlocks regularly develop.
Having lived on spring water that was fed by gravity for over 50 years i have some experience in making these systems work and easy to maintain.
I am not a qualified plumber just a frustrated consumer.
Long before there were complicated electric pump systems for rural properties there was gravity.
I hope that my simple overview will help you design build and enjoy a gravity fed system too.
Examples and references are given.
Gravity flow design construction gravity flow water systems.
Gravity systems are simple but very complex at the same time.
Plumbing forum plumbing advice.
Plumbing forum plumbing advice.
When the hot and cold water is gravity fed then by crossing the water over will make getting the airlock out of the pipes virtually impossible.
If power is a problem gravity may be your best bet for a reliable water supply.
Air lock best practice prevention.
Calculating water flow pipe size understanding air locks and using siphons are covered.
The tank fills with water and presses against a rubber bladder pressurized with air which fills and empties in response to system pressure.
Useful factsheet from the british colombia ministry of agriculture and lands detailing the problems and solutions of gravity flow pipe system design.