I have an LP gas fired boiler, all copper piping, all base board heat.
Four zone control valves with four separate t-stats.
My question is how do I find a pressure leak in the system.
The leak is so slight that it may take weeks or months for the pressure
to drop below the cold pressure limit. But then I have to add water to bring
pressure up again. Needless to say, I have learned over the years how
to drain and re-set the expansion tank. The loss of pressure only
occurs when the boiler is running frequently due to extreme cold weather.
It's a nuisance and also bad for the system to keep adding new water.
So do I need to pressurize the system with air to somehow find the leak?