Thanks for the info - yes, the side that is open is plenty large for ventilation but thanks for the heads up - I will monitor closely for a while.
I will just open one of the other valves with the line removed to dump air when I change to using one diffuser this winter. Just wanted to know if that was an acceptable way of relieving the pressure.
It works fine, but the constant hiss of escaping air is maddening. To a mechanic, anyway.
