Good question, Blogger. Since this is a problem for every church and synagogue, there must be a solution. I mean, except having it tuned frequently. For violins, you can buy a simple rubber hose device that fills with water. It is inserted through the openings in the violin and acts as a humidfier in dry climates. Then there are violin cases that protect against the climate changes. These are expensive, but necessary for high quality instruments.
That's what this Dampp Chaser is like. It fills with water and has a sensor as to whether the wood is too moist or too dry and alternates accordingly. I am wondering too, I know to dry it out the heater would be on, but what if you have drier conditions from central heat that maybe linger in the sanctuary even though the physical temperature is rather low??? Or does the humidifier part use heat also? I know we are out of tune a lot even though it is tuned at least twice a year, sometimes more.