Treating High Humidity in basement

Hi : I live in Massachusetts and have my second system in my basement and have a De-humidifier in the room with the system...I leave it on all the time from May - November...The only time I shut it off during the damp season is when I am down listening..After listening I turn the system back on..I try to keep the room Humidity about 40 % .. Any quality Dehumidifier in the room should work..Just make sure it is large enough to do the whole cellar...It shouldn't be a big deal.......

The floor heat system may be the sticking point. An appropriately sized dehumidifier works fine in our house, but we have forced air heating/cooling. During the cold months, the forced air heat dries the air so that the dehumidifier is not even needed. I am not familiar with your floor heat system (assume it is hot water in pipes, but could be glycol in plastic tubes?), but the temperature differential between the heated room and the surrounding ground will contribute to a migration of water vapor into the room. If there is not an adequate vapor barrier below the slab, you could be bringing significant moisture from the ground into your basement area. Moisture vapor will also migrate through the walls if they are not damp-proofed. I believe the best place to start would be to purchase a good quality, moderately large dehumidifier and let it run for a week or so then see what you think. It sounds like you own a hygrometer, so you can measure the relatively humidity at incremental distances away from the dehumidifier to check the effective radius of treatment. Depending on your basement layout, you may need two dehumidifiers. The next step would be to install some form of forced air ventilation system, but before doing anything like that, I would consult an HVAC contractor. In fact, I would probably call a contractor as soon as I determined one dehumidifier alone was not going to work.

Dehumidifier is very commonly used in Asia, almost every family has more than one in Taiwan. Not popular in US and difficult to get, price is also very high. In Taiwan, you can pick one up for less than US$100.

Leave it on all the time, they don't pump continuously and only turns on when needed. Very effective, doesn't consume much energy, protect your investment with very little spending.

What do you mean a room De-humidifier is not poular and hard to get in U.S.? You can get them at any Home Depot, Lowes, Sears, Hardware stores......I have one in my current house, the house I bought has one and many friends have them, we have a drain hose hooked up to ours so you dont need to drain the pan.
Yhis a popular and easy to get solution, Semi's take on this puzzles me.

Thank you all for your responses. Not having time during the week due to work and a long commute, I have been checking here and other places to see what should be the best way to tackle this issue. First off, I bought a Value Home dehumdifier, 20L/15 hours is the rating. Well after plugging it in for only 70 minutes last night, the room went from 67% to 60%....and the machine is actually quiet. I also turned off the floor heat entirely, and opened the windows this morning to air it out. So I guess I have a process so to speak to exchange air manually, by opening the windows to allow the stale air out and using the dehumidifier once in a while when the levels start getting high. The device draws 450 watts in use. About the same as both of my tube amps in an idle state. I think this will be my solution for a while. Thanks all.

Thanks,
Audioquest4life