Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum Humidifier needed in San Francisco area?

Again, unless you know how the Dampp-Chaser system works, your speculations are probably not doing you much good, nor your piano. And again, the proof is in the pudding; if your system has kept your piano very stable in tuning for 14 years, it has been doing its job very well indeed.

A little explanation may help you to understand a bit better. You can also visit the Dampp-Chaser website for more information. I think they have some of their studies available there for review.

The Dampp-Chaser is not a laboratory instrument which demands precise calibration. The Dampp-Chaser works by reducing the effect of humidity swings in the piano's environment, not by controlling humidity precisely. This works with a relatively simple device like the Dampp-Chaser because there is a lag time for the wood in the piano to absorb water vapor from the air, and to release water vapor into the air.

I just moved to my place in Alameda a year ago and the stability persisted even after 5 months without the DC. (In July 2005 my technician was surprised that it remained in tune without the DC.)

Turning it on NOW would lower the humidity 10-15% and might drive it out of tune! As well as increasing the heat in the flat...

I checked the DC site but it's not very technical. I may have missed the studies (or comments about "studies") but I'll check again. In general, it seems more helpful to see studies written up by non-affiliated researchers.

I understand from these posts that the consensus among technicians swings in favor of installing a DC in most areas in the country in most pianos. But a few of you didn't think it critical in many cases.

The Dampp-Chaser will not lower the humidity in your piano by
10 to 15%. What is critical is the equilibrium moisture content of the soundboard, which will vary an exceedingly small amount with or without the Dampp-Chaser. The heating element input rating is 15 to 25 watts. Your dog's or cat's body radiates more heat and heats your house more than a Dampp-Chaser would.

You might wait until the first rains of the fall to turn on the Dampp-Chaser. It might help suppress the small effect the change of humidity will have on your piano's tuning.

I guess the technical Dampp-Chaser stuff is on the part of the company website that is not available except to technicians. You will no doubt find all the technical information you want about Dampp-Chasers if you take the time to email the company with specific questions or search the Piano World archives or the PTG Pianotech archives.

Thanks for your comment about the 15 to 25 watts. Then perhaps something is wrong with my DC unit. The dehumidifier got MUCH hotter than body heat and I was alarmed enough to change my mind about using it. Perhaps the capacitor is defective.

If you can fry an egg on it, it is doing a REAL good job of "chasing damp" away.

There is very likely nothing wrong with your heating rod. Temperature of the heating rod and wattage input are not directy related. The heaters in Dampp-Chaser systems are designed so that they cannot cause burns.They do get hot to the touch in normal operation. I should also point out that just because your dog or cat is not as hot to the touch as your Dampp-Chaser does not mean that they are not contributing to heating your house more than the Dampp-Chaser. You may be able to understand this if you imagine having a large number of people in your house, say 50 or 100, so that your living room and adjacent areas are packed. Your house will get very warm, and you will have to be sure to open all the windows. Yet none of the people in your house will be noticeably hot to the touch.

Frankly, you would do best to simply leave your Dampp-Chaser diconnected and to have it removed from your piano at your next tuning. It sounds like you are getting quite upset about something whose operation you do not understand. Better to put all that anxious energy into playing and enjoying your piano, rather than worrying about your Dampp-Chaser. Dampp-Chasers are not all that critical in this part of the world.

Happy playing!

I think I would agree in this case, Mike. One of the most irrational statements I ever heard was from a psychiatrist who regularly administered shock therapy to his patients. He certainly never wanted to experience what he did for a living. He was afraid he would get "shocked" by his piano. One woman who is an injury attorney was afraid that when she watered the piano, an electric shock would travel up the tube and shock her.

As for the heat, the D-C unit emits no more total heat than an ordinary light bulb. Even the computer emits more total heat than that. How about all of the electronics we all enjoy? My DVR gets hot enough to fry an egg. A refrigerator also regularly pumps heat out into the room. The heat that a DC unit produces is quite negligible.

Well.... it WOULD be a telling experiment to leave it disconnected for a few years... to get a fair idea about tuning stability with and without its use.

Part of my "upset" is that I AM looking for an excuse not to use it for awhile... knowing that my technician's reaction to disconnecting it will be a bit unpleasant to deal with. But this problem - the tuner-tunee relationship - is a whole other topic!

You would'nt need a few years. About three weeks will do just fine. Disconnect it, and report back here in three weeks. Tell us how the tunings held up.

In response to Curry: Tuning held up fine after 5 months of no use, surprising my technician last year. But that was a year ago. Now, the tuning sounds just fine to me, but I don't have the experienced ear/tools of my technician.

My query here began because I have an upcoming appt. with my technician, and I was wondering whether to set up the DC before he came so it could equilibrate before his visit.

The tuning has been remarkably stable on this piano. My technician has rarely spent more than 45 minutes working on it.

Bill, yesterday I used your CA method instead of epoxy on a bass bridge crack on an old spinet, and it worked great -- thanks!

--Cy--

Great! I'm glad you could use a method of repair appropriate for the situation and find that it worked adequately.

I have a dampp-chaser on my 2004 Steinway B and I run a dehumidifier 24/7. I live in Daly City, Ca. just outside of San Francisco and about a mile from the ocean. In my experience this extra attention to the humidity level in my house has made all the difference. However, it costs about $50 a month to run the dehumidifier. Has anyone here heard of the company Humidex atlantic and if so, do you think installing one of their products would be a better way to go. They claim the cost to run their system is $3 a month. Perhaps too good to be true.

If you have the Dampp-Chaser, you shouldn't need the dehumidifier at all: that's one of the system benefits.

If it's not working well enough without the dehumidifier, get your tech to add more heater rods, or add an undercover. I like to use at least 100 watts total (which will still be a lot cheaper to run than the dehumidier: just like a light bulb). A seven-foot piano might need three or four rods.

--Cy--

Dave Stahl says "The fact is, it isn't going to hurt anything, because the humidistat will shut off the current when the humidity gets below 42 %. I have never found a need to recommend a humidifier."

The matter is that the Dampp-Chaser system comes with both a Humidifier and a Dehumiditier and both operate to control the RH at a low level such as 54 down to 48 or so on my piano. I check the two during the day and it seems to work well. Though if the room gets overheated by the Ambient Temperature the D-C system struggles to lower it much under about 59 RH. I then have to use a room de-humidifier to help matters.

Alan

Alan,

Dampp-Chaser systems are custom-configured for each installation. Some people in certain areas, like Dave, don't install the humidifier side.

Likewise, your system can be custom-configured. More or bigger heating rods can be added to let the system handle humidity better. An undercover can be added to concentrate the air around the soundboard and make the whoe system more efficient. (This is for a grand; an upright can have a back cover added.)

--Cy--

I think that people worry about this dampp chaser system to much. When pianos are built at the factories, they get put into large rooms. Then they are crated and picked up and shipped to a port. They are then put into containers that are not climate controlled and stay hold up for sometimes weeks. Then the containers are put on a ship for a 3 or more week trip across the ocean from asia or Europe. Then the containers are once again sitting at the port waiting to be trucked across the country to importers or directly to dealers. Then the pianos are at the dealers sometimes for months or years before being sold. All of this without the aid of a Dampp Chaser system. I would think that because pianos are subjected to heat, cold, dampness etc from factory to ones house, that they would start falling apart during the journey. But they don't do they.

True. And they don't fall apart due to high humidity, they just get sticky. Keys get sticky, they don't return. Damper felts get sticky as if you are playing with the sostenuto pedal down all the time. Not very desirable, is it?

If the wooden sound board is exposed to extreme low humidity for a long period of time, then it can crack. But I think this case is rare if that ever happens at all between the factory and distribution point.

You're right; they are subjected to extremes during the trip. Most Asian pianos are sealed with plastic inside their crates, so humidity doesn't change during the trip (but relative humidity changes with temperature).

However, in the last month I have seen two new pianos on the showroom floor with cracks in the soundboard. This isn't because of stress during shipping; it's because the wood wasn't seasoned properly.

Humidity swings take a long time to cause damage, generally. It's more like the difference between parking your car outside and parking it in a garage. Outside, the paint will fade and crack, the dashboard will crack, and the upholstery will fade. All of these (especially re-painting) are expensive fixes. Since people usually keep pianos much longer than they do cars, it's worth it to protect them over the long run.

There's no good car analogy with the short-term effects on tuning, though. And there's no sun damage that keeps the car from running, unlike a cracked pinblock in a piano.

Haven't you ever had doors or windows in your house stick from humidity? Or dresser drawers that are hard to open and close?

--Cy--

　Are these all true? I have been thinking one or two dozens of crated pinas are picked up by a reefer container at the factory and the temperature of the pianos are kept constant all the way until the container is pulled to the dealership's headquater building in the destination country. Of course, the door of the container may be opend for a few times for customs inspections.

---
an amateur