Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum Need help troubleshooting my Dampp Chaser system

Hi everyone. Thanks in advance for your help. Here's my situation. I had a new Dammp Chaser system (H5 system with humidifier and dehumidifier) installed into my upright piano a couple months ago. I live in New England so it is getting cold and dry.

My hygrometer next to the piano is saying 69 degrees and 22% humidity. I thought to myself, "wouldn't it be cool if I put my hygrometer inside my piano, came back the next day and saw a reading of 42% humidity". I tried this experiment and my reading came back inside the piano at 25%. I had the hygrometer on the bottom of the piano right under the humidistat.

So I'm a bit bummed by this and now I'm doubting whether or not my DC is working properly. I've been changing the water every 2.5 weeks roughly and the pads are wet and feel slightly warm. The dehumidifier bar is not hot. The power light is on and seems to be getting electricity.

I ordered a higher quality hygrometer that should arrive in a few days but still the problem I have is that the humidity inside the piano is almost the same as outside.

I called Dampp Chaser and they said that the installation wasn't exactly right. The humidistat should be 2" above and 2" to the left of the water tank. My humidistat was much farther away. I slid the humidistat closer but it hasn't made any difference in the last 8 hours.

Dampp Chaser was very nice on the phone and sounded like they would do whatever it took to get it to work but at this point their only suggestion was to move the humidistat.

Any idea what the problem might be? Has anyone had this same issue?

Thanks!

was the system installed by a piano tuner or technician, if so then you should call them back to check the system

The system was installed by a technician but I'm not sure what he would do if he came over to look at it. My gut feeling is that there is something wrong with the unit but I'd like to do the testing myself to help come to that conclusion. I've looked at the unit myself and looks correct to me. (I know I'm not a piano technician, but this is really more of an electrical/electronics installation in which I'm fairly well versed.) Also, given that the technician didn't install the system based on the directions included in the unit (regarding location of the humidistat) I'm not sure he is going to be the right person to help troubleshoot the system.

Because the system is so simple, I'm assuming there is an issue with the built-in humidstat in the DC system, but I'm curious to see if anyone has had similar experiences that I can learn from.

Cheers.

I suspect the problem is with your hygrometer. As you say, the system is in principle quite simple. If the humidity is too low, the humidifier bar is turned on and this is what you are seeing. So, the system is working.

For accurate measurements, I suggest getting a humidity data logger, available online.

Remember, even the DC system is not a cure-all for humidity issues, rather, it mitigates the problem.

That was my first thought so we'll see what happens when I get my new hygrometer. I ordered a fairly expensive one that is certified to be pretty accurate. It would make my current hygrometer about 20% off. Certainly possible.

The only glitch with this logic is that theoretically the DC cycles on and off and moves the RH% up to ~50% and then down to the high thirties. I reset my hygrometer to record min/max and there were no fluctuations over the two day test.

Of course if my hygrometer reading is innacurate maybe the min/max is too. We'll see what happens with the new hygrometer.

One more thing I forgot...there is about an inch of space between the top of the bottom panel and the underside of the piano. I'm wondering if that space is allowing leaking humidity in some way. Not sure it would be significant enough.

the Dampp-Chaser has a five year warranty, call your tech, he knows what to do.

You say you "change the water" every 2.5 weeks -- what do you mean by this?

Normally you don't actually "change" the water - it evaporates on the pads, the light goes on, and you refill the tank.

I'm not trying to be nit-picky - just trying to understand if the unit is actually using water or not.

In mine, on a grand, in the winter I may need to fill it about every week.

Sorry. To clarify I fill the water tank every 2.5 weeks so it is doing something...the question is whether it is doing enough.

If the piano was tuned before the change of season, is the piano holding tune reasonably well after the change of season? If so, the D-C system is doing its job.

If the piano was tuned after the change of season, did your tuner need to significantly raise the pitch when he tuned it? If so, then you do need additional troubleshooting. It may be the unit. But I think this is unlikely. If you are having tuning stability issues, you might want to consider supplementing you D-C system with a room humidifier during the winter.

Edit: One full inch between the bottom panel and the keybed... that is a lot.

I have a similar problem with my system. The min-max readings are just too far from the theoretical 42% RH.

I asked Dampp-Chaser and they told me that what matters is the average humidity not the isolated readings. But I had no humidity data loger in order to check the average humidity in the piano.

My piano holds tunings very well. So I guess the system is working fine.

I have to add water every 2/3 weeks depending on the weather.

dcb,

Once you get that new hygrometer, please post your findings here. I'd be very interested to read how things worked out. I'm considering to install a DamppChaser, but my piano also has a gap of about 1" between the bottom panel and the keybed, and I'm wondering whether this would "leak" too much humidity.

You could opt for a back cover, that would help.

Gadzar, I find DC's statement illogical to me. The DC should maintain the RH to between roughly 38% and 50%...sure it will not be exactly 42% all the time but it should be in that range. So an instant reading of 38, 45, 50...would make sense.

However, a reading of 25% where the min/max doesn't change is clearly too low and the average is not anywhere close to 42%.

The other part of this discussion that I feel strongly about is that the piano and the tuning is independent. Obviously, the reason to get a DC is to protect the piano and stabilize tuning but having a stable tuning does not imply that the DC is working. Conversely, an instable tuning doesn't mean the DC is not working. (there are just so many other variables around stability/ age of piano, new strings, how hard you play, how often you play,etc.)

This is why my simple test is just to measure the RH inside a fairly small box with a DC in it.(my piano) I'll update the thread when I do the following tests:

-improve the accuracy of my RH measurement (new/better hygrometer)
-experiment with the location of the humidistat
-seal off the 1" gap above the bottom panel
-hopefully it won't come to this but maybe replacing the humidistat with another unit from DC

Should be an interesting project. I care about taking care of my piano so it will be great if I can determine that the DC is actually improving the conditions inside the piano.

Cheers.

Don't worry about it. I install D-C's all the time into grands, and the whole soundboard is exposed on the bottom and the top! Uprights have the whole soundboard exposed at the rear.

Uprights are easier to control, because they're much more of a box.

Measuring humidity inside the piano is the best, but it's even easier for most people to measure the pitch of your piano. There are many apps out there that will do that. The A above middle C should be at 440 Hz... how is this changing? If it's really that dry, it should be going flat.

This is the best indication of whether the D-C system is holding humidity within range over time.

--Cy--

Another reason your hygrometers reading may be low is that you stuck it in the bottom of the piano. I would imagine that to be the driest area because the warm, moistened air rises and disperses. Instead of just putting the hygrometer in the bottom of the piano, find somewhere up higher.

Also, I agree with Cy. The proof is in the pudding. If your piano was really running that dry you would definitely hear it.

You can download Tunelab shareware free. I think it would be interesting to measure all the Cs on your piano once a week. It can be an eye opener to see what your tuning is really doing.

So, why would you need a new humidistat? In dry weather, the heating rod is turned off and the humidifier is turned on. The humidistat is doing its job.

You don’t want the humidifier bar to get hot and put out too much moisture too rapidly. After all, you do not want to cause rust and corrosion on metal parts like the strings.




If you check D-C’s own advertising, you’ll see that one reason they recommend their systems is for stabilizing tunings across seasonal changes. http://www.pianolifesaver.com/english/pianohumidifier.php

Yes, a piano that is still at pitch after going from a humid summer to an extremely dry winter absolutely implies that the D-C unit is working correctly.

Dampp-Chaser today released a service bulletin about some H5 humidistats sticking in the humidify mode. If yours was recently installed, your tech will likely be contacting you to check and see if its one of the affected ones. He can then check the system while there.

So I have my new hygrometer and have more accurate readings now. The hygrometer I bought is from a labaratory store and is certified to be accrate +/- 2% for relative humidity. It also reads from the main unit and has a wireless sensor I can put in the piano. This was a good purchase...now I have some confidence.

I've had it in place for about 6 hours now and it is very responsive. In fact if I hold the unit in my hand, the temperature and humidity goes up a bit.

Outside the piano my RH% reading is 22%.
I have the wireless sensor velcroed directly on the humidistat inside the piano and it is reading 32%. (note that when I had the wireless sensor out of the piano next to the main unit, both read the same % so they are calibrated.)

So based on my observations with good measurement for the first 6 hours, it looks like the DC is doing something, but not enough. So I'll monitor it for a while and try and figure out what is going on.

My guess now is either the 1" gap above my bottom panel is letting in too much dry air or the DC is incorrectly calibrated to ~32% instead of 42%....or.... I'm missing something. I'll keep you posted.

a 1" gap in the lower panel is not going to make a differences. All upright pianos have a gap in the lower panel. I have installed Dampp-Chaser system in many upright pianos . I tune these pianos once a year and the pitch is almost bang on.