The piano is an imposing piece of furniture to say the least. While it may seem sturdy, it can be the source of many headaches (if not heartaches) if left unchecked. Of the many problems that do arise from improper maintenance, moisture is one of the most harmful. It is therefore very important to control it. One very useful tool serves this purpose, too, and it should certainly be considered by anyone who owns or intends purchasing a quality instrument.

Figure 1 : The Dampp-Chaser System

   A piano is a very sophisticated and highly complex construct made of such varying materials as metal, felt, and plastics, not to forget wood, its most prominent component. Like all organic substance, wood is very sensitive, and very much so in relation to its surroundings. Canada is a land known for its marked, if not drastic seasonal changes in weather, with its blistering summer heatwaves, damp and cool falls, and frequent spine chilling winter frosts. Under such conditions, a piano is much at risk, its main nemesis here bring the constant shifts in humidity. As the level of moisture rises, wood expands, but contracts in a dry environment. Piano owners must reckon with these realities and their consequences, and failure to do so will ultimately lead to serious issues in upkeep. In the first case, excess moisture, piano keys will have a tendency to stick or, worse, strings will start to corrode (to name but two issues); conversely, a soundboard will start to warp and even crack in too dry a setting.

   To prevent all of the above, a certain level of moisture need be maintained. Experts in the field claim that a RH factor (Relative Humidity) of 42% is the ideal value. Yet, there is nothing to fear if the level varies, as long as it stays within a range of 20% of that value in a given year. Not only that, but it can actually ensure better stability of its tuning.

   There are two ways to maintain that value. The first is to install the instrument in a setting (private home, concert hall) equipped with a central humidity control system similar to those for heating and air-conditioning. But such set-ups are few and far between, at least in private dwellings.

   A much more efficient solution to the problem is provided by its alternative, namely, the Dampp-ChaserTM system. This unique invention has proven its mettle in all corners of the world since its introduction in the market some 70 years ago. Its maker produces two models, one for uprights (figure 3), the other for concert grands (figure 2), the latter offered in slightly modified versions for smaller sizes and larger ones in excess of seven feet.



Its main components, as illustrated atop this page (figure 1), are the following:

1–Humidifier: Ensures the maintenance of proper moisture. A single reservoir, or two interconnected ones for large size grands, is filled  with water. Two pads hanging above it from a heating rod draw the water, which is then dispersed as a fine mist throughout the instrument.

2–Dehumidifier: Heated air currents are diffused to chase away any excess humidity.

3–Humidistat: This is the “brain” of the system. It is equipped with sensors that detect changes in moisture levels and activates either of the previous components according to need, most often in alternating cycles.

4-3 Light Panel

     Green light: Power on.

     Yellow light: Monitors water level in the humidifier. Flashes to indicate need for a refill.

     Red light: Pad monitor. Light flashes to indicate a change of these (every 6 months).

5–Universal Water Jug: for humidifier refills.

6–Watering tube: Connects jug to humidifier.

7–PAD Treatment solution: Prevents growth of algae and other organic products in the humidifier and watering tube. The maker recommends filling the jug first then adding the solution into it. 

   A few points must now be made with regards to the type of water used. There is much variance in chemical composition according to local supply systems, some waters being harder, others softer. When concentrations are high, deposits start building up in the humidifier and tubes, and corrosion can occur over time. Distilled water may well solve this problem, but this leads to another one. The humidifier, it must be noted, is equipped with two electrodes whose purpose it is to monitor the level of water in its tank. The current however needs minerals to conduct it between them. Without these, the yellow light will start flashing, even if it is filled. To allow the current to circulate, either one ads a capful of PAD solution or adding just a pinch of salt or glass of tap water on an occasional basis.

   The purchase of a Dampp-Chaser is certainly a good idea for those who have a vested interested in a piano. Professional performers are certainly aware of this, likewise for instrument makers, teachers or venue managers. But is also crucial to know that this system needs to be monitored, be it by a technician who comes by twice a year to give it a check, or by the owner/user. The latter can, for instance, set a cellphone alarm as a reminder to give a look to the humidifier on a weekly basis. It is a fallacy to think that all your worries will just go away once you have it installed. If it is not possible for a user to ensure follow up, it is best not to purchase the system at all!

  On the flip side of the coin, the dehumidifier is a most reliable asset, because it requires no maintenance and even helps to reduce variances in moisture levels by a third, a fact proven in lab tests.

  One last point must be made here, and an important one to know for anyone in the market. Some makers may void their guarantees, because they do not recognize the system’s installation on their instruments. The may also do the same in the opposite case, if the owner does not ensure the maintenance of a proper level of moisture for the instrument. It is therefore recommended to read closely the terms of the guarantee before buying the system or to consult the manufacturer of the piano first.

   It goes without saying, installing a Dampp-Chaser is best left to a seasoned piano technician. Lists of these are posted on the company’s multilingual Website by country and, in some cases, by regions (Canada’s provinces, for example). In experienced hands, installation takes on average an hour, sometimes even less (uprights, for instance). For best results, he will seal the underside of a grand piano with stiff material, or the backside of an upright. This extra step is not only beneficial for the instrument but its user as well, because he will not have to refill the humidifier as often.