Temperature Control

A piano functions best under fairly consistent conditions which are neither too wet nor too dry, optimally at a temperature of 68 degrees Fahrenheit and 42-45 percent relative humidity.

Changes in temperature will affect the metal parts in your piano. The strings and cast iron plate can change enough to make the piano go wildly out of tune. Heater vents, air conditioning, placement of the piano in your home and direct sunlight can “murder” the best tuning a technician can give.

Electronic tuning devices (ETDs) are so sensitive they can even measure changes in pitch from just touching a string with your finger. Your body heat is higher than the ambient air temperature in the room and touching it makes the metal expand or elongate, making the pitch lower. This is a small change and when the temperature of the string returns to room temperature after a couple of minutes, it will return to the original pitch.

During tuning, tension is equalized along each segment in a string. These segments have different purposes, and are separated by friction points where the string makes a bend. The friction points are important in that they are responsible for keeping the piano in tune. When large changes in temperature occur, the stings and plate change enough for the friction points to shift, causing the piano to go out of tune. It is then necessary to re-tune the piano.

When temperature control cannot be achieved, such as during the winter in a church where it is heated once a week for services, I recommend that the piano be tuned at service temperature (the temerature it is during the church service). This enables the dimensions of the metal to be similar and the pitch to be closer to when it was tuned.

Because temperature changes drastically affect humidity, I hightly recommend a Dampp-Chaser Humidity Conrol System.for a piano in an environment where the temperature fluxes at least 10 degrees.