This is knowledge and experience speaking, not supposition...
I have had numerous opportunities over multiple decades in the upper midwest to observe pianos which have been left in unheated spaces such as summer camps, personal cottages, and the like. In all cases the pianos fared better than had they been subjected to the extreme drying inherent in heating homes in the winter when the temperatures can be below zero F.
In fact, there should be no ill effects from freezing to the function of the piano. There could be finish damage, but that is not likely. Finish damage typically comes from "temperature shock" where there is a sudden (matter of minutes or hours) change in temperature -- like being in an unheated truck for hours and then being brought back into normal room temperature.
Condensation happens when there is a temperature differential -- typically an object that is colder than the dew point of the ambient surroundings. This doesn't happen with the slow cooling off of a building with a piano inside. The piano will be warmer than the air until slowly equilibrium is reached. In the spring, when things start warming up, the air will be warmer than the piano but the change is so slow that the piano will not be a large amount colder than the air. With a minimal temperature differential, there is minimal likelihood of condensation.
Also, after this experience, tuning will be on pitch and quite stable because the piano has not experienced the low indoor humidity (below 10% is not uncommon) that wrecks pianos in heated environments.
However...
That is not to say that these situations are completely without peril. Although the piano will be fine with the temperature change, it may not be fine if pipes weren't drained and they burst. Also, animals like to come inside because even though unheated indoors will still be more sheltered than outside. Mice can sneak their way in but even worse are squirrels -- think nuclear-powered mice on steroids...
So, don't worry about the effect of slowly lowering and rising temperature on pianos but consider other environmental factors.
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Keith Akins
Akins Pianocraft
Menominee MI
715-775-0022
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Original Message:
Sent: 11-15-2021 10:48
From: Timothy Edwards
Subject: Freezing pianos
I have a customer with a 7' Young Chang who is inquiring regarding the effects of leaving the piano in a house with NO heat during the winter. Located in Oklahoma. The only effects I can think of would be the possibility of condensation on the action centers and keypins. causing sluggish or sticking action. What else should be considered?
What remedies or precautions might I suggest?
As always, thanks for all the great advice.
--- Tim
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Timothy Edwards
Beckley WV
740-517-7636
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