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Hello folks - I'm new here. Long time player but first time owner of a piano. I purchased a 1918 Steinway & Sons 5'10" Model O piano that I have in my home. It's an older home from the 1930s so we don't have central air. I have been running a dehumidifier around the clock to keep the conditions at around 40% humidity. This is fine but it's quite noisy. My top priority is to keep the piano in good condition so it is still in good shape when my daughter inherits it some day.

Questions for piano owners who keep their piano at home -
-Do you have central air/humidity control?
-Do you use a dehumidifer? If so, what brand/model?
-Dampp Chasers/Piano Life Savers ? (I've been told not to go this route as it only monitors the humidity of part of the piano)

Looking for feedback from people who keep their piano at home and how they maintain it over a long period of time. For reference, I am in the US northeast, so humidity can be rough.

Thank you in advance!

When I lived in central Texas:
Central HVAC + a bit of room humidifier use in winter to keep the RH no lower than 40%.

Western Wisconsin (where winter was 5 months of the year):
In-wall A/C, baseboard heat + a room humidifier to keep the RH > 35% + a full Dampp Chaser and undercover, keeping piano closed and covered when not in use.

Southeastern US, on a lake:
Central HVAC + a dehumidifier downstairs (it's a fairly open concept home) to keep the RH < 60% on the main floor of the house.

We live in the SF Bay Area. Inside the house is normally in the 40% to 55% humidity range. Have never made any special efforts to control the humidity.

From what I understand about the Dampp Chaser system, it only controls the humidity inside the piano. If so, then the soundboard can experience a large humidity difference between its two sides. That could lead to large humidity-induced stresses across the soundboard.

In the OP's case, the need is to keep humidity from going too high. The Dampp Chaser is fine for this, as in that case it works by applying some warmth, and the heat passes through the soundboard easily enough.

In other cases where the room humidity is low and a humidifier is needed, I agree that one would need to be careful to ensure it is kept consistent outside and inside the piano.

I am in London (England). Not many houses have central a/c here - we tend to have hot-water central heating, with radiators.

At this time of year the RH indoors can be 60 or even 65% - in spring and summer it is typically around 50%. The problem time comes in winter, when in clear frosty weather the indoors RH can drop to 35% (when the central heating is on).

I aim to keep the piano room at a constant 50%, +/- a couple of %. My principal means of achieving this is a Meaco 20L Low-Energy dehumidifier. It has a sophisticated control system which achieves close control of the RH. I feel that reducing the RH at this time of year is important. This is the most satisfactory of the dehumidifiers I have had. My previous ones were de Longhi models, they both broke after three years or so. The Meaco seems very reliable, and I am impressed by the company - it is easy to get excellent technical advice from them on the phone if necessary.

On dry days in winter when the RH threatens to fall below 50, I turn down the radiators in the piano room. (Lower temperature implies higher RH.) On very cold frosty evenings I turn the heating in the piano room (and of course the dehumidifier) off altogether. By this means I successfully keep a close control of RH.

In years past when the piano room was also a living room (and so had to be at a reasonable temperature!), we used a humidifier in winter to keep up the RH - a Turmix Hygromatic 701. This has a reservoir of water which feeds a heating chamber which generates steam when required. This is extremely efficient and satisfactory, requires minimal maintenance and causes no white dust.

I chose 50% as the RH level for my piano room because (1) that was recommended for my elderly Bluthner, (2) it is achievable with a dehumidifier and occasional turning down the heating as I have described. I can imagine that with your 40%, your dehumidifier will have to work harder than mine. I am curious what you will do on cold winter nights, if the RH falls below 40%. You have the options of letting it do so; or turning down the temperature, like me; or getting a humidifier.

And by the way, congratulations on your Steinway - sounds nice. And welcome to PW!

The ideal humidity is 45%, but the acceptable range is 40-70%, so you may have to compromise. Here in Chicago I keep the humidity 50-55% in the summer and 40-45% in the winter. The seasons in between often require a humidifier one day and a dehumidifier the next, so I have a programmable controller that turns on whichever one is required. In the winter I can't keep the house above 40-45% because I'll get condensation on windows and some walls. I would guess you'll have the same problem if you have an old house. In the summer I'd have to run a dehumidifier almost all the time to maintain 45% so I compromise and let it drift up to 50-55% for those 4-5 months. Then I don't have to listen to it run constantly. You'll need to find an acceptable range that works in your house and climate.

You have my sympathy! I hate how noisy free standing dehumidifiers are!

Would it be possible for you to install something like a mini split in your piano room only?

BTW where are you located? TD mentioned Texas, is Peabody in TX? (Somehow I can't get my head around being in TX without no central air...)

With the undercover (recommended as part of a system install), it sort of creates a cocoon effect where the humidity control does permeate both sides of the soundboard. [note: I kept my pianos completely closed when not in use, which may have helped as well. I concurrently measured RH on both sides of the soundboard with and without the undercover in place and noted a difference] When I was in Wisconsin, in a building where RH levels were anywhere from 20-80% annually and outside temperatures got down to -25 Fahrenheit, I feel these systems were a big help in keeping things from completely falling apart.

If you're running a dehumidifier around the clock to stay at 40%, try setting to 50 or 55% instead, to see if you can achieve an outcome that isn't running constantly, or so noisy/expensive to run in the summertime.

I do that as well. Lid, music desk, fall board, everything is closed up unless I'm playing. I do suspect it makes a difference. Besides helping keep out dust more!

In the winter he will probably have to add humidity if he lives in the northeast.

To me it seems unlikely that will be a real problem as absorption and release of moisture between air and wood is a relatively slow process and I think actually slower than the equalisation of moisture content through the wood so there isn't likely to be a huge moisture gradient in the wood from one side to the other.

But that's just my logic, is there actually any evidence that there is a problem in the real world?

As many europeans on this forum, I have no problem with excess humidity, but serious concerns with excess dryness in winter when the central heating is on. It is particularly dangerous to harpsichords that have a much thinner and fragile soundboard, prone to cracks.

Personally I would never install any gear attached to my instruments : I would be too worried with spurious vibrations and resonances, so I have researched floor-standing room models. I used the VENTA with success, it is by far the most common device used by piano owners in Germany, although it is marketed as a personal health air washer product. It was unofficially recommended to me by Steinway in Hamburg. It is cheap and useful, but requires constant re-filling and cleaning.

I eventually purchased a Condair Defensor PH 28 It has an outstanding reputation, and is made in Switzerland by the company that takes care of Mona Lisa in the Louvre. So far I am very happy with it.

Thanks everyone for the feedback! I see there are challenges that vary by region and I had no idea humidity could get so complicated. Perhaps 40% all year round is unreasonable. I would hate to get any vibration from a sample chaser so I think I will leave that alone.

I live in Peabody, mass. It's been very humid his year and every year from what I hear from people who have lived here for a long time. I could live with a dehumidifier if I have to, but what's frustrating is the RH shown on the unit and 3 units all show different numbers. The one that I believe the most that was calibrated by professional I had cleaning out some molds for my basement due to water damage has been reading low thirties now that the temperatures have been dropping, so I'm a little concerned that I already need a humidifier. It sounds like finding an acceptable range in keeping a constant is more important than worrying about dropping below specific number or above.

It is said that wood absorbes humidity faster than it dries out. It will surely affect the tuning and if too dry for long periods of time it might cause other issues too. But, IMO, in the short term, temperature affects the tuning more readily. Especially for the longest plain strings just before the bass bridge.
I don't think mid thirties is that bad if stays relatively stable.

You will find it common for hygrometers to be very inaccurate in the range needed for pianos. There have been several threads on this forum about doing the calibration yourself, that's the only way I would believe any device. The person who cleaned your basement was probably only concerned that the RH be sufficiently below 60% to prevent further mold growth, it's possible they lacked the same interest in precision that you do. The short version is you need to calibrate your device(s) with potassium carbonate which maintains a RH of 43%, right in the sweet spot for pianos. Once you do that you will be able to figure out what RH you actually have.

I have a 1917 Steinway "O" in my home, with a complete Dampp-Chaser system installed, including the undercover. I keep the lid entirely closed when not using the piano. The tuning is extremely stable, and does not appear to be affected by the seasonal swings in humidity. I live in central New York State, where the climate is quite similar to where you are...very dry in the winter, and summers that can be perfect one day, unbearably humid the next, and dry the next (kind of like this summer). My house is old, with no central air conditioning, and forced hot air from registers in the winter. I do run a small room humidifier in the winter. The undercover was installed at least 15 years ago, and that made all the difference with tuning stability. It was like night and day once that was installed.

Thanks for that. I keep being told by the piano engineer at the shop where I bought piano that piano chasers are a lot of maintenance and they don't account for humidity swings of other parts of the piano like the keys. It is good to know that someone with an antique has made it work without running a dehumidifier. Are you monitoring humidity? What is the range you are staying within? Otherwise did you use "piano life saver" or a different brand?

Piano Life Saver is by Dampp Chaser Corporation.

Instead of trying to pinpoint the exact RH number, I would keep an eye on the significant swings in % from a season to season, and aim to stabilize it within your climate.

Piano life saver is just a combination of humidifier and de-humidifier with a controller to switch one of these one or off as needed. You can build such a setup yourself with higher capability components but, as far as I know, the life saver is the only ready made solution on the market specifically for pianos.