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Hi

Im new on this Forum and would like to ask about a heating bar that I want to install on my Yamaha upright piano.

Im makig a bar by myself using an aluminium pipe (1,2m) and two heating elements of 30W SOLDERING IRON to install in both tips of the pipe. Will receive today (i hope) a smal piece to control the power of heating elements in order to control the temperature.

Im affraid to heat the bar a lot and cause any damage to piano.
So I wolud like to ask gentleman, what is the ideal temperature of the bar?

Thanks in advance.

Roberto

The temperature is irrelevant. It is the relative humidity that matters. Unless you can accurately measure the humidity and turn the heat on and off accordingly, you will damage your piano.

What about when the humidity drops below the recommended 44%? Do you plan to have a humidifier as well?

My opinion- it would be wise to leave this one to the pros who understand such things and have done research and testing to come up with a proven system that works! Otherwise you are taking a big risk on a big ticket item (piano) regarding things that most of us, myself included, don't fully understand.

What is the seasonal relative humidity in your part of Brasil?

2 x 30 W is a lot, to me. but I heard of using simple bulb lamps installed below the bottom board, and it is not easy to get 15w or 20 w bulbs,so possibly they are 30 w too.

you will use more power with your setup than ordering one or 2 dampp chaser rods (assuming the moisture where you leave is always above 65-70%)

the only thing that matters is the moisture level within the piano (and around)

I am far from certain that under some extreme conditions , heating the piano is good (a lot, to correct high moisture levels)

I agree, but "the system that works" are not sold with precise characteristics as

what mix of temperature/humidity can be corrected by what setup of "system that works"

I am almost certain that under tropical conditions, with originally high moisture AND high temperature, the system does not work anymore, or so marginally it is not worth.

Sure if the house is climate controlled then it could be more useful.
Raising a few degrees warm humid air ?

may be better than nothing but as new air enters as soon as the warmer escapes, I don't trust that, anyway I will not without precise measures given. Today with the lower cost of moisture recorders, we should expect to have more real data of pianos under different climates.

I do know that "humidistats" are available quite cheaply in the USA.
Beyond that... I don't want to get into the discussion as to what is right/wrong, but at a guess one could wire up heaters with thermostats and humidistats in a configuration that would WORK, e.g. decide the limits you want FIRST.
I would want quite a bit of space between whatever (low wattage) heating elements and the actual "wood" of the piano, especially the soundboard.

No. Just... no.

We have to understand that in other countries like Brazil in this case, it may be impossible or cost prohibitive to get certain things that we in N. America can easily order over the phone and have delivered in two days.

While I would be concerned about trying to install a home made de-humidifier bar, I will try to answer the question about the bar temperature. I am not sure that anyone has actually measured it, but it seems that it is quite warm but not overly hot to the touch.

It is probably not more than 45 degrees C.

As has been stated, it is the humidity, not the temperature, which must be regulated. The system needs a humidistat, not a thermostat.

There are about a half dozen distributors in Brazil that handle Dampp Chaser products. My suggestion is to contact one of them and get a humidistat and dehumidifier rod. I would never recommend a rod of sufficient wattage to be installed without the humidistat.

Hi Frank,

Good to see you posting here. I hope all is well.

I have a pianist friend in Rio and he had big problems with his Steimway piano, so he now use heat bars from Damp Chaser, there is even a bar inside by the action.

You are attempting something called feed forward control.

You are trying to figure out in advance how much heat you should add to your system, and then devise a system to deliver that amount of heat.

Your idea involves a heating element and what we would call a dimmer or rheostat.

You can do the same thing with a dimmer and an incandescent light bulb.

In order to attempt this approach you need data on what your normal temperature and humidity are. Then you look at a psychrometric chart and decide what temperature you need, and calculate how much energy it will take to get there. As others have said, that may not be a small number in an area of high humidity and temperature.

That is not how the DampChaser or most of the DIY systems work. They use feed back control. They measure the humidity level and use that to adjust the input. DCs are simple bang-bang control, they turn the heater on when humidity is high and off when humidity is low. More sophisticated systems turn the heater on hotter or colder depending on just how high the humidity is.

Thank you all for the answers .

In the city where I live , São Leopoldo, South of Brazil, the humidity varies in the months from March to November , from 65% to 90 % . That to me is worrying .

The temperature ranges from 5°C in winter to almost 40ºC in summer , when the air is drier .

Forgot to mention that I live 200m from a river. So the humidity is always higher .

My idea is to put the bar , controlling the temperature so that it does not pass 50ºC or 122ºF
I'll do this with a potentiometer or dimmer. I will do several tests to arrive at the best setting .
Then I can leave the bar connected 24 hours a day . Only after that will I install the toolbar on the piano .

If my project is successful, I will improve it to also control humidity .

Let me mention that I tried to buy this bar in USA but did not succeed. As I found on Ebay , is not sent to Brazil .

I contacted the Moisture King ( http://www.kingmaker.net ) and informed me that only sell in large quantities .

I'll talk about values.
A bar 25W sent to Brazil , it would cost me somewhere around US60,00 delivered in Brasil.
Good price!

The same bar here in Brazil , it costs me about US$260.00

It's too expensive for me .

The Damp Chaser product, which controls temperature and humidity is an unworkable cost.
Import taxes here are high , which shows that we are a backward country .

To have an idea , buying all the parts separately , I spent 100.00 brazilian real, or US$ 43.00.

As you can see, the difference is large

I will continue my project and if you want, I can post my results and photos so you can see.

thank you very much

That is great, but can't you first make or buy an hygrometer. They can be found at low prices usually. You can also build one a little approximative, with 2wood planks glued crossed.

If you can keep your piano in a 60‰ moisture condition that would be great, but see, if you have (indoors) 80‰, how wariness do you need to lower the moisture, let's say to 60‰.

You will need to close the back and the largest apertures of your piano (vertical?) to get that range of corrections.
Damp chaser work fine in moderate to somewhat strong conditions, not for extreme ones, when it may just cut a little the top of the hill.
In Martinique, the bulb lamps are on all year long, or almost, without any control hygrometer that would leave them on all times anyway.

Good luck.

Hi Olek

I have this
http://www.akso.com.br/produtos/seg...grometro-digital-com-relogio-e-alarme-21

And Im buying this to put inside the piano
http://www.akso.com.br/produtos/seg...ohigrometro-digital-com-sonda-externa-22

They are very cheap. From US$20,00 to US$30,00

About the bulb lamp, a guy (technician) told me that using a bulb lamp, I would be heating only part of the piano. Protecting only part of the piano against moisture because the heat will hit not all the piano. The other part would have some kind of problem doing this. I really dont know. Thats why Im making my own bar.

Using the bar, I would be heating uniformly the whole piano.

Thanks

why not buy moisture king through a distributor? quick search and found this http://www.pianoorgandepot.com

There are SO MANY possibilities for a GOOD DIY'er.
Humidistats CAN be made at home, as kids we made crude ones with horse hair.

The heat from an incandescent light bulb could be diffused with something as simple as a tin can.

One could PROBABLY build a reasonable dehumidifier from refrigerator parts, either salvaged or new spare parts.

Tools, skills, inventiveness are the only limits

It appears you are buying measuring devices. That's much better than guessing.

But most people would buy a controlling device instead.

With a measuring device you will know what your temperature and humidity are but you can't do anything about it.

A thermostat would measure the temperature and turn your heater on when it is cold and off when it is hot.

A humidistat would measure the humidity and turn your heater on when it is humid and off when it is dry.

I do not think a thermostat or a humidistat would cost more than the meter you are buying. You would buy them from a heating and air conditioning supply store.

It probably doesn't matter because there is a good chance it needs to run all the time and will never catch up.

I cannot recommend anything electrical adapted from other appliances due to safety concerns. It could cause a fire or shock hazard.

There are mixed reviews and different opinions about the de-humidifying heater rods. I have two of the aluminum heating rods fastened underneath the soundboard of my Yamaha C7, controlled by a line-voltage humidistat (also installed under the soundboard) that I keep set on about 60%RH. The rods are energized above 60%RH and de-energized below 60%RH.

The rods are installed with insulator brackets on the wood braces below the soundboard; the rods are probably 8 inches or more from the soundboard.

I’ve been told by some technicians on PW to unplug the heating rods and leave them unplugged or remove them all together. I’ve been told by others that they do some good at keeping some of the moisture driven away from the soundboard, which aids in tuning stability. Honestly, I’m not sure whether the heating rods or good or bad.

I’ve read that a complete damp-chaser system will ruin a nice piano and I’ve read that it helps with tuning stability and longevity of the piano… I honestly don’t know which is true.

I have a small electric de-humidifier appliance/machine in my piano shop that keeps the RH around 50%. I do get tired of emptying the water basin, but it seems to keep the RH where I want it.

I’m beginning to think that acoustic pianos are not as delicate as some would lead us to believe…

Rick