Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum Dampp-Chaser dehumidifier rods - powerful enough?

Hi Techs

I wonder, would you mind letting me know what power ratings you would recommend for the two dehumidifier rods in a Yamaha C2M grand?

...I forgot to mention that during the year, the humidity in my house varies approximately between 35% and 80%

Thanks in advance

A piano tuner will be able to provide the proper system for your piano. Dampp-Chaser have to be install by a tuner. Dampp-Chaser provides information for various piano on their web site in area reserves for techs. Call your local piano tuner and have him/her install the system for you.

Let me explain further:

I installed the Dampp-chaser in my 178cm Thürmer grand myself. More info here . Please ignore the part about wanting to become a DC installer, this no longer applies!

I'm now due to part company with the Thürmer and I'm getting a 173 cm Yamaha C2M instead. For various reasons (geographical location and otherwise) I will transfer the DC to the Yamaha myself.

My reason for asking about the dehumidifier rods is that I noticed during last summer that the RH at the humidistat location never went below 54% (+/- 2 or 3%). The RH in the room in general was mostly in the 70's but occasionally in the low 80's. Whenever I touched the heater rods (which was regularly) they were hot. Additionally, the humidifier used hardly any water other than, I guess, through evaporation. Right now in winter the RH at the humidistat is consistently in the region of 43% and I'm adding water regularly (heater rods are often cold to the touch). And so, as I suspect, are the heaters which were specified by the tech not up to the job of reducing the RH in summer to the point where the DC cycles between humidification and de-humidification, as I believe it's designed to? Also, will the fact that the Yamaha is slightly smaller than the Thürmer make a significant difference to the DC's performance?

I haven't got the rod wattages info to hand but as best I can remember the long rod is 35 W and the short rod 18W (something close to these figures anyway).

As I'll soon be transferring the equipment, I would greatly appreciate your views on what I've written.

Further info:

Due to unrelated piano buying issues, I've fallen out with the tech/salesman mentioned (the guy's crazy!) and so, I'm on my own with this.

One easy method to determine if you have enough power is to plug in an analog clock to the dehumidification side (along with the bars). Then during the humid time of the year, check to see if the clock loses time. If the bars never turn off, the system is underpowered...

You may want to consider a bottom cover and/or string cover to provide more stability.

Ron Koval

I usually use the 50 watt long(48") rods and the 38 watt short(36") rods. On grands 6' or longer I will use 2 50 watt rods and one 38 watt rod. On smaller grands I use just 1 50 watt and 1 38 watt.

Thanks for the replies

It seems as though my tech did indeed specify rods of inadequate power, especially when I see what Ryan uses in small grands. It appears that my 'long' rod is what Ryan uses as his 'short' rods!

Incidentally, I've checked the power ratings of the rods in my system. They are:

91 cm primary dehumidifier - 38W
61 cm secondary dehumidifier - 25W