I recently acquired rechargeable Phonak Marvel 90s, my first hearing aids. As I live in central Italy where summer temperatures are in the mid thirties Celsius I thought it might be prudent to buy an ultra violet drying box. The problem is that I would have to get up in the middle of the night to transfer them from the box to the chargers, or settle for their being unavailable for several hours in the evening while they were in the box or being charged. Searching the net, the only dryer I found specifically made for rechargeables was Flow-Med’s Dry Box. Unfortunately it only seems to be on sale to audiologists. I’d be very grateful for any solutions the community might offer.
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Ahh the quandary. Recharge your batteries but give up drying them in a proper HA powered dehumidifier. Everyone knows moisture is not a HA’s best friend yet HA manufactures have looked the other way while pushing rechargeable battery kits with “no” drying element. You might be able to find a few battery chargers that accept a desiccant capsules but that’s not an ideal solution to drying out HA’s over night. In fact its old technology that doesn’t hold a candle to powered HA dehumidifiers.
You will see a lot of future HA users looking closely at Widex come end of year since Widex is coming out with cell “charging” technology that get the HA charged in 30 seconds of less. Once HA is charged at night then you can transfer it to a proper dehumidifier that will dry out your Widex aids for next days use.
Bottom line - HA’s will perform better and last longer if they are property dried out at night, especially during hot summer months when humidify is very high.
The dryers are just flat good maintenance for hearing aids. When the rechargeable hearing aids came out I was ready to jump on board until I remembered having itchy ears all the time before using a dryer/sanitizer.
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I believe these Marvel hearing aids come in models which use a 312 or 13 size battery. Is it too late to take them back and exchange them for a model that uses a replaceable size 312 or 13 battery? I suspect there may be a cost reduction, as well as a gain in user convenience.
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If they let you exchange the Mavel’s For the battery type get the size 13 as they last you up to 2-3 weeks. The 213 only last 7 days. Then ask for a D-Dry box as well, good luck in your exchanging your marvels.
The Marvel’s charger has a space for a desiccant tab (it fits in the round area on the top half of charger box). You can order these from Phonak or your audiologist. Some people will place one of the small dessiant packs that come in pharmaceuticals in there as another option. . .I don’t think you will really need the dehydrator box if you take advantage of this space in your charger. . .
Chris
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Many thanks for replying. A helpful suggestion but unfortunately no longer an option
Thanks for replying. Unfortunately my Marvels were supplied with the mini charger. I am reluctant to buy the charger you refer to which takes tablets as I gather they’re less effective than using UV and the charger itself costs more than double the price of an ultraviolet box.
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Rechargeable Phonak’s are $100 more each. I have new replaceable 70 with 13 battery. Batteries are good for 2 weeks which includes streaming. I’m considering going with the rechargeable. I’m still within the trial period, I just have to pay the $200.
I wonder if the mini-charger would fit in one of the UV/dryer boxes along with your aids? A small hole with a sealing grommet for the power wire to come in. Problem solved…
I just went through a similar thought process. As it turns out, my HAs (Rexton Adore) come with a charger that has a drying function. Not that this fact was particularly front and center; I stumbled upon it deep into the manual.
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I don’t have HA’s with rechargeable batteries, and for various reasons I would not buy them. That said, it seems to me that if the rechargeable batteries stay inside the HA body when they are being recharged there will be enough waste heat generated to warm them up and dry them out, providing there is reasonable ventilation to get rid of the warm humid air generated. In other words if the recharging system is well designed there may not be any need for anything more.
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Not sure that the dose and duration of heat is sufficient given that there are few chargers that are specifically designated as drying also. I am aware of only my charger that is so described.
If any charger could also dry, I doubt that manufacturers could resist the opportunity to add drying to their list of “features”.
My dryer only runs for 20 minutes or so. I usually use it while showering.
Not to sound too cynical, but it’s really to the HA manufacturer’s benefit if hearing aids DON’T last as long as possible, so I doubt if drying them out is a priority with them.
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This is not true. Maybe true for a mild to moderate loss. This entirely depends on Bluetooth usage and, in my case, the amount of power required by the receiver for one’s hearing loss prescription. My 13-T Marvels only last me 5 days with ultra power receivers.
What’s the humidity like under these conditions? If you look up a Mollier diagram (there’s an Android app called that, too), you will find that at any humidity up to 83% there will be “much evaporation” and from 83% to 97% humidity, there will be normal evaporation at a dry bulb temperature of 32.4 deg C or above. At any humidity below about 68% with temps in the mid 30’s C, you will have “Very Much Evaporation.” So you’re essentially living in a big dry box in central Italy. Drying your HA’s out just by sitting out will ~prevent microbial growth outside your ears. Since you’re not sterilizing the inside of your ears, when you put the HA’s back in, there will still be the same microbial fauna there that there was in your ears yesterday. The most important thing is probably just to use the same degree of cleanliness with your HA’s that you would use preparing your food, e.g., wash your hands before handling, work on a clean, new piece of paper towel or a clean cloth, etc.
Can anyone quote chapter and verse from an OEM HA manual on the need to dry HA’s in a dryer or sterilize them with UV (or by any other means)? My ReSound Quattro manual has no such instructions other than not to expose the HA’s to liquids or humidity over 90% - and it even mentions exposure to direct sunlight (UV) can lead to degradation of the plastic components in the HA’s.
Instructions for Quattro Maintenance (p.34 of RIE961 manual)
- Keep your hearing aids dry and clean.
- Wipe the hearing aids with a soft cloth after use to remove grease or moisture.
- Do not wear your hearing aids when putting on cosmetics, perfume, aftershave, hairspray, suntan  lotion etc. These might discolour the hearing aid or get into the hearing aid causing damage.
- Do not immerse your hearing aid in any liquid.
- Keep your hearing aids away from excessive heat and direct sunlight. The heat may deform the shell, damage the electronics and deteriorate the surfaces. (emphasis mine)
- Do not swim, shower or steam bathe while wearing your hearing aids.
(note for list item 5-rechargeables might be more sensitive to the heat exposure component than disposables)
Every morning any wax that was on my molds when I removed them the night before is always very dry-I don’t use a dryer or a sterilizer and I wear totally occlusive molds. Letting the molds dry out overnight makes them easier to clean the next day and I don’t need a dryer to do it. Where I live in Texas, the humidity can often rise above 80% at night outside, especially in the spring and fall, but I’ve never seen the humidity go above 70% inside our house and it’s usually in the 45% to low 60-ish% humidity range. According to the Mollier diagram app, even at 16 deg C, there will be normal evaporation at 65% humidity. We heat and air condition our house very little. I should imagine that anyone who heats and air conditions their house like the typical American has an even drier indoors and even less need for a special dryer since they’re living inside a big dry box called the American house (unless you deliberately rehumidify the air as some do).
@jim_lewis Agree with almost everything you said and certainly the main thrust of it. However you lost me a bit about letting your hearing aids dry overnight preventing bacterial growth. Source? It’s not that I think bacterial growth is a big issue, but I’m skeptical that there’s any evidence that letting hearing aids dry out is enough to stop it. I would think earwax, even “dry” could be adequate growth media for some bacteria. But to your main point, I agree that people worry way to much about drying their hearing aids.
Here’s a Wikipedia article on drying to either inhibit or kill microbes (inhibiting, i.e., “preventing,” in food preparation and “killing” in dealing with sewage sludge): (life depends on water) - some bacteria can enter into a spore state on drying but since that’s a dormant state, one is certainly inhibiting further growth by drying such bacteria)
Edit_Update: The following info about “water activity” in foods vs. microbial growth is interesting. The second table shows how dry, in terms of water activity, something has to be to inhibit various types of microorganisms. Perhaps we could consider fresh ear wax to have the approximate fat/moisture content of peanut butter. But at any rate, the table shows that something does not have to be completely dry to inhibit most bacterial growth. It only needs to have its water activity sufficiently reduced.
http://www.foodsafetysite.com/educators/competencies/general/bacteria/bac5.html
Further_Edit_Update: Don’t know how sound any of the studies are but here’s the Wikipedia take on any possible antimicrobial properties of earwax:
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I’ll buy that “drying” reduces bacterial growth, but I’m not convinced that overnight drying is enough to do it. It may be, but I think overstating claims lessens overall credibility (my bias)
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