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12V observatory Dehumidifier with drainage

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#1 Hilmi

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Posted 01 December 2012 - 05:41 AM

After finding some mild corrosion on my equipment due to humidity, I am considering installing a 12V dehumidifier like those being sold on www.optcorp.com But I can't find any mention of drainage on the container, it seems that the ones they sell require that I remove the tray and drain the water manually. With the levels of humidity I face in the summer, this won't do. So I am looking for a 12V dehumidifier that also drains down a tube so that I can keep my equipment dry in the summer. Anybody know any?

#2 Mirzam

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Posted 01 December 2012 - 08:45 AM

If you have AC service in your observatory, I think a full size dehumidifier would be needed. The small units sold by OPT might be okay for moderate humidity conditions in a well-sealed space. But I doubt they will have enough capacity for your situation.

You could also use an air-conditioning unit, which would dehumidify and cool the air.

JimC

#3 Hilmi

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Posted 01 December 2012 - 09:18 AM

Thats an extra $25 a month on the electric bill to run my aircon continuously. Need a low running cost sollution

#4 Lorence

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Posted 01 December 2012 - 02:34 PM

Thats an extra $25 a month on the electric bill to run my aircon continuously. Need a low running cost sollution


I think Jim is referring to A/C power in your observatory, not air conditioning and is suggesting that you use a line powered dehumidifier. I agree with him. The 12V will likely be inadequate, regardless of what the manufacturer says. The larger dehumidifier will have provisions for a drain hose.

Something you may want to consider is that dehumidifiers use some sort of refrigerating device to remove water from the air. In doing so they make nice little space heaters. If the dehumidifier is running quite a bit in your observatory it will warm it up significantly.

#5 Mirzam

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Posted 01 December 2012 - 06:17 PM

Actually, I was referring to air conditioning (run on AC current). Two additional aspects come to mind. The air conditioning has the benefit of helping cool the equipment to ambient nightime conditions, which may or may not be that important. If you have equipment that will cool off easily--then its not important. Also, a dehumidifier is essentially the same as a small air conditioner in terms of power consumption. I'd run it on a timer so that it only comes on when the conditions are especially bad.

Another solution might be to oil coat the things that have a tendency to corrode.

JimC

#6 piaras

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Posted 01 December 2012 - 06:48 PM

As well as a timer you could use a Dehumidifing controller.

Maybe something like this control. It requires 120 volt, is a problem if you only have 12 volt available.

http://dewstop.com/

#7 Hilmi

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Posted 02 December 2012 - 07:19 AM

I would have put the aircon on timer, unfortunately, this AC has a very primitive timer function, only how many hours before it shuts off. It's also no good putting a timer on the power socket, after power loss, on resuming power it goes on standby. That's why I was looking for another way to control humidity.

#8 evil16v

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Posted 08 December 2012 - 02:37 AM

I don't know about the e12v humidifier that you are talking about in particular... But i know most 120v household portables have a collection jug, with a capped garden hose type connection for a drain. Mine does.

#9 Hilmi

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Posted 09 December 2012 - 01:24 AM

Rob,

Thanks for the suggestion, I have been looking around in the local market and I can't seem to find a dedicated dehumidifier. It seems that due to the hot weather, everybody has an aircon unit running at home anyway, so they don't see the point in owning a dehumidifying unit. Therefore, there is no market for them in this part of the world. Can't import one from the US as its the wrong voltage.

#10 nytecam

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Posted 09 December 2012 - 06:20 AM

My condesation problems are in winter. I had a small mains dehumidifier in my Meade dome [as avatar] a decade ago but it was ineffective as the space was not sealed and effectively it tried to dry-the-universe :( Since used a small electric greenhouse heater with thermostat under the scope [when not observing!] but not entirely effective. Currently got a large but economic domestic mains fan running continuously and the constant air movement in the small obsy space seems effective - we will see :grin: But your problems in summer humidity :shocked:

#11 Hilmi

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Posted 09 December 2012 - 12:28 PM

Humidity + salty air = corrosion, you don't even need condensation for things to corrode. I have an air-con, works very well, costs too much to run continuously. A fan would stop condensation, which I have no trouble with as the temperature in the summer insider the observatory is usually above condensation temperatures.

I guess my best option would be to look for a UK dehumidifier as this would have the same voltage rating as Oman.






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