Reducing Condensation

[dmxrr]

Hi,

I'm having issues with water ingress into our actuator switch box's which is causing issues. The enclosures themselves are rated to IP67 but some form upto 10mm of water In the bottom, I believe it is an issue of condensation as these actuators sit on top of high pressure air lines which while in use get up to around 50/60 degrees. Has anybody got any ideas to reduce build-up? I'm thinking maybe some 1/4" tube out of a cts gland or possibly a decent vent plug?

 

[Essex1]

Heating and ventilation. 

 

[binky]

what actuators where? Indoors, outdoors? Sounds more like leakage if they get upto 50deg C - they should dry themselves out, and if reasonably sealed up in the first place, how is damp air getting in?. Think a small drain hole might resolve your issues???

 

[NozSpark]

However.... If you add ventilation or a drain hole you will reduce the IP rating of the enclosure.

TBH if you are getting 10mm of water inside an IP67 enclosure then you need to look at whether any of the seals have perished

 

[dmxrr]

what actuators where? Indoors, outdoors? 

They are pneumatic valve actuators situated outdoors by the coast with little protection from the elements. Poor design from the off but I can't see how water is getting in to these from any other way. It should have been a warranty issue IMO as these units have been problematic from the start and are only 3yrs old.

 

[Andy™]

if they go between hot an cold often (you said there was hot pipes above), then this may be forcing air in & out, which condensates and leaves you with water

simple solution may be a small drain hole

 

[Lusk]

Is your instrument air truly dry?

It could be moisture in the actuators' exhaust condensing out.

 

[NozSpark]

Rather than reducing the IP rating of the enclosure by drilling a drain you could fit a pressure equalising seal..

Something like...

https://www.sealingdevices.com/gore-vents

 

[dmxrr]

Appreciate the replies, I think I'll try the Wiska Vent Plugs and possibly get some silica gel from RS as @Canoeboy mentioned and see where we go from there. Cheers

 

[binky]

don't see how the vent plugs will help if moisture is getting in?

 

[Davethsparky]

Drain plugs will help a lot more and maintain the IP a bit better. Can't remember the proper name of the type of drain I'm thinking of but it's commonly known as a donkey dick valve, there's one on the air filter housing of defenders

 

[dmxrr]

don't see how the vent plugs will help if moisture is getting in?

I'm just going by this http://www.wiska.com/en/products/cat/313/venting/

Drain plugs will help a lot more and maintain the IP a bit better.

Drain plugs will be ideal for some of the vertically mounted units however most are mounted on the horizontal plane and there is no suitable space/place to site a drain plug hence vent plug on these.

 

[binky]

that makes sense, but can't help fell that drilling a 1mm hole would do the same thing and allow drainage

 

[Andy™]

adding vent plug will still allow moist air in, which will still turn into condensation...

 

[dmxrr]

adding vent plug will still allow moist air in, which will still turn into condensation...

Better than nothing, that's where the silica gel comes in.

As for a drain hole, well that's not ipx7 is it?

 

[NozSpark]

Like I said you could fit these and silica gel sachets and maintain the IP rating and stop the enclosure sucking in moist air....fit them while every things cold though

Rather than reducing the IP rating of the enclosure by drilling a drain you could fit a pressure equalising seal..

Something like...

https://www.sealingdevices.com/gore-vents

 

[Andy™]

Better than nothing, that's where the silica gel comes in.

As for a drain hole, well that's not ipx7 is it?

no, but does it need to be ipx7? if its not likely to be submerged and only water it can get would be from above / sides, then a small drain hole in the bottom shouldnt be an issue

 

[NozSpark]

But a drain hole is still allowing the air in and out,,,, I would have thought that the idea would be to seal the enclosure in a way to stop any air exchange

 

[Andy™]

yes, but it gives the water a way out

 

[binky]

the enclosure clearly doesn't keep water out, a vent plug with micro-porous membrane may work, but depends on how much water vapour it will allow to penetrate??? Putting drain hole in will work same as an outdoor socket and is a lot easier. Issue is pressure equalisiation as the unit cools down, which causes a vacuum, and no doubt sucks moisture in that may be resting on the unit on damp / rainy days. A startegically located small hole will allow very quick pressure equalisation without allowing a vacuum to develop and if in a dry(ish) spot will prevent sucking water past the seals / joins of the enclosure. Got to be worth a try before buying vent plugs etc etc. Don't think I would go down the silica gel bag route personally - too much like piddling about for my liking