I have a cheap, Taiwanese-made aluminum outdoor CCTV security camera enclosure that I bought years ago (I don't even remember where I got it - maybe at a ham radio flea market). Based on what is printed on the outside of the cardboard box, the enclosure is supposed to support an internal heater/blower fan, including a sensor to turn them on and off, however no heater, blower, or sensor was included in the box.

How are those supposed to work? The enclosure has no (visible) air vents, so it does not appear to be designed to exchange the inside air with the outside air. So, maybe that means that the blower just circulates air inside the enclosure (to help prevent condensation on the camera lens and enclosure window?). Evidently the fan (and heater?) is intended to be controlled by a thermostat? Or is that intended to be one thermostat for the heater and a different one for the fan (for cooling if it gets too hot?). But I'm not sure how a fan is going to cool down the enclosure if it does not have a way to exhaust the hot air and replace that with cooler air.

Here are some pix of the enclosure or similar ones, including some pix showing the printing on the outside of the cardboard box (I found these on the internet, but could not find any details about the enclosure itself - a lot of the sites that come up in the google search results are pretty sketchy, most likely they are fraudulent e-Commerce sites that republish stolen images from eBay and from other sites in an attempt to harvest credit card info from unsuspecting wanna-be buyers).




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There are some vendors who sell add-on heater/blower kits, like this one:




That particular add-on kit shows this as the separate heater and blower temperature ranges, so that implies that the heater is to warm up the enclosure and camera if the temperature drops too low, and the fan is to cool things down if the temperature rises too high, but maybe I'm misinterpreting it (15 C is 59 degrees F, 25 C is 77 degrees F, 35 C is 95 degrees F, so those don't sound like direct turn on/turn off setpoints unless what it means is something like turn heater on for 15 C or below, turn back off at 25 C or above, and reverse for the fan etc.):




And this is an image showing how a similar kit may be installed inside of a similar enclosure - the fan is at the left, the sensor is to the right of the fan, and the heater element is all the way at the right, near where the camera lens would sit:




And another cardboard box photo:

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And a picture of the bottom/mounting for the enclosure that I actually have (the one above showing the bottom is for a similar enclosure with the same box as mine):

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I have looked through the huge CCTV info thread here arfcom CCTV cameras 101 thread but unless I somehow missed it, I don't think that this topic was covered there.

So, can anyone help me understand how these things are supposed to work?

Thanks...

No answers yet.

I had considered the possibility that the two ports at the rear of the housing could function as air exchange ports, except that those are more likely intended to be used for power and signal cables (which may be combined in some cases, via power injection over the signal cable), and so those would normally be expected to be sealed up to prevent ingress of water, insects, and the like.

So I'm still looking for guidance on how heating (but more importantly, cooling) is typically done with such housings and heater/fan/thermostat assemblies such as the one that I showed above.

It seems that for much more expensive CCTV camera housings, a variety of techniques are used to handle (heating and) cooling, as well as avoiding condensation on the lens and/or the window.

Those techniques are obviously out of scope for what I'm planning, but they are interesting - everything from using dry nitrogen within a sealed housing in place of ordinary air, replaceable bags of desiccant chemicals to 'suck' moisture out of the air, hi-tech vortex coolers that use pressurized air and physics to handle cooling without exchanging air between the outside and inside of the housing, solid-state electronic "Peltier" coolers, and more.

Heaters and blowers are typically for avoiding icing or condensation on outdoor cam enclosures.  How critical they are depend on where you live.  My outdoor cams are all under eaves in sunny Silicon Valley, and there's no need for this type of thing.

The most basic, like you show, just heats the enclosure, similar to a heater reducing condensation in a gun safe.  As you found, high end gear uses more sophisticated solutions, which cost a lot more but can be necessary for high priority installations.  Cooling can be important for cams with a high power draw, like lots of IR or zoom/rotate controls, but getting the heat outside the enclosure adds more complications.

You don't generally want air exchange, because openings to the outside also let in spiders, rain, dust, etc.  These can be avoided with filters and such, but again, more expensive, and more maintenance required.

OK, thanks...

I will need to handle the potential for condensation or icing. I'm unsure of whether overheating will be as big of a concern, but I can probably run some tests - monitoring the temperature inside the enclosure will be easy enough to handle (although since it's currently early spring, I won't have an opportunity to test the extremes that I might encounter either in winter or summer).

What I'm working on is more of a hobby than a critical security application, so I can afford to do a little bit of experimentation. I will have to search through my junkbox - I might actually have a peltier device that I bought to play with a few years ago (or if not, I might spring for one from eBay).