Condensation build up in indoor sign cabinet

[Pixels Are Bad Mmmkay?]

We ordered a 12" x 48" hanging lighted sign cabinet for a customer a little over a month ago. We put a graphic on the polycarbonate diffuser panel, delivered, and installed it in the customers front window. The sign hangs a couple inches behind the front window which, if I remember correctly, is a newer double pane window. The customer is happy with the sign but is complaining that the sign panel is collecting condensation inside the cabinet. It's enough that if you tap the panel the condensation will run down the panel. The fixture uses two 48" T5 flourescent bulbs and has a small vent hole on one end of the cabinet.

So my question is, what options do we have to help her with this issue? Should she check the humidity in her office and buy a dehumidifier if neccessary? Or could I wire in a 110v PC fan to circulate air through the cabinet, if they even make 110v PC fans small enough (would have to be two inches or smaller in diameter)? Any thoughts or suggestions on this? Thanks for any input.

 

[Billct2]

How about just adding a few vents top & bottom? You can use the round type from the hardware store & a hole drill.

 

[Pixels Are Bad Mmmkay?]

I just wonder if extra vent holes in the cabinet would be enough. I don't want to go chopping into her cabinet if the end result is less than acceptable, hence the reason I figured a PC fan may give it the additional airflow it needs, although it may also add noise.

In my opinion, I'm guessing a dehumidifier would be all she needs, but without knowing how much moisture is in the air, it's hard to say if that's the sole culprit.

 

[J Hill Designs]

I would also go the route of adding some louvered vents. they come fairly small and will offer quite a bit of air flow

http://www.homedepot.com/Heating-Ve...&storeId=10051&catalogId=10053&searchNav=true

 

[Gino]

That doesn't sound right. Besides, if moisture is collecting and running out, it could also be running into sockets or under raceways. You could be liable for a malfunctioning back-lit cabinet, should anything go wrong. Mini-fans and dehumidifiers are not your answer. They might solve a symptom, but it isn't going to rid the problem.

Is the box U/L approved/stamped ??

 

[Marlene]

does the front window also fog up or only the sign?

 

[Techman]

I would be looking for the source of the water.

That's a lot of water. But, if the face is close to a cold window that cold could be transferring to the panel and could be causing the water to condense.

Move that hanging sign farther away from the window would likely be a good resolution.

 

[MikePro]

we've had issues like this, in the past, with our exterior letter-change cabinets.
couple of vents and, in extreme cases (like yours), we even added a computer fan (ties right in to the LED power supply) to help circulate the air even more.

 

[Pixels Are Bad Mmmkay?]

does the front window also fog up or only the sign?

Just the lighted panel fogs up. There is no sign of excess humidity by way of the windows on the building so I'm a little bit miffed by it.

 

[Pixels Are Bad Mmmkay?]

That doesn't sound right. Besides, if moisture is collecting and running out, it could also be running into sockets or under raceways. You could be liable for a malfunctioning back-lit cabinet, should anything go wrong. Mini-fans and dehumidifiers are not your answer. They might solve a symptom, but it isn't going to rid the problem.

Is the box U/L approved/stamped ??

You know, I'm actually not sure. It's been over a month since we purchased it. I will be looking into that, since I'm unsure at this point.

 

[Pixels Are Bad Mmmkay?]

Gino,

According to the company website, their signs are built to meet or exceed UL specifications. Does that necessarily mean they are a UL listed company? I would think quite possibly not. But at least they say they build their signs to meet or exceed those standards, so who knows?

 

[Moze]

You should be fine just venting it. Illuminated signs are hung directly against/next to exterior windows all of the time and don't have an issue with condensation forming. Put a couple of vents in it and let it breathe and see if it fixes the problem.

 

[Gino]

Gino,

According to the company website, their signs are built to meet or exceed UL specifications. Does that necessarily mean they are a UL listed company? I would think quite possibly not. But at least they say they build their signs to meet or exceed those standards, so who knows?

Doesn't matter what their website says, indicates or suggests. The whole thing is if it's built to U/L standards, it should not be sweating as your client is suggesting with moisture actually running out of it. If it's stamped U/L, I'd call the company and demand they exchange it before a fire or something else starts and you're found guilty of delivering faulty goods.

Regardless of what the others are telling you how to possibly vent your problem, you need to have that thing checked and make sure something somehow is not overheating for some odd reason.

For the little bit of heat build up in an interior cabinet to cause that much water means something is very possibly wrong. It could be as small as a heat vent down below or the customer is exaggerating, but you being the supplier and installer needs to have it 100% correct. Your name is all over that thing and you'd be the first party and probably the only party named on a lawsuit should something go wrong. If you bought faulty fixtures, they [where you bought it] won't be held liable as you didn't make sure an electrical item you bought for someone else is actually safe by this country's standards. You only read their website.

So again, is it stamped ??
​

If not, I'd take it down, get another one from someone reputable and then dissect the old one and find out if you needed to be scared or not. One thing to consider, I am giving you the worst case scenario. It could be just fine, but when it comes to electric signs, lives can easily be lost, so this is not an area I take too lightly.

The very least you could do is to take it down and test it in a window in your own shop or house. Try to duplicate the conditions and see for yourself.

 

[John L]

What kind of business is it? If it's a hair salon, dry cleaners, pet store, or if there is a shower or dish washing going on, steam heat, an HVAC humidifier, recently had carpets cleaned, etc. then this is expected... otherwise, no. I'd ask where the hot water is being used? Sounds like it is just condensing near the cold storefront glass possibly.

 

[GVP]

What about a few little bags of desiccant - silica gell?

 

[Doc Savage]

Doesn't matter what their website says, indicates or suggests. The whole thing is if it's built to U/L standards, it should not be sweating as your client is suggesting with moisture actually running out of it. If it's stamped U/L, I'd call the company and demand they exchange it before a fire or something else starts and you're found guilty of delivering faulty goods.

Regardless of what the others are telling you how to possibly vent your problem, you need to have that thing checked and make sure something somehow is not overheating for some odd reason.

For the little bit of heat build up in an interior cabinet to cause that much water means something is very possibly wrong. It could be as small as a heat vent down below or the customer is exaggerating, but you being the supplier and installer needs to have it 100% correct. Your name is all over that thing and you'd be the first party and probably the only party named on a lawsuit should something go wrong. If you bought faulty fixtures, they [where you bought it] won't be held liable as you didn't make sure an electrical item you bought for someone else is actually safe by this country's standards. You only read their website.

So again, is it stamped ??
​

If not, I'd take it down, get another one from someone reputable and then dissect the old one and find out if you needed to be scared or not. One thing to consider, I am giving you the worst case scenario. It could be just fine, but when it comes to electric signs, lives can easily be lost, so this is not an area I take too lightly.

The very least you could do is to take it down and test it in a window in your own shop or house. Try to duplicate the conditions and see for yourself.

I agree. We just went through rounds of issues with Sloan LED lighting at our shop. Sloan claims the lights meet IP68 specs but we are having issues with water damage to the LED modules from condensation under certain circumstances.

 

[Gino]

I agree. We just went through rounds of issues with Sloan LED lighting at our shop. Sloan claims the lights meet IP68 specs but we are having issues with water damage to the LED modules from condensation under certain circumstances.

Are you LED's inside in a can or outside in a can ??

The OP's problem is with an interior cabinet..... and a small one. Inside, under.....for the most part, a rather controlled environment. I don't know how under normal ccircumstances this could be happening, unless something is wired wrong or some outside source is greatly contributing to create this problem.

 

[Techman]

ya, like being up against a ice cold window thus transfer cold to the panel face where water Will condense just as it will on any cold surface in winter. All the temperature on that panel has to do is get down around the dew pint and the water will condense out of the air..

 

[signage]

Gino could you tell me how a sign being "wire wrong" can cause moisture?

 

[ThinkRight]

We ordered a 12" x 48" hanging lighted sign cabinet for a customer a little over a month ago. We put a graphic on the polycarbonate diffuser panel, delivered, and installed it in the customers front window. The sign hangs a couple inches behind the front window which, if I remember correctly, is a newer double pane window. The customer is happy with the sign but is complaining that the sign panel is collecting condensation inside the cabinet. It's enough that if you tap the panel the condensation will run down the panel. The fixture uses two 48" T5 flourescent bulbs and has a small vent hole on one end of the cabinet.

So my question is, what options do we have to help her with this issue? Should she check the humidity in her office and buy a dehumidifier if neccessary? Or could I wire in a 110v PC fan to circulate air through the cabinet, if they even make 110v PC fans small enough (would have to be two inches or smaller in diameter)? Any thoughts or suggestions on this? Thanks for any input.

Just a hack here .... but sounds like an easy fix.
Windows in a building are referred to as heat load.
( look and see all your a/c vents at windows)
You set your sign in the air path of the A/C , and when 55 -60 degree air hits that vented cabinet , it condenses all the moisture in the air.
Move the A/C vent or the sign.
Remember that when you move the vent , it will change airflow in the room and it will work differently .
Instead of more vents , insulate the sign somehow.Or make the the signs air tight. But still you have to remove heat somehow. (heat sinks ?) Right now it is basically a dehumidifier.
The A/ C vent is there for a reason , comfort .
Hope this helps.

 

[Gino]

Gino could you tell me how a sign being "wire wrong" can cause moisture?

You're the electrician on this site. I'm sure you already know. So, perhaps you can enlighten the rest.