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Steam possibly causing problems?

Barry_E | Posted in General Questions on

I have leased out a building that is used as a micro brewery. They use what was the restaurants kitchen for the brew area. The building was built in 2014. It is a steel building with the kitchen being framed inside, metal studs but the ceiling in the kitchen has wood ceiling joists with an area above for the heat/ac duct work,,,,. There are six t8 fluorescent light fixtures with six, 4′ bulbs in each. There are 4 vents for the duct work also coming through the ceiling, all of this is directly above the brew tanks. Ceilings are 10′, just a guess I didn’t measure this. 

I recieved a call yesterday from the fellow who’s brews the beer and he said one of the light fixtures would not work with any new bulbs, so we’re thinking the ballast is bad. When I arrive the front doors which are not in the same room are covered in moisture. There’s some moisture on another door and windows 30′ away from the front, all the doors are full glass. We go into the brew area and the lid is open on one of the large tanks and steam is boiling out but not visually getting things wet above it. The light that is out is directly above the other tank that was the first to be installed.

I don’t know if the Sheetrock on the ceiling is the moisture proof kind or regular, I’m not sure what code would call for in a commercial kitchen? There is the commercial exhaust system but it sucks all the heat out of the room in winter. 

I think it’s possible the moisture may be the problem with the light and it may be causing other problems that haven’t shown up yet. Should there be something like a bathroom exhaust fan above these tanks to take care of the moisture?

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  1. Expert Member
    BILL WICHERS | | #1

    I would suspect the moisture is causing the problems. That open tank of boiling water is acting as a big steam humidifier. Assuming that runs all the time, you’re putting a LOT of extra moisture into the air. If an exhaust fan is a problem with heat loss, you need some kind of industrial size HRV.

    I’m not sure if it will work for a brew setup, but it’s common in industrial plating baths and other things needing to retain heat, to use polyethylene spheres (balls) floating on top as an insulation layer. You can get these from industrial plastic suppliers like US Plastics in Lima Ohio. They’d be able to tell you if the plastic spheres had the required NSF ratings for food use, but I bet they do. These balls will help retain heat and will also reduce the rate of evaporation in the tank by reducing the total air/water interface area.

    Those lights are probably having issues with condensation. I’d recommend using exterior rated fixtures intended for use in wet environments. These fixtures will be sealed and will last a lot longer before having problems. Make sure they are far enough above the tanks that they don’t get too hot as well. This would be a good time to replace those T8 fixtures with LED fixtures too!


    1. ssnellings | | #4

      Another common term used for lighting that would be appropriate for this environment is 'washdown' lighting. Lighting rated for UL 'wet' or 'damp' would be appropriate. RAB Lighting sells a few models of LED strip lights rated for these kinds of environments, just to give you a manufacturer to start with.

      Getting a handle on what the humidity is like in that room will be important for figuring out how to mitigate - the glass condensation is a good clue that something will need to change. I don't have a good recommendation on inexpensive logging equipment, hopefully someone else will chime in with more experience.

  2. MattJF | | #2

    Moisture is very much a concern with what you describe.

    Exhaust and makeup air is critical. Is there any existing exhaust equipment?

  3. Barry_E | | #3

    There is a commercial hood/exhaust system right next to the tanks but is much lower in height. I’ll get a photo so you have a better idea. Thanks

  4. Barry_E | | #5

    (((I’ll go by and take some photos with the camera turned so it’s easier to understand))).

    When I went by yesterday there was condensation on the inside glass (a day after he brewed) . The photo of the door the moisture is on the inside. You can see the larger exhaust that was used for cooking but not moisture.

  5. walta100 | | #6

    What is the indoor temp and humidity and how cold can it get outdoors. Given the right conditions a lot of mold could be growing behind the walls.

    To my eye the light fixtures do not do not look like they would carry a NSF label or even be rated for use in a damp location. It seems to me that a brewery would be doing “food processing” and all lighting and plumbing fixtures should be require to have a NSF label.

    If I owned the building I would require the tenant to install and maintain whatever equipment is necessary to keep the indoor dew point 5° above the current outdoor temp.

    I know getting valid building insurance for a distillery is difficult Was it hard getting a policy for a brewery?


  6. Expert Member
    BILL WICHERS | | #7

    I don’t know why the lights would need NSF approval. NSF usually only tests things that would actually come in contact with food products, things like pots, tanks, piping, that sort of thing. Lighting shouldn’t normally be in contact with things you’ll eat or drink, so wouldn’t normally need NSF testing.


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