Genre: Forum

When the convenience of being able to leave gear securely locked up in vans and trailers causes the odd headache. The condensation on all my gear was terrible last night as i loaded from a cold van in the a very warm and humid marquee. One of my active speakers had a fault light on for a couple of hours and a lighting fixture failed, water was dripping off it so god knows what the pcb was like. Power leads were rigid and Lamps are also replaced more often, its not too bad if you can let things acclimatise but thats not always a luxury A dehumidifier is brilliant in a van or trailer (as long as the trailer is fairly airtight). Just run it on an extension cable. Unfortunately it won't solve the cold gear coming into a warm moist venue and the resulting condensation. Never mind the humidity, it's the temperature difference that's the real problem. If you have the space in the van, get yourself one of those paraffin pancake style coldframe/greenhouse heaters. They are very safe and stupidly cheap to run. Although this will raise the humidity slightly, this is more than outweighed by the fact that the warmer air can hold on to far more moisture. That heater burning direct in the van will make a lot of moisture that'll condense onto -- and inside -- the gear. I was rather assuming the O/P was taking the gear from a warm environment (home?) to a cold one (van) and then to a warm one again (venue). If the van is pre-heated by any means at all to something near the destination temperature then there will be no condensation. Water vapor is only released from saturated air when it becomes colder. If the equipment stays sensibly at the same temperature it will not cool the air, therefore there will be no condensation. Within reasonable limits it doesn't matter how much moisture the heater generates. While the walls of an unlined van will get quite wet (being a lot colder) anything completely within the enclosure and being kept warm will be fine. Finally, the actual dew point is a combination of humidity and temperature difference. You can play games with that fact. Re: Its that time of year [Re: Folderol ] #1018619 - 14/11/12 08:11 PM Edit Reply Quote Quote Folderol: I was rather assuming the O/P was taking the gear from a warm environment (home?) to a cold one (van) and then to a warm one again (venue). I think assuming this is dangerous. Quote Folderol: If the van is pre-heated by any means at all to something near the destination temperature then there will be no condensation. In the process of preheting with a wet heat source, water will condense onto the equipment being heated. I bet the gear will inevitably be somewhat cooler than the atmosphere from the heater. And even if the gear isn't cooler than the hot gasses from the heater, there will be times when the gear does get cooler, and then the 100 percent saturated air will give up it's moisture. Including inside the gear. Quote Folderol: Water vapor is only released from saturated air when it becomes colder. Water vapour is a gas. It condenses and this makes condensation. Quote Folderol: If the equipment stays sensibly at the same temperature it will not cool the air, therefore there will be no condensation. Gear, and our environment does not stay sensibly at the same temperature! So there will be condensation. Quote Folderol: Within reasonable limits it doesn't matter how much moisture the heater generates. Sorry, I want no water anywhere around. Quote Folderol: While the walls of an unlined van will get quite wet (being a lot colder) anything completely within the enclosure and being kept warm will be fine. Sorry, can't accept that. Water coating the inside of the van will evaporate, the humidity of the air inside will be 100 percent so any (even minute) changes in temperature and air pressure will result in condensation. Quote Folderol: Finally, the actual dew point is a combination of humidity and temperature difference. You can play games with that fact. I think you are playing games! One more point... apart form the fact that the world is much more complex than just one idealised aspect of theory. Burning hydrocarbons releases not only water but carbon dioxide, which when dissolved in water forms carbonic acid. Apart form being an acid, with all that implies, carbonic acid is a conductor. And that conductor will be present in switches, ribbon connectors, potentiometers and so forth, which often have different metals in contact ... which will result in galvanic corrosion and much electronic havoc. Please, people do not use wet, acidic heat to 'solve' a problem! Keep it simple, and assume nothing! By all means warm the gear up, but with nice dry heat.