We installed a NEMA 3R disconnect switch outside next to an existing switchboard with overhead conduits. The new disconnet switch has not be energized. The existing switchboard is hot. We found out that there are a lot of condensate water dripping in the disconnect switch from conduit because hot air from the existing switchboard meet with cold air from disconnect switch then generate condensation water. Have you guys seen this problem before? How did you guys resolve this issue? Thanks.
condensate water in conduit and disconnect switch
- Thread starter dahualin
- Start date
- Status
- Location
- Logan, Utah
Seal the conduit passing between the disconnect and the switchboard with duct seal or other material to keep the warm air from passing through the conduit.
Chris
Chris
winnie
Senior Member
- Location
- Springfield, MA, USA
- Occupation
- Electric motor research
Mixing hot air and cold air does not in and of itself cause condensation. The moisture has to actually come from somewhere.
In the situation that you describe, you have an enclosure that is warm because it contains energized equipment and a cold enclosure. This will pump moisture from the warm enclosure as condensation in the cold enclosure. However this condensation will stop as soon as you've used up the moisture in the warm enclosure. If the condensation persists, then there has to be a source of water in the warm enclosure.
Duct seal will stop the immediate problem, however I'd suggest searching out the actual source of the water in the first place.
-Jon
In the situation that you describe, you have an enclosure that is warm because it contains energized equipment and a cold enclosure. This will pump moisture from the warm enclosure as condensation in the cold enclosure. However this condensation will stop as soon as you've used up the moisture in the warm enclosure. If the condensation persists, then there has to be a source of water in the warm enclosure.
Duct seal will stop the immediate problem, however I'd suggest searching out the actual source of the water in the first place.
-Jon
- Location
- San Francisco Bay Area, CA, USA
- Occupation
- Electrical Engineer
Maybe not in Portland (or anywhere on the West Coast), but when I lived in Florida for a time, I had to use a dehumidifier in my bedroom just to make it livable (I was born on the West Coast). That thing would suck about 2 gallons of water out of thin air every night, it never stopped.
Pierre C Belarge
Senior Member
- Location
- Westchester County, New York
Depending on the arrangement of the conduit, stuffing the end of the conduit run may not be sufficient. This is also why the NEC says that raceways shall be arranged to drain.
The OP may have to figure a way to drain the conduit as well as stuff the end with duct seal.
The OP may have to figure a way to drain the conduit as well as stuff the end with duct seal.
TxEngr
Senior Member
- Location
- North Florida
I'm assuming from your description that the conduit is top entry into the disconnect. Move the conduit to bottom entry and place a low point drain on the Tee where you turn from vertical to go into the disconnect. This will elimininate much of the problem. Finally, there is a company that makes a product you can place in the bottom of cabinets that will absorb moisture. I can't recall the name but it will soak up something like 20X it's own volume in water. I used it a number of years ago on a cabinet that had a similar problem.
TxEngr
TxEngr
plumb bob
Member
- Status