>My 71 semi-camperized bus has, among other accessories installed by an
>unknown PO, a unit called a Pla-Cool that sticks up out of the otherwise
>stock roof. It's a white, rounded, heavy-duty plastic sort of cowling
>affair, about 6" tall and maybe a foot square. I think it might be a
>circulating water air-cooler, but I really have no clue.
>
>Controls are mounted on the bottom half of the unit, which protrudes
>downwards from the bus ceiling. It has on/off switches for "fan" and "pump"
>and another switch that flips it from "cool" to "exhaust."
>
>It sat unused for years until one day I noticed, tucked back in right rear
>corner of the engine compt. above the battery, an empty fuse holder. I
>popped a 15 amp fuse in, went into the bus and turned the Pla-Cool on, and
>the fan began to whirr. Paranoid of a possible VW electrical debacle, I
>turned it off, took the fuse out and haven't touched it since.
>
>But I'm curious. Anyone have experience with these things? Does it 
circulate
>water (that intriguing "pump" switch)? If so, where do you put the water 
in?
>What amp fuse should it take? Would I be inviting disaster to use it?

Sounds like a swamp cooler. My mobile home in Colorado had one, a lot
bigger than yours of course. It has water in a trough at the bottom,
and a pump to spray the water onto a porous, fibrous material, and a fan
to draw outside air in, through the wet porous material and into the
mobile home. This evaporated the water and cooled the air. A nifty idea,
and very powerful.

Never seen one on a bus, tho I've heard of them. Sorry I can't help with
electrical details. Any manufacturer name and/or address and/or number?

You might also ask at an RV shop-- they may also be familiar with them.
                          ,
                         / \          JL
                        /   \         TT        Steve Maher
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