Portable swamp coolers
Posted: Fri Mar 06, 2015 7:47 am
Some time ago I found a personal swamp (evaporative) cooler at our local transfer station sitting right on top of the dumpster.
This is the unit normally found at Homely Depot:
This one looked fairly new so I took it home figuring to use it for cooling the garage during our hot summer months if it worked. I filled the 6 gallon reservoir, plugged it in and pushed the GO button. Sakes alive, the thing worked perfectly!
For the next few months I'd use it for personal comfort while running the still and running 40 or 50 gallons of water onto the ground from the condensers. After a particularly busy month, the wife commented on the jump in the water bill.
I knew I had to do something different so I grabbed an empty barrel, bought a fountain pump with a 7 foot head capability, some hose and fittings and made a barrel recirc system. That worked ok but the barrel got really hot after an extended run and I'd have to dump water on the ground to make room for fresh.
Standing in the shop doing some reloading and enjoying the blessed cool my find was putting out when I took a hard look at the still connections and inspiration hit. I dumped the recirc barrel and recovered the fountain pump, opened the swamp cooler and located all the water and electrical connections and went to work. This what resulted:
I pulled out the original dinky pump and replaced it with the submersible fountain pump leaving enough cord from the control panel and well clear of the high water level to reconnect the bigger pump with three simple connections for power. The black hose is the supply that goes to the pump.
The clear is the return from the condensers that hooks to the top of the water curtain. I used clear so I could see the flow and regulate as necessary.
The whole thing hooks to the appropriate connectors on the still column.
I refilled the reservoir, started it up and watched as the system filled the product condenser and started to circulate. I opened the needle valve to the reflux system and watched as it too filled and began to circulate along with the product condenser output. Well, at least it works without heat. Yay for me.
The next day was the acid test. I filled the boiler with a batch of feints, closed it up, fired up and started the cooler. Throttled the product condenser where I normally have it...a small stream and opened the reflux valve all the way. Once the column heated up I turned down the heat and the column temp dropped clean to 120f for equalization. I let it sit for a half an hour feeling the cooling lines. Plenty of heat coming from the reflux and into the cooler and ambient temps coming back into system. So far so good.
I turned down the reflux and began takeoff still feeling for heat in the product condenser. I set the temperature gradient and left it that way for the remainder of a four hour run checking the coolant level once an hour and the cooler worked perfectly throughout.
After shutting down I checked the reservoir one last time and found that I had only lost less than half of the capacity...less than three gallons for the entire run on a 70 degree day and at least 80 inside the garage. Not only did this work for cooling the still, it kept me cool in the garage while running.
I've got a winner!
tp (and a more tolerant SOH)
This is the unit normally found at Homely Depot:
This one looked fairly new so I took it home figuring to use it for cooling the garage during our hot summer months if it worked. I filled the 6 gallon reservoir, plugged it in and pushed the GO button. Sakes alive, the thing worked perfectly!
For the next few months I'd use it for personal comfort while running the still and running 40 or 50 gallons of water onto the ground from the condensers. After a particularly busy month, the wife commented on the jump in the water bill.
I knew I had to do something different so I grabbed an empty barrel, bought a fountain pump with a 7 foot head capability, some hose and fittings and made a barrel recirc system. That worked ok but the barrel got really hot after an extended run and I'd have to dump water on the ground to make room for fresh.
Standing in the shop doing some reloading and enjoying the blessed cool my find was putting out when I took a hard look at the still connections and inspiration hit. I dumped the recirc barrel and recovered the fountain pump, opened the swamp cooler and located all the water and electrical connections and went to work. This what resulted:
The next day was the acid test. I filled the boiler with a batch of feints, closed it up, fired up and started the cooler. Throttled the product condenser where I normally have it...a small stream and opened the reflux valve all the way. Once the column heated up I turned down the heat and the column temp dropped clean to 120f for equalization. I let it sit for a half an hour feeling the cooling lines. Plenty of heat coming from the reflux and into the cooler and ambient temps coming back into system. So far so good.
I turned down the reflux and began takeoff still feeling for heat in the product condenser. I set the temperature gradient and left it that way for the remainder of a four hour run checking the coolant level once an hour and the cooler worked perfectly throughout.
After shutting down I checked the reservoir one last time and found that I had only lost less than half of the capacity...less than three gallons for the entire run on a 70 degree day and at least 80 inside the garage. Not only did this work for cooling the still, it kept me cool in the garage while running.
I've got a winner!
tp (and a more tolerant SOH)
)