An interesting spin on this would be to collect condensate water from your air conditioner which you can then use to fill evaporative cooler. Of course, there’s a humidity level sweet spot since if the air humidity is too low you won’t collect enough condensate water from the airco to be useful. But if the humidity is too high the evaporative cooler won’t cool you.
Mike, I represented, two Evaporative Cooling (swamp cooler) manufacturers for several years. Sizes ranged from small, 18" to 48" 220v 10,000 cfm units. Great for outdoor environments, but not for enclosed spaces. Could be used in an RV with windows open, could lower temp by >35 degrees with low humidity but, in my opinion, not practical for a closed environment in conjunction with AC. Great outdoors though!
I have used permanently mounted (wall and rooftop) swamp coolers very successfully in the Sierra Nevada foothills where the humidity is very low. As stated by others, these coolers draw in outside air and pressurize the inside space. One selectively opens windows to direct the flow of cool high humidity air as desired. When it is cooler outside than inside, the water supply and internal pump can be turned off making the unit into a sort of whole house fan. I see no reason that a permanently mounted swamp cooler could not be installed as a supplemental cooling system in an RV. It would be most useful in boondocking situations since the energy requirements are low. The problem is that swamp coolers use a great deal of water which is usually in short supply when boondocking. It is also important to clean a swamp cooler regularly to avoid growing mold in the fiberous element that is saturated with water and in the water reservoir and pumping system. Unfortunately, humidity and mold are really bad things for RVs. Clearly, alternative creative designs could minimize these problems. Winterization would also be required.
I have also used a Honeywell portable swamp cooler with sone success. We used one to cool my wife’s medium RV sized art studio before we installed a mini split. The unit has a reservoir that holds about a 1/2 - 1 gallon of water which keeps it going for a few hours. As noted by others, a door or window must be kept open. That said, the unit does a pretty good job of blowing a stream of cool air in the direction set by a set of louvers on the top front of the unit which can be set in a fixed direction or in oscillating mode to spread the cool air around. It works pretty well all things considered but I’d prefer a mini split any day. All that said, I see an opportunity for a portable RV swamp cooler that chat could work in some RV / camping situations. As Mike suggested, using ice packs to minimize water consumption might help assuming the use of solar panels to cool the ice. I do think someone should run the numbers and do confirming experiments comparing the energy use of an optimized swamp cooler to a mini split which can clearly be operated with solar panels and batteries. I’d love to see more mini split’s designed for use in RVs. And, you get heating and cooling with a properly designed heat pump.
As you said, they use a lots of water, so you have to have a convenient way to keep water level up so the pumps can pull water over the filters. Used one in my house for years in Albuquerque. But when monsoon season come (July/August) and the humidity goes up, then they do not work so well.
The first time I saw mini splits we’re in the islands south of Florida. They were so efficient and I was questioning why the USA did not encourage this type of cooling system. They are quiet and very efficient.
Here's a comment on how to make an inexpensive swamp cooler for a small RV that runs on 12V. Not my design; that belongs to FIGJAM from the Burning Man eplaya forum. I made one and used it to cool my 13 foot camper. If you Google "FIGJAM swamp cooler" you will get tons of hits from folks who built off of FIGJAM's original design, but the original is here: https://eplaya.burningman.org/viewtopic.php?f=280&t=33842
That post has 146 pages!!! of comments from folks who have tested and modified and tweaked the design. So don't go with his first design in the thread. Instead, a good tutorial on building it is at this site:
This is a fantastic design that works amazingly well and is easily run on solar power alone. By the way, FIGJAM is an acronym for F#@& I'm Good, Just Ask Me, and I have to say, yes, he is brilliant.
The campground where I am located in Southern AZ has a gigantic swamp cooler in the huge clubhouse. Since Arizona is dry it works well but the management keeps the windows open while using the swamp cooler as the humidity will feel like a swamp. For me who lived in Florida over 55 years I’d like a bit of a swamp. So to resolve the high humidity produced by the swamp cooler by keeping the windows open it resolves the issue. The room does cool down even with the windows are open. This might be affective for Arizona due to its low humidity, but may not work for other states.
system works on air flow. So windows have to be open for the air to flow. Air flow is selected by which windows and how much they are open. Not much humidity is added since the air is too dry on the outside. But wait for monsoon season (July/August) when the humidity goes up, then swamp coolers do not work to well.
The campground where I’m located in dry Arizona has a huge clubhouse. When the swamp cooler is on it is connected to the water hose and all the windows are open. The manager explained that the open windows are necessary to keep the humidity down or everything would be damp and. wet
I have had a swamp cooler on my house for years. When the humidity outside is usually around 10 %, yet my swamp cooler has never raised my humidity above 25%. (except when monsoon season hits, then humidity goes up and the swamp cooler does not work very well
That’s how my folks used to cool the car driving down the highways in the late 40s-early 50s. That said, I’ve used a small swamp cooler made from a 5-gallon bucket, a computer fan and a very small water pump in a desert environment. It sits outside and blows the conditioned air into our trailer and exits out the vent. Humidity MUST be below 20%! On a 105° day it’s a relief to step inside, especially with a small fan pushing the air around. Powered by a separate 12-volt battery. We run it maybe 8 hours a day and the battery lasts about 6-7 days.
I see a lot of people use ice in their coolers. Actually, I guess there are two different types of cooling you can achieve. First is true "evaporative" cooling whereas the moisture, picked-up from the fan, via the pads, evaporates and cools the air, just like perspiration works on our bodies. This method requires a source of outside air exchange (ventilation), to avoid over-humidification. The second method, using ice, somewhat negates the evaporation and cools by adding air cooled by the cold water. I had major sports teams use this method in order to get cooling on the sidelines even on hot, humid nights. Probably not cost effective, but better than being hot!
I've had many swamp coolers over the years including two rooftop RV units that worked great. Like Roy stated though, you cannot use a portable inside a space that draws it's air from that space. In order for a swamp cooler to work as designed it has to use outside air, so you draw outside air thru the cooler and into the space where you keep the windows open so the air can be constantly changed. If you put the unit inside the space the humidity will build quickly to greenhouse levels.
I should add that the coolers I had on RVs had a cfm of 750 on high and were reversible so even in humid areas they made great ventilation fans, just run the unit dry which won't hurt it at all.
Used them back in the day when AC was too expensive for working class folks. In a dry climate they work. Not as cooling as AC but way better than nothing. Advantage is low cost, low power requirements, low tech. Disadvantage is they need a water supply. Either regularly hand fill or a float valve arrangement.
I got a small one that uses ice cubes(we used in our house when AC went out last yr). I was surprised how well it worked, granted it was still humid but the air blowing across the cubes help cool off the bedroom.
An interesting spin on this would be to collect condensate water from your air conditioner which you can then use to fill evaporative cooler. Of course, there’s a humidity level sweet spot since if the air humidity is too low you won’t collect enough condensate water from the airco to be useful. But if the humidity is too high the evaporative cooler won’t cool you.
Mike, I represented, two Evaporative Cooling (swamp cooler) manufacturers for several years. Sizes ranged from small, 18" to 48" 220v 10,000 cfm units. Great for outdoor environments, but not for enclosed spaces. Could be used in an RV with windows open, could lower temp by >35 degrees with low humidity but, in my opinion, not practical for a closed environment in conjunction with AC. Great outdoors though!
I have used permanently mounted (wall and rooftop) swamp coolers very successfully in the Sierra Nevada foothills where the humidity is very low. As stated by others, these coolers draw in outside air and pressurize the inside space. One selectively opens windows to direct the flow of cool high humidity air as desired. When it is cooler outside than inside, the water supply and internal pump can be turned off making the unit into a sort of whole house fan. I see no reason that a permanently mounted swamp cooler could not be installed as a supplemental cooling system in an RV. It would be most useful in boondocking situations since the energy requirements are low. The problem is that swamp coolers use a great deal of water which is usually in short supply when boondocking. It is also important to clean a swamp cooler regularly to avoid growing mold in the fiberous element that is saturated with water and in the water reservoir and pumping system. Unfortunately, humidity and mold are really bad things for RVs. Clearly, alternative creative designs could minimize these problems. Winterization would also be required.
I have also used a Honeywell portable swamp cooler with sone success. We used one to cool my wife’s medium RV sized art studio before we installed a mini split. The unit has a reservoir that holds about a 1/2 - 1 gallon of water which keeps it going for a few hours. As noted by others, a door or window must be kept open. That said, the unit does a pretty good job of blowing a stream of cool air in the direction set by a set of louvers on the top front of the unit which can be set in a fixed direction or in oscillating mode to spread the cool air around. It works pretty well all things considered but I’d prefer a mini split any day. All that said, I see an opportunity for a portable RV swamp cooler that chat could work in some RV / camping situations. As Mike suggested, using ice packs to minimize water consumption might help assuming the use of solar panels to cool the ice. I do think someone should run the numbers and do confirming experiments comparing the energy use of an optimized swamp cooler to a mini split which can clearly be operated with solar panels and batteries. I’d love to see more mini split’s designed for use in RVs. And, you get heating and cooling with a properly designed heat pump.
As you said, they use a lots of water, so you have to have a convenient way to keep water level up so the pumps can pull water over the filters. Used one in my house for years in Albuquerque. But when monsoon season come (July/August) and the humidity goes up, then they do not work so well.
The first time I saw mini splits we’re in the islands south of Florida. They were so efficient and I was questioning why the USA did not encourage this type of cooling system. They are quiet and very efficient.
I’m not sure if it’s a valid concern, would it be possible for mold building up if the cooler is not regularly cleaned?
Yes, that’s certainly a concern.
Here's a comment on how to make an inexpensive swamp cooler for a small RV that runs on 12V. Not my design; that belongs to FIGJAM from the Burning Man eplaya forum. I made one and used it to cool my 13 foot camper. If you Google "FIGJAM swamp cooler" you will get tons of hits from folks who built off of FIGJAM's original design, but the original is here: https://eplaya.burningman.org/viewtopic.php?f=280&t=33842
That post has 146 pages!!! of comments from folks who have tested and modified and tweaked the design. So don't go with his first design in the thread. Instead, a good tutorial on building it is at this site:
https://www.theplayalabs.com/swamp-cooler
This is a fantastic design that works amazingly well and is easily run on solar power alone. By the way, FIGJAM is an acronym for F#@& I'm Good, Just Ask Me, and I have to say, yes, he is brilliant.
The campground where I am located in Southern AZ has a gigantic swamp cooler in the huge clubhouse. Since Arizona is dry it works well but the management keeps the windows open while using the swamp cooler as the humidity will feel like a swamp. For me who lived in Florida over 55 years I’d like a bit of a swamp. So to resolve the high humidity produced by the swamp cooler by keeping the windows open it resolves the issue. The room does cool down even with the windows are open. This might be affective for Arizona due to its low humidity, but may not work for other states.
system works on air flow. So windows have to be open for the air to flow. Air flow is selected by which windows and how much they are open. Not much humidity is added since the air is too dry on the outside. But wait for monsoon season (July/August) when the humidity goes up, then swamp coolers do not work to well.
The campground where I’m located in dry Arizona has a huge clubhouse. When the swamp cooler is on it is connected to the water hose and all the windows are open. The manager explained that the open windows are necessary to keep the humidity down or everything would be damp and. wet
I have had a swamp cooler on my house for years. When the humidity outside is usually around 10 %, yet my swamp cooler has never raised my humidity above 25%. (except when monsoon season hits, then humidity goes up and the swamp cooler does not work very well
That’s how my folks used to cool the car driving down the highways in the late 40s-early 50s. That said, I’ve used a small swamp cooler made from a 5-gallon bucket, a computer fan and a very small water pump in a desert environment. It sits outside and blows the conditioned air into our trailer and exits out the vent. Humidity MUST be below 20%! On a 105° day it’s a relief to step inside, especially with a small fan pushing the air around. Powered by a separate 12-volt battery. We run it maybe 8 hours a day and the battery lasts about 6-7 days.
I see a lot of people use ice in their coolers. Actually, I guess there are two different types of cooling you can achieve. First is true "evaporative" cooling whereas the moisture, picked-up from the fan, via the pads, evaporates and cools the air, just like perspiration works on our bodies. This method requires a source of outside air exchange (ventilation), to avoid over-humidification. The second method, using ice, somewhat negates the evaporation and cools by adding air cooled by the cold water. I had major sports teams use this method in order to get cooling on the sidelines even on hot, humid nights. Probably not cost effective, but better than being hot!
I've had many swamp coolers over the years including two rooftop RV units that worked great. Like Roy stated though, you cannot use a portable inside a space that draws it's air from that space. In order for a swamp cooler to work as designed it has to use outside air, so you draw outside air thru the cooler and into the space where you keep the windows open so the air can be constantly changed. If you put the unit inside the space the humidity will build quickly to greenhouse levels.
I should add that the coolers I had on RVs had a cfm of 750 on high and were reversible so even in humid areas they made great ventilation fans, just run the unit dry which won't hurt it at all.
Used them back in the day when AC was too expensive for working class folks. In a dry climate they work. Not as cooling as AC but way better than nothing. Advantage is low cost, low power requirements, low tech. Disadvantage is they need a water supply. Either regularly hand fill or a float valve arrangement.
I got a small one that uses ice cubes(we used in our house when AC went out last yr). I was surprised how well it worked, granted it was still humid but the air blowing across the cubes help cool off the bedroom.