Indoor AC/Heat unit with no external vent?
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I used to rent an apartment that had a rectangular AC/Heat unit on the wall, and it did not seem to have any connection to the outside air. It just had an electrical plug that was plugged into the wall.
I now live in another apartment, and would like to buy one of those. But, I can't seem to find it. I've been looking for "Heat Pump" units, and they all seem to involve an external fan that is placed outside.
Where I currently live, I would not be permitted to have any external units (extensions, fans, etc). Also, I would not be permitted to have a window AC unit, and not even an exhaust hose at the window. This is why I would like the unit to be 100% indoor.
Could you provide me with some recommendations? Thanks very much.
By the way, I don't really need the unit to heat. I only need an AC unit. I have a studio of about 350sq' in the city, and without any AC unit it gets 85-90 degrees inside in the summer, and extremely humid. Anything that could get it down to even 75 degrees and reduce the humidity in 1/2 would be helpful.
I now live in another apartment, and would like to buy one of those. But, I can't seem to find it. I've been looking for "Heat Pump" units, and they all seem to involve an external fan that is placed outside.
Where I currently live, I would not be permitted to have any external units (extensions, fans, etc). Also, I would not be permitted to have a window AC unit, and not even an exhaust hose at the window. This is why I would like the unit to be 100% indoor.
Could you provide me with some recommendations? Thanks very much.
By the way, I don't really need the unit to heat. I only need an AC unit. I have a studio of about 350sq' in the city, and without any AC unit it gets 85-90 degrees inside in the summer, and extremely humid. Anything that could get it down to even 75 degrees and reduce the humidity in 1/2 would be helpful.
#2
Welcome to the forums.
There's a good chance that if it was on the wall it had some type of outside access.
You can produce heat with electric and not needing outside access but with A/C it will only cool the room if it can discharge the hot air outside.
Even those free standing A/C units need to get rid of the heat with a small discharge hose thru the window. Without outside access it will create more heat than it can produce cold causing the room to get hotter.
There's a good chance that if it was on the wall it had some type of outside access.
You can produce heat with electric and not needing outside access but with A/C it will only cool the room if it can discharge the hot air outside.
Even those free standing A/C units need to get rid of the heat with a small discharge hose thru the window. Without outside access it will create more heat than it can produce cold causing the room to get hotter.
#3
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The basic operation of air conditioning involves transferring heat from one place to another. So the heat that's absorbed on the inside of the apartment needs to be rejected somewhere. Hence the outdoor section of units.
I'm afraid nothing exists to meet what you described, beyond units that use chilled water from a chiller.
I'm afraid nothing exists to meet what you described, beyond units that use chilled water from a chiller.
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Thank you for your time with this.
Is there anything that I could use that doesn't have any vent to the outside. Roughneck77 is what you were describing an Evaporator? I remember reading about what you describe but can't recall the name. Would this be helpful for a hot/humid 3 month summer (hot/humid all day and night)...Boston though, so not as intense as farther south.
I have a very good de-humidifier, but it just makes it hotter in temperature. It can reduce the humidity by 1/2 about, but doesn't help the temperature itself, due to not emitting the hot air outside.
I now found this list of Evaporators
http://www.homedepot.com/b/Heating-V...Z2bcubz?NCNI-5
For say a 400sq' place, could you recommend one or two?
Lastly, I noticed that they are best in dry climates...I wonder if using my de-humidifier with it would be useful?
Thanks again.
Is there anything that I could use that doesn't have any vent to the outside. Roughneck77 is what you were describing an Evaporator? I remember reading about what you describe but can't recall the name. Would this be helpful for a hot/humid 3 month summer (hot/humid all day and night)...Boston though, so not as intense as farther south.
I have a very good de-humidifier, but it just makes it hotter in temperature. It can reduce the humidity by 1/2 about, but doesn't help the temperature itself, due to not emitting the hot air outside.
I now found this list of Evaporators
http://www.homedepot.com/b/Heating-V...Z2bcubz?NCNI-5
For say a 400sq' place, could you recommend one or two?
Lastly, I noticed that they are best in dry climates...I wonder if using my de-humidifier with it would be useful?
Thanks again.
Last edited by 2784a; 04-23-17 at 03:19 AM.
#5
Evaporative coolers (also known as "swamp coolers") work reasonably well in very dry climates such as Arizona by adding moisture to the air. However, in your location in Massachusetts, I suspect that you are dealing with moderate to high humidity in the summer months. The last thing you want is to add more humidity to the air.
What Roughneck was referring to (chilled water) is what many industrial and large apartment buildings use. They have "radiators" in each room and in the winter months, they circulate hot water for heat. In the summer, they circulate cold (chilled) water through them. They may also use a fan to disperse the cold air. A chilled water system has to be designed/built into the building. It's not something you can add yourself later.
What Roughneck was referring to (chilled water) is what many industrial and large apartment buildings use. They have "radiators" in each room and in the winter months, they circulate hot water for heat. In the summer, they circulate cold (chilled) water through them. They may also use a fan to disperse the cold air. A chilled water system has to be designed/built into the building. It's not something you can add yourself later.
#6
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Any of those units in the link will increase your humidity even more.
Any sort of cooling utilizing refrigerant will need a vent in and out for heat rejection. As I meantioned before the whole refrigeration process is about "moving" heat. Running air conditioning means the indoor coil is absorbing heat and the outdoor coil then rejects it.
The previous unit you meantioned may have actually had a vent to outdoors, or was a chilled water unit connected into a chilled water plant within the building.
What do other tenants in this building do for cooling?
Any sort of cooling utilizing refrigerant will need a vent in and out for heat rejection. As I meantioned before the whole refrigeration process is about "moving" heat. Running air conditioning means the indoor coil is absorbing heat and the outdoor coil then rejects it.
The previous unit you meantioned may have actually had a vent to outdoors, or was a chilled water unit connected into a chilled water plant within the building.
What do other tenants in this building do for cooling?
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Interesting.
If I use an Evaporative Cooler with a de-humidifier, would this be a good option? I can adjust my de-humidifier to any setting from 80% humidity to 35%, so maybe I could find a setting for it that would work well with the Evaporative Cooler? Or am I failing to understand how these work?
(The building is a 3 story large house that I used to live in. Each floor is 1 rental unit. Those rectangular, wall units are on each floor, in random areas. I think they are LG brand. About 3 feet across, and 1.5 feet tall. Each floor uses these for AC in particular rooms. I no longer live there though.
If I use an Evaporative Cooler with a de-humidifier, would this be a good option? I can adjust my de-humidifier to any setting from 80% humidity to 35%, so maybe I could find a setting for it that would work well with the Evaporative Cooler? Or am I failing to understand how these work?
(The building is a 3 story large house that I used to live in. Each floor is 1 rental unit. Those rectangular, wall units are on each floor, in random areas. I think they are LG brand. About 3 feet across, and 1.5 feet tall. Each floor uses these for AC in particular rooms. I no longer live there though.
#8
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The LG brand box you described is a mini split. The indoor unit is piped into an outdoor unit somewhere on the building. Refrigerant flows through the pipes to achieve heating and cooling.
Using an evaporative cooler in a humid climate is not a wise choice. The cooler is adding moisture to the air that the dehumidifier is trying to remove.
Evaporative coolers are only suitable for hot, dry climates like the desert.
Using an evaporative cooler in a humid climate is not a wise choice. The cooler is adding moisture to the air that the dehumidifier is trying to remove.
Evaporative coolers are only suitable for hot, dry climates like the desert.
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I see.
The only option that I can think of is to obtain an in-apartment (non-window) unit that has a hose that is put in the bottom of a window. The problem is that all of my windows are not vertical window-panes that are risen and closed, but instead, one window pane that is rolled outward up to 90 degrees. I would have to create something myself to seal off the open area, like a plastic film, or tape a piece of plastic, which would be about 3 feet high.
My de-humidifier exhausts hot air out of the top. I wonder if I could obtain a vent hose that would catch it, and which I could put in the window.
Any recommendations would be helpful. Thanks.
The only option that I can think of is to obtain an in-apartment (non-window) unit that has a hose that is put in the bottom of a window. The problem is that all of my windows are not vertical window-panes that are risen and closed, but instead, one window pane that is rolled outward up to 90 degrees. I would have to create something myself to seal off the open area, like a plastic film, or tape a piece of plastic, which would be about 3 feet high.
My de-humidifier exhausts hot air out of the top. I wonder if I could obtain a vent hose that would catch it, and which I could put in the window.
Any recommendations would be helpful. Thanks.
#10
that has a hose that is put in the bottom of a window
Also, I would not be permitted to have a window AC unit, and not even an exhaust hose at the window. This is why I would like the unit to be 100% indoor. Could you provide me with some recommendations?

I would like the unit to be 100% indoor
Last edited by ray2047; 04-23-17 at 08:56 AM.
#11
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The discharge from the dehumidifier is the dehumidified air. Exhausting it outdoors wouldn't lower your humidity and would cause your apartment to go into a negative pressure, causing more hot air to be pulled in. Using a swamp cooler would increase humidity and could cause mold problems.
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Thanks for all of this and for educating me on these things.
There is an adequate electrical supply, it's just that the homeowner wouldn't want to pay the additional expense, as electricity is included in the rent. I'm renting a studio in a home
I have a back door that goes to the backyard...up 8 steps to the backyard. There is a main door, and a screen door. I might try to do a single-hose unit there, by having the door open 6" or so, threading the hose into the opening, and sealing off the rest with a saran-wrap type of weather proofing. I can't use my two front windows, because the homeowner can see those windows and walks around that area often. With the backdoor being down the steps, and with the screen door (the bottom 1/4 is wood, with the screen above), I might be able to get away with it. But I wouldn't be able to do the dual-hose option. For 2-3 months it is 80+ degrees and high humidity, and fans don't do that much. The de-humidifier, despite that it is quite nice, doesn't help much - if anything, it makes it hot and dry. It will extract about 2 gallons of water every few hours.
There is an adequate electrical supply, it's just that the homeowner wouldn't want to pay the additional expense, as electricity is included in the rent. I'm renting a studio in a home
I have a back door that goes to the backyard...up 8 steps to the backyard. There is a main door, and a screen door. I might try to do a single-hose unit there, by having the door open 6" or so, threading the hose into the opening, and sealing off the rest with a saran-wrap type of weather proofing. I can't use my two front windows, because the homeowner can see those windows and walks around that area often. With the backdoor being down the steps, and with the screen door (the bottom 1/4 is wood, with the screen above), I might be able to get away with it. But I wouldn't be able to do the dual-hose option. For 2-3 months it is 80+ degrees and high humidity, and fans don't do that much. The de-humidifier, despite that it is quite nice, doesn't help much - if anything, it makes it hot and dry. It will extract about 2 gallons of water every few hours.
#13
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What do other tenants in this building do?
Single hose units don't work well. They pull conditioned air out of the space which then causes outdoor air to be sucked in.
My wife's grandparents have a single hose unit in their back room. Running constantly it maintains around 84-86* when it's over 90 outside. Uses a load of electricity too, their bill is substantially more when it's used.
Single hose units don't work well. They pull conditioned air out of the space which then causes outdoor air to be sucked in.
My wife's grandparents have a single hose unit in their back room. Running constantly it maintains around 84-86* when it's over 90 outside. Uses a load of electricity too, their bill is substantially more when it's used.
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I'm the only tenant in the house. A small studio in the daylight-basement. The owner lives in the rest of the house.
I had a single-hose unit in the past, in a different apartment. It was in just my bedroom. It was about 2.5 feet high, and the hose pumped hot air outside. The end of the hose had a 5" panel, which fit into the window, after I opened the window by 5". The fit was good, because the panel would extend to the exact width of the window. The unit cooled the place fairly well - about 74-75 or so in even 95 degree temperature with sun-facing windows. But, maybe it raised the electrical bill a lot. The room was small though - about 1/3 the size of my current studio. I think that such a unit might do well in my studio. Also, I have very low ceilings (maybe 7' high, or even 6' 10"), which should allow such a unit to cool the space fairly well, I suppose.
The heat for my unit is from hot water that is piped under the floor (stone floors). As such, there are no vents. I keep a window cracked all winter for at least some fresh air.
I had a single-hose unit in the past, in a different apartment. It was in just my bedroom. It was about 2.5 feet high, and the hose pumped hot air outside. The end of the hose had a 5" panel, which fit into the window, after I opened the window by 5". The fit was good, because the panel would extend to the exact width of the window. The unit cooled the place fairly well - about 74-75 or so in even 95 degree temperature with sun-facing windows. But, maybe it raised the electrical bill a lot. The room was small though - about 1/3 the size of my current studio. I think that such a unit might do well in my studio. Also, I have very low ceilings (maybe 7' high, or even 6' 10"), which should allow such a unit to cool the space fairly well, I suppose.
The heat for my unit is from hot water that is piped under the floor (stone floors). As such, there are no vents. I keep a window cracked all winter for at least some fresh air.
Last edited by 2784a; 04-23-17 at 11:36 PM.
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Is it possible to use an in-apartment, portable, AC unit (single-hose) with an overhead stove vent-hood as the ventilation for the single-hose? My vent-hood is large (2 feet across) and has two vent openings. I can easily remove one of the screens for one side, and thread a single-hose in there. The fit will not be even close to perfect, though, because the opening is large, square in shape, etc. I would simply fit the hose ending in that region. I think that 90+% of the AC exhaust would go into the vent-hood. I would have the vent-hood turned on, so that it would be exhausting the AC exhaust air. I'm thinking of getting a very small AC unit - one for a 200sq' room. My ceilings are very low (6'10" or 7'), so I think it will cool my entire place adequately. My only two windows are roll-out, small windows of a daylight basement place, and with screens, so there is no place to put an exhaust hose, unless I cut a hole in the screen, which I am not permitted to do. Anyway, I'm just curious if the vent-hood option is feasible for a very small AC unit.
#16
No reason to write duplicate posts 2 hrs apart, give people a chance to reply. Site has had a few issues recently.
#17
But, maybe it raised the electrical bill a lot.
it's just that the homeowner wouldn't want to pay the additional expense, as electricity is included in the rent.
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Hello,
I have a different question/topic below. I copied it again and in blue print.
(Ray2047 about your question. Regarding my apartment and lease, I pay over $1500.00 a month, it is maybe 350sq', it gets stifling hot and humid in the summer for 2 months, the homeowner has central AC for her 2000sq' house above me, no AC for my unit, the homeowner is cheap, I would get the smallest AC unit possible and use it only when home. By the way, the rental agreement does not prohibit an AC unit, and electric is included in the rent. No AC units will fit in the roll-out windows, and I don't want to ask the homeowner about doing a hose through the screen (putting a hole in the screen), for fear the homeowner will object to everything. I think it's fair to have an AC unit for use when it is above 80 and humid, given how much rent I'm paying, etc).
A Different Question
Is it possible to use an in-apartment, portable, AC unit (single-hose) with an overhead stove vent-hood as the ventilation for the single-hose? My vent-hood is large (2 feet across) and has two vent openings. I can easily remove one of the screens for one side, and thread a single-hose in there. The fit will not be even close to perfect, though, because the opening is large, square in shape, etc. I would simply fit the hose ending in that region. I think that 90+% of the AC exhaust would go into the vent-hood. I would have the vent-hood turned on, so that it would be exhausting the AC exhaust air. I'm thinking of getting a very small AC unit - one for a 200sq' room. My ceilings are very low (6'10" or 7'), so I think it will cool my entire place adequately. My only two windows are roll-out, small windows of a daylight basement place, and with screens, so there is no place to put an exhaust hose, unless I cut a hole in the screen, which I am not permitted to do. Anyway, I'm just curious if the vent-hood option is feasible for a very small AC unit.
I have a different question/topic below. I copied it again and in blue print.
(Ray2047 about your question. Regarding my apartment and lease, I pay over $1500.00 a month, it is maybe 350sq', it gets stifling hot and humid in the summer for 2 months, the homeowner has central AC for her 2000sq' house above me, no AC for my unit, the homeowner is cheap, I would get the smallest AC unit possible and use it only when home. By the way, the rental agreement does not prohibit an AC unit, and electric is included in the rent. No AC units will fit in the roll-out windows, and I don't want to ask the homeowner about doing a hose through the screen (putting a hole in the screen), for fear the homeowner will object to everything. I think it's fair to have an AC unit for use when it is above 80 and humid, given how much rent I'm paying, etc).
A Different Question
Is it possible to use an in-apartment, portable, AC unit (single-hose) with an overhead stove vent-hood as the ventilation for the single-hose? My vent-hood is large (2 feet across) and has two vent openings. I can easily remove one of the screens for one side, and thread a single-hose in there. The fit will not be even close to perfect, though, because the opening is large, square in shape, etc. I would simply fit the hose ending in that region. I think that 90+% of the AC exhaust would go into the vent-hood. I would have the vent-hood turned on, so that it would be exhausting the AC exhaust air. I'm thinking of getting a very small AC unit - one for a 200sq' room. My ceilings are very low (6'10" or 7'), so I think it will cool my entire place adequately. My only two windows are roll-out, small windows of a daylight basement place, and with screens, so there is no place to put an exhaust hose, unless I cut a hole in the screen, which I am not permitted to do. Anyway, I'm just curious if the vent-hood option is feasible for a very small AC unit.
#19
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Many range hoods don't even vent outdoors, they just recirculate air. Does yours vent outside?
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It definitely vents outside - it has a Low and High setting, and both settings vigorously suck air in, and there are no areas in my studio that the air is exhausted to any extent. I think that the exhaust might extend to an exhaust-opening in the backyard somewhere.
#21
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I would verify that it does go outdoors.
You will not be able to cook or use the stove with the hose there.
You will not be able to cook or use the stove with the hose there.