Need help choosing an air conditioning unit

[watsongreenthumb]

You could open the AC up and bypass some of the air so it does not go across the evaporator or block it off, effectively making it smaller.

ABSOLUTLEY don't do this. your just going to cause the evaporator coil to freeze over and eventually burn up the compressor. it will also pull tons of amperage as the evap coil starts to freeze, at best that pops your breaker at worst it starts a fire. just put the ac in the window, set it to the temp you want, and you will be fine.

 

[Three Berries]

ABSOLUTLEY don't do this. your just going to cause the evaporator coil to freeze over and eventually burn up the compressor. it will also pull tons of amperage as the evap coil starts to freeze, at best that pops your breaker at worst it starts a fire. just put the ac in the window, set it to the temp you want, and you will be fine.

My dehumidifier does this regularly. Once the evaporator freezes it shuts the compressor off. There is a temp sensor on the evaporator. Once it is above the point they have set above freezing then it comes back on again.

 

[watsongreenthumb]

If it freezes it should shut off the compressor until it thaws. My dehumidifier does but keeps blowing air. When it's thawed the compressor comes back on.

dehumidifiers have auto defrost cycles because they are designed to be able to remove moisture down to lower temperatures near 40f ambient. air conditioners DO NOT have this feature and are not meant to freeze over. restricting the airflow out of the ac is absolutley not something you want to do ever, it will be hugely inefficient as well as eventually destroying the compressor.

 

[Three Berries]

dehumidifiers have auto defrost cycles because they are designed to be able to remove moisture down to lower temperatures near 40f ambient. air conditioners DO NOT have this feature and are not meant to freeze over. restricting the airflow out of the ac is absolutley not something you want to do ever, it will be hugely inefficient as well as eventually destroying the compressor.

More than likely my dehumidifier needs a charge or is over charge. It's a POS used Sandy Storm ebay special. I would really be surprised if there isn't some sort of protection on a window AC unit. We uses to use thin sheets of fiberglass matting over the front as filters at work..

 

[watsongreenthumb]

My dehumidifier does this regularly. Once the evaporator freezes it shuts the compressor off. There is a temp sensor on the evaporator. Once it is above the point they have set above freezing then it comes back on again.

like I said dehumidifiers have auto defrost so that they can still dehumidify down to roughly 40f ambient, at that temperature the evaporator temperature could be 20f and so moisture will freeze as it goes across the coil, therefore the dehumidifier has to be able to auto defrost the coil. like you said some models do this by shutting off the compressor and continuing to run the fan. A window air conditioner does not have this feature and will continue to run until either the breaker pops, the thermal overheat switch on the compressor trips(if it has one), or the compressor its self or some of the wiring burns up. hopefully the breaker will pop before the last one happens, but its not a given because window air conditioners are not usually run on their own circuit so the amperage of the breaker is usually much higher than the amperage the aircon will pull during normal operation, especially if its a smaller 5k or 7k btu model.

 

[watsongreenthumb]

yeah if your dehu is low on refrigerant is will freeze over the evap coil at a much higher temperature, like room temperature. theres nothing wrong with using a better filter with a window ac, I do so myself because the screen filters they come with are garbage and will allow all sorts of crap to pass through and dirty up the evap coil. fiberglass mat probably isnt the best choice though, I like to use quilt batting from walmart, its basically the same stuff carbon prefilters are made of but I just use a thin layer, to improve filtration without killing the airflow.

 

[Three Berries]

like I said dehumidifiers have auto defrost so that they can still dehumidify down to roughly 40f ambient, at that temperature the evaporator temperature could be 20f and so moisture will freeze as it goes across the coil, therefore the dehumidifier has to be able to auto defrost the coil. like you said some models do this by shutting off the compressor and continuing to run the fan. A window air conditioner does not have this feature and will continue to run until either the breaker pops, the thermal overheat switch on the compressor trips(if it has one), or the compressor its self or some of the wiring burns up. hopefully the breaker will pop before the last one happens, but its not a given because window air conditioners are not usually run on their own circuit so the amperage of the breaker is usually much higher than the amperage the aircon will pull during normal operation, especially if its a smaller 5k or 7k btu model.

Like I said my POS dehumidifier does not and it is worthless below 70F. And like I said I would be surprised to see any AC unit without a temp sensor on the evap coil. How many are running right now with clogged up coils?

 

[watsongreenthumb]

ok, got a 10.000 btu ac to cool the entire room, thanks everyone for the reply
now i'm making myself a carbon filter, store brought ones are expensive where i live, for what i looked already i cold make one for less than 1/5 the price, not sure if i should use pellets or grain activate coal, i could get access to grain that 1mm to 4mm mixed or 5mm pellets(for what i gatter most comercial filters use a 2" layer of charcoal so that's what i am going with), what would do better?
if the grain restrict the airflow too much but filter better i could add another 100cfm fan and would still be way cheaper, any ideas?

as far as carbon your lucky to live in Australia where all the good carbon come from so I bet its pretty cheap. I would go with a thick 2.5 inch layer of the pelletized carbon, CAN filters use a carbon called ckv-4, i think its a 4mm pellet and they use a 2.56 inch layer. the pelletized carbon allows more airflow so the depth can and should be thicker. 2" would work okay too though. I recommend the pelletized because it seems like the companies who use it basically just dump it in there and maybe shake it or something to get it settled, where as the companies that use 2" granular carbon seem to use some sort of machine to really pack it in there tightly and uniformly and I think that would be harder to do properly on a diy project. just my 2 cents, I am not in the carbon filter manufacturing biz but I have taken apart and repacked several filters of both kinds with fresh carbon and like I said, the ckv-4 is just settled in there nicely whereas the granular stuff is really jammed in there tightly and uniformly. I have also found the pelletized ckv-4 to last much longer, but seems to need a thicker bed depth to really work well. I have also noticed that the high end filters using pelletized carbon always have a thicker bed depth (like 2.5 -2.7 inches) whereas the granular stuff is usually thinner, like 2 inches maybe 1.8.

 

[watsongreenthumb]

Like I said my POS dehumidifier does not and it is worthless below 70F. And like I said I would be surprised to see any AC unit without a temp sensor on the evap coil. How many are running right now with clogged up coils?
[/QUOTE


window ac's have whats called a thermistor, its a temp sensor of sorts, really a mechanical device that senses the incoming air temp and adjusts the refrigerant flow to suit it. it only works within a set range though and doesn't have any ability to adjust the compressor speed. (except on the newest inverter compressor models) Its also just measuring the incoming air temp, not the evap coil temp. yes lots of window a/c's have dirty coils and that can cause all the problems I have mentioned in the last few posts. most newer window units will have a thermal overload switch that will shut the unit down after the compressor overheats due to the coil being frozen over, but its something you want to avoid happening not something you want to do on purpose...

 

[watsongreenthumb]

I dont know why my above post is stuck as a quote but

 

[POTNU]

as far as carbon your lucky to live in Australia where all the good carbon come from so I bet its pretty cheap. I would go with a thick 2.5 inch layer of the pelletized carbon, CAN filters use a carbon called ckv-4, i think its a 4mm pellet and they use a 2.56 inch layer. the pelletized carbon allows more airflow so the depth can and should be thicker. 2" would work okay too though. I recommend the pelletized because it seems like the companies who use it basically just dump it in there and maybe shake it or something to get it settled, where as the companies that use 2" granular carbon seem to use some sort of machine to really pack it in there tightly and uniformly and I think that would be harder to do properly on a diy project. just my 2 cents, I am not in the carbon filter manufacturing biz but I have taken apart and repacked several filters of both kinds with fresh carbon and like I said, the ckv-4 is just settled in there nicely whereas the granular stuff is really jammed in there tightly and uniformly. I have also found the pelletized ckv-4 to last much longer, but seems to need a thicker bed depth to really work well. I have also noticed that the high end filters using pelletized carbon always have a thicker bed depth (like 2.5 -2.7 inches) whereas the granular stuff is usually thinner, like 2 inches maybe 1.8.

i already went with the non pelleted carbon lol, did not have the patience to wait for a answer, all the diy models i looked at online uses this type, going make the filter extra long for the needs of my flower room to be safe so i don't need so much static pressure from the exhaust to pull air from it, i think 50cm or 20in should be enough, going to do a test run and if needed be i will think about swapping for the pellets or using another equal exhaust inline to increase pressure, since they are not expensive, looks like a bathroom exhaust.
thanks for the reply anyway

 

[watsongreenthumb]

i already went with the non pelleted carbon lol, did not have the patience to wait for a answer, all the diy models i looked at online uses this type, going make the filter extra long for the needs of my flower room to be safe so i don't need so much static pressure from the exhaust to pull air from it, i think 50cm or 20in should be enough, going to do a test run and if needed be i will think about swapping for the pellets or using another equal exhaust inline to increase pressure, since they are not expensive, looks like a bathroom exhaust.
thanks for the reply anyway

no worries man, granular should be fine. out of curiosity how expensive is carbon in aus? its pretty pricey here since it all gets imported from austraulia

 

[postmanwatching]

i would stay away from window units... the old ones were bad but the new ones are even worse...
there is no drain for the water...it take the water from tray and throws it up for cooling...mold city...

 

[POTNU]

no worries man, granular should be fine. out of curiosity how expensive is carbon in aus? its pretty pricey here since it all gets imported from austraulia

I don't live in aus lol, i'm from Brazil
got 5kgs of coal for what would be around 18 usd, enough to fill the filter 2 to 3 times think, going to finish assembly tomorrow, and good carbon filter here go from round 75usd up, the coal with the pvc tubing is going to amount to around 20-30usd, pain in the ass to drill all the holes lol, but worth it.

i would stay away from window units... the old ones were bad but the new ones are even worse...
there is no drain for the water...it take the water from tray and throws it up for cooling...mold city...

thanks for the tip, my unit has the option to drain the water or do what your have said, but for easy of mind going to sprays some air disinfectant now and them inside of it to kill any trace of mold.

 

[Astral22]

Hey, i'm a new grower and i'll be exhausting in the same room also, with an AC unit and a dehumidifier. One thing i would suggest, be careful of carbon dust particles, it's not healthy to breathe it in. I read somewhere that you should use a vacuum cleaner to pull off the carbon dust from the filter.
First connect your fan to the filter the opposite way, so the fan blows INSIDE the filter to push all the dust to the edges. (do this through a window) Then simply vacuum the filter from outside, pulling from every little hole. And try not to shake the filter too much. I think carbon pellets emit lest carbon dust than granules. Personally i will also use a layer or 2 of pantyhose at the end of the ducting, attached with a rubber band. Hopefully it catches the carbon dust and doesn't restrict the airflow too much.

 

[POTNU]

Hey, i'm a new grower and i'll be exhausting in the same room also, with an AC unit and a dehumidifier. One thing i would suggest, be careful of carbon dust particles, it's not healthy to breathe it in. I read somewhere that you should use a vacuum cleaner to pull off the carbon dust from the filter.
First connect your fan to the filter the opposite way, so the fan blows INSIDE the filter to push all the dust to the edges. (do this through a window) Then simply vacuum the filter from outside, pulling from every little hole. And try not to shake the filter too much. I think carbon pellets emit lest carbon dust than granules. Personally i will also use a layer or 2 of pantyhose at the end of the ducting, attached with a rubber band. Hopefully it catches the carbon dust and doesn't restrict the airflow too much.

i'm sure its not healthy, there's even a lung disease associated with miners that work on coal mines
i did ran the coal i got trough a 4mm strainer to take the excess of dust off and the smallest pieces that could restrain the airflow too much
going to put a piece of air conditioner on the fan intake and let it run fome some times to see if it would still pull particles from the filter even when the coal is not grinding up against itself

 

[Inner.peace]

i'm sure its not healthy, there's even a lung disease associated with miners that work on coal mines
i did ran the coal i got trough a 4mm strainer to take the excess of dust off and the smallest pieces that could restrain the airflow too much
going to put a piece of air conditioner on the fan intake and let it run fome some times to see if it would still pull particles from the filter even when the coal is not grinding up against itself

C

Carbon is not so bad as silica and even azbest for lungs (silicosis azbestosis). But not in coal miner but miners in mines where silica stones are mined. Or worse - workers who worked in azbest factories in past. Nowadays these factories do not exist anewhere in world i hope.

A chronic lung disease caused by inhaling asbestos fibers-Asbestosis - Symptoms & causes - Mayo Clinic

Exposure to asbestos fibers causes this chronic lung disease. It may be decades before signs and symptoms such as shortness of breath and coughing appear.

www.mayoclinic.org