Choosing a Dehumidifier is Hard

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tobh

tobh

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i run a vremi 50 pint with auto drain. it's great for in flower, look forward to running it every crop as it drops the humidity in my office/grow room to an amazingly comfortable level for me while making the environment in the tent ideal for the ladies. great quality unit. and no, i'm not endorsed by them, simply a fan of a brand that is producing better quality than the likes of GE and other big box brands.
 
BigBlonde

BigBlonde

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Thanks to everyone who commented! I really appreciate how helpful the folks are here.

The gift of an air conditioner will help me get through the hot days and has seriously reduced the immediate need to buy a dehumidifier. I ran it on its cooling mode yesterday and on its dry mode last night. The overnight temperature dropped to 64F and the RH stayed below 60%. That shows the problem I have with high and low temperatures in a 24-hour period. This air conditioner makes the room cooler when it is in dehumidify mode, lowering the overnight temperature even further. So I definitely still need a dehumidifier.
 
CactusJack1

CactusJack1

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Im growing in basement and running 2 dehumidifers a 50 pint and 35 pint dumping about twice a day about 15 gallons. In winter im lucky to keep humidity at 35 percent but the girls dont seem to mind.
 
BigBlonde

BigBlonde

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Im growing in basement and running 2 dehumidifers a 50 pint and 35 pint dumping about twice a day about 15 gallons. In winter im lucky to keep humidity at 35 percent but the girls dont seem to mind.
I've never used a dehumidifier before, so I don't know what to expect. Nevertheless, 15 gallons seems like a lot. I don't doubt you, though. I've been tweaking that old air conditioner we were lucky to find, and it sure is making a difference. Even the humans like it better. The temp & RH are both in range and it's the hottest part of the day.

We probably won't grow during the winter. Most likely, we'll do two crops a year. Our thinking is that spring and fall would be best. It's too cold & humid during the winter and too hot during the summer. We only grow for the two of us, so two crops should be plenty. I'm also thinking a smaller tent would have been better for us, but it's too late to fret about that now.
 
BigBlonde

BigBlonde

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just remember dehumidifiers work through heating the space, so you'll need to contend with the heat discharged somehow
Yep! Thanks!

I'm reading reviews of dehumidifiers and heat is a common complaint. Ya gotta love some of the reviewers. One of them complained about the heat from the dehumidifier so he's running his A/C. I guess he doesn't know that air conditioners also dehumidify.

This makes our gifted A/C perfect for summer. I have it set to 78*F and the temperature inside the tent is staying close to that. The RH is staying between 49% and 55%. I turned it off at lights-off last night and the tent RH stayed within range all night. During the colder months, however, we'll still want a dehumidifier, so I'm still reviewing brands and models. I'm looking at Midea models now. They're looking good. We'll want the heat then.

So, it looks like we'll have an A/C unit for the hot months and a dehumidifier for the cold months. That sounds good to me!
 
RootsRuler

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Yep! Thanks!

I'm reading reviews of dehumidifiers and heat is a common complaint. Ya gotta love some of the reviewers. One of them complained about the heat from the dehumidifier so he's running his A/C. I guess he doesn't know that air conditioners also dehumidify.

This makes our gifted A/C perfect for summer. I have it set to 78*F and the temperature inside the tent is staying close to that. The RH is staying between 49% and 55%. I turned it off at lights-off last night and the tent RH stayed within range all night. During the colder months, however, we'll still want a dehumidifier, so I'm still reviewing brands and models. I'm looking at Midea models now. They're looking good. We'll want the heat then.

So, it looks like we'll have an A/C unit for the hot months and a dehumidifier for the cold months. That sounds good to me!
Did you ever get your exhaust fan issue sorted out?
 
BigBlonde

BigBlonde

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Did you ever get your exhaust fan issue sorted out?
Yes. I ordered an S6 this morning. I also ordered 8 feet of flexible ducting. They'll be here later in the week. I ordered the S6 because I'm waiting for their new WiFi controller.

The two 120mm fans actually work well, but they're noisy as heck. I could add a speed controller, but it's just better to get the right hardware and not have to worry about it. It became clear that peace at home was worth the money spent for a quiet fan. I may keep the smaller fans as a backup.
 
RootsRuler

RootsRuler

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S6 is the rotary style fan speed controller. You want the T6 with the controller 69 or is this a special order?
 
BigBlonde

BigBlonde

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S6 is the rotary style fan speed controller. You want the T6 with the controller 69 or is this a special order?
The plan is to replace the controller that comes with it when the new controller is available. I checked with a representative who said that's the best way to do it. I'll just have to live with the basic controller for a while.

Yesterday, the company's web site said the new controller would be available today. Today, it's saying there's no ETA available. I want the WiFi controller because Bluetooth doesn't work well here. I just about have to be standing next to the tent to get a signal. It must have something to do with the way this place was built.
 
Slickrick82

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I have a sensor in the tent and it has been very useful, but it only provides information. It doesn't control anything. Something I'm considering is that the Inkbird costs at least $40 and that money could be applied to buying a dehumidifier with more features.


I have wondered about where the best location for a sensor would be. I put mine at canopy level. It's nice to get lucky once in a while. 🙂


Good idea! I had been thinking about running my heater on a timer so it would run when the lights are off. Heat certainly makes a difference. I run a heater most nights, depending on the weather. It hasn't been enough to control the RH, however. This morning I turned it off after the lights had been on for almost two hours and the RH started to increase.


There certainly are a lot of dehumidifiers with lots of features. It's hard to know which to choose. I'm a techie at heart, so I am drawn to high-tech toys.



I'll probably get the dehumidifier with WiFi and remote monitoring and control. Knowing myself, I know I'll be wondering about what I didn't do if I don't do it.

I keep thinking that a temp & RH sensor in the room would be helpful. (We might put one outside, too.) So, by watching the two, the best setting for the dehumidifier could be determined. I keep wondering about how the air in the tent is continuously exchanged with the room air. The exhaust fans have combined (rated) CFM of four times the volume of the tent. Thus, theoretically, the air is being exchanged every 15 seconds. At that rate, the air can't be much different between the inside and the outside of the tent.

Here's a screen capture of the report from the sensor in the tent. It clearly shows the relationship between temperature and humidity. I turned off the heater in the room just after 6:45 AM and it's easy to see the effect. The outside temperature was in the 50s last night and we're supposed to have a hot day today. There's no A/C for the lung room, so I'll be fighting excessive heat most of the day.

View attachment 1266398

The RH has been worse lately even though the weather is hot now. I think it may be because the plants are large and transpiring more. I have two plants in a 4x4 tent. For the next grow, I plan to have four plants, so the transpiration is likely to be worse and dehumidifying will be even more important.

The good news for my next grow is that I will have learned so much doing this first grow and will be much better prepared. I have been taking "lesson-learned" notes and I'll have most of the equipment in place.
Yes everything on timers makes life easier
 
freezeland2

freezeland2

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The plan is to replace the controller that comes with it when the new controller is available. I checked with a representative who said that's the best way to do it. I'll just have to live with the basic controller for a while.

Yesterday, the company's web site said the new controller would be available today. Today, it's saying there's no ETA available. I want the WiFi controller because Bluetooth doesn't work well here. I just about have to be standing next to the tent to get a signal. It must have something to do with the way this place was built.
I have had my 69 wifi on order since June 16th. I was included in the back order purchase they allowed that was supposed to ship by July 15th. Even have that in writing on my invoice. Still no shipping…..
 
weed420420420420420

weed420420420420420

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Somebody should make an all in one dehumidifier and a/c that just sits in the room and does it's job without a window port.
 
BigBlonde

BigBlonde

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I finally made a decision about which dehumidifier to buy: A Midea. It's still in the box. I don't need it yet because the air conditioner is working well. We'll definitely need it when the rains begin. It has a lot of nice features, including settable humidity levels, a pump, WiFi and a large capacity.

Midea Dehumidifier   In the box
 
BigBlonde

BigBlonde

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I unboxed the new dehumidifier today. It seems to be good hardware. It works fine. Setup was easy. It's too warm to use it during the day, so I'll try running it tonight. The WiFi was easy to setup, too. I like that I can turn it on and off from the phone app. I can also set the target humidity from the app. I decided not to use the pump at first.

The initial experience wasn't without frustration, however. The phone app showed the wrong location for the ambient weather conditions. That's a small detail, but I decided to contact support anyway. After at least a half hour in a chat session, the issue remains unresolved. I knew I was in trouble when after asking for the model number, the representative had to ask what type of unit it was. It's hard to believe that information wasn't attainable from the model number. After we cleared that up, she asked which app I was using. I had to ask how many apps they have. I mean, the app I installed was the one from the QR code. So then I learned they have two apps. The one in the manual, evidently, is being deprecated. There's another on their web page. Unfortunately, the web page only would install the iPhone app and I have an Android phone. So, ultimately, what many reviewers said is true. The dehumidifier is very good, but the app is not. It does work for the essential functions, though. I just can't help but wonder why their programmers didn't think to add a setting for location. That seems pretty basic, to me, and will cost them at least one star on the review.
 
BigBlonde

BigBlonde

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I'm testing the new dehumidifier this morning. The picture is a report from the sensor inside the tent and shows the RH fluctuation during one hour of operation. The temperature in the tent was stable at 78F during the the hour. I have the target humidity set to 50%. Apparently, it has a plus or minus one percent range. I don't know if the two percent variation matters. The plants seem okay.

I also resolved the problem with the phone app. I finally was able to install the app from their web page. It turns out they're no longer using the one with the QR code in the documentation. Instead of fixing the location problem, they dropped location from the app. It was nice to see the weather condition in the app, but I can get that anywhere. Our plan is to add more sensors so we can see the conditions both in the lung room and outside the house.

Humidity Example   Screenshot 20220807 084732 SensorPush
 
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BigBlonde

BigBlonde

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I installed the new S6 this morning. I have it set to half speed. I don't have a smart controller because I'm waiting for the 69 WiFi controller. I have it pulling from the top back corner of the tent. The tent intake is at the bottom opposite corner. This fan is much quieter than the 120 mm fans I was using. The duct from ACI seems to be very good quality. This one is eight feet long, but collapses down to about six inches.

Hopefully this arrangement will help avoid light leakage during flowering. I'm going to flip soon, so I'm putting all the openings at the far side of the room from where we might have to enter when the lights are out.

My plan is to put the dehumidifier on the same side of the tent as the exhaust and intake.

S6 Installed   20220810 120554



This Intro to Growing Hemp that was in the box is cool, too. It's about 1/2 guide and 1/2 product catalog.

Intro to Growing Hemp cover   Scan 20220810
 
weed420420420420420

weed420420420420420

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well the room always still has warmer air doesn't it?
 
Moe.Red

Moe.Red

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well the room always still has warmer air doesn't it?
Hmmm, not sure what you mean.

Let's use the example of a refrigerator. Let's say your kitchen is hot, and you decide to open the freezer door to cool things off. Does it work?

About as much as putting a block of ice in the room. Then it melts.

If you try to cool your kitchen permanently by opening the freezer, you will actually succeed in heating it up. All of these types of products work by being a heat pump. They take heat and move it to a different place. A freezer moves that heat into the room it is in. Such a small space to worry about, not a big deal. But if you leave the freezer open, you will kick on the compressor and other electrical things that will actually get hot, the heat of which also goes into the room. You accomplish nothing except using electricity.

You have to have a heat sink for them to work. For an AC - that's the outdoors. That heat you are removing has to go somewhere.
 
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