40+ lbs with 12 Plants in 2 Rooms on a Flip

TBH I was able to get away with an 80 pint kenmore in Missouri where we had more humidity, that was in a 12kW room. Here I have two 10 kW rooms and an 80 pint won't touch it now with the coco in play. When I was running soil I had low humidity and had to run a swamp cooler. So changing to coco really blew up the transpiration rates.

So I am more confused than ever when it comes to dehu sizing. One thing I do know, a good dehu is way better than a shitty one. The Quest pulls more water in 5 minutes than 3 of my other dehus do in a couple hours.

So I really love the quest dehumidifier. I have some plans for it's big ass after this harvest.

• Put 3 inch heavy duty casters on it so I can roll it easy. (Ordered)
• Move it to the space under my stairs that is currently only used as storage, then using the ducting kit plumb it through the wall into room B.
• Build a device with a contactor and delay on break timer so I can plug that into my autopilot environmental controller and have it control the dehumidifier through it's 24v control circuit. I find the internal humidistat setting needs to be changed often to keep the humidity correct, this will fix that by letting the autopilot decide whats up. This will avoid having the dehumidifier run during a vent cycle as well. The adjustable delay on break timer will keep the dehumidifier from being short cycled and encountering rotor lock from vapor pressure on the high side of the refrigerant circuit. I have found it needs about 5 minutes to safely restart without popping it's breaker so I will set the delay to 7 minutes. This delay happens from the time the dehumidifier is turned off so if 6 minutes has passed when it's turned back on it will wait 1 minute. If it's >=7 minutes after then it won't wait. This is handy for HID lighting controllers as well, if the power flickers it waits for the lamps to cool before trying to restart them although some new digital ballasts have their own internal delay.

I am babbling... lol

Babble on. No worries

Does it produce a lot of heat while dehumidifying?

Keesje said:

Babble on. No worries

Does it produce a lot of heat while dehumidifying?

Click to expand...

Ya know it's not as bad as I would expect for such a large unit. When my lights are off my autopilot takes over to handle heat by venting, this gives me a room exchange at lights out. When lights are off it pushes it down to 75F and lets it rise to 80F. Its taking about an hour and 20 minutes to kick on a vent cycle. Here in Colorado, most all of the time that actually drops the humidity since it usually so low outside. It doesn't seem to strain the AC.

I changed out the RO filter cartridges today. I decided to order a flow rate meter. It will let me know when output is slowing down so I know it's time to change the membrane. It will also total the gallons output. I have another meter that tallys the gallons input.

I have been following your grow journal here. How is it going?

Meter testing and calibration party. lol

So I picked up one of those 3 channel networkable temp / humidity dealios. Pretty cool. I mainly got it so I could get alerts sent to my phone when temp or humidity is out of spec. Works great. No I am not concerned about it being secure as my grow is legal.

Some data collected from room a.

what dehumidifier would you recommend for a smaller 2kw room renfro?

sandman83 said:

what dehumidifier would you recommend for a smaller 2kw room renfro?

Click to expand...

Depends a lot on your climate. Maybe an 80 pint?

Renfro said:

Depends a lot on your climate. Maybe an 80 pint?

Click to expand...

My 60 pint works great in my 7x14 room.

I'm sure an 80 would be even better.

Besides the climate where you live, it will also depend on how many plants you have and what kind.
Some 'drink' 8 liter per square meter per day, others 12 liter per square meter.

Keesje said:

Besides the climate where you live, it will also depend on how many plants you have and what kind.
Some 'drink' 8 liter per square meter per day, others 12 liter per square meter.

Click to expand...

This is very true. When I just changed from soil to coco with the same number of plants and pot size, I went from not even needing dehumidification to needing a LOT during peak drink. Blew me away.

Renfro said:

Depends a lot on your climate. Maybe an 80 pint?

Click to expand...

sorry I had more meant, is there a good brand or model you recommend? I figured sizing would be plant mass dependant as you indicated.

So I got a new networked temperature / humidity dealio. A sensor for each room. I got it because I wanted to get text message notifications if the temp / humidity gets out of range.

Here is a chart for room A. Seeing the temp and humidity graphs really shows the temp drop / RH% rise happen at lights out (3:45 AM in this case).



In my rooms the dehumidification creates heat and when the room hits 80 my intake (cold dry air) runs it down to 75F to push some humidity out but not get it so cool that the dehumidifiers don't work. As you can see it's a balancing act. When my plants are at peak drink the dehumidifiers require some help from my ventilation, good thing I live in a fucking desert with low RH% lol.

sandman83 said:

sorry I had more meant, is there a good brand or model you recommend? I figured sizing would be plant mass dependant as you indicated.

Click to expand...

Quest, Phoenix, Fantech, Drizair, Ideal Air and EBAC are all really good ones that I have used. As to more consumer grade units the only experience I have is pretty dated. I have an old Kenmore 80 pint that still works like a champ but a lot can change in 20 years. Make sure the one you get will "auto restart after power outage". This is critical for 2 reasons. The obvious one of course but also if you intend to plug it into an environmental controller it needs to fire up when power is turned on and off at the receptacle. Most dehumidifiers have inaccurate hygrometers and thus you either have to figure out where it needs to be set to achieve your set point or use an external controller and set the dehumidifier to "always on". Another issue with old school analog "knob" style hygrometers is they need a different setting for different temperatures. My Quest has one internally, I have to adjust it for day / night as it needs a harder working (lower) RH% setting when the lights are off or it will shut off too soon. It seems to be about a 8 - 9% difference in my case. Simply bypassing the internal controller (an option) lets me use my Autopilot to turn it on and off, eliminating the issue.

Renfro said:

My Quest has one internally, I have to adjust it for day / night as it needs a harder working (lower) RH% setting when the lights are off or it will shut off too soon. It seems to be about a 8 - 9% difference in my case. Simply bypassing the internal controller (an option) lets me use my Autopilot to turn it on and off, eliminating the issue.

Click to expand...

Does your dehumidifier have a day and night mode?
How does the device know it is night? Is it with a clockwork or with a light sensor?

megrowweed said:

Hey, sorry if i post this here but i need some help quick. My plant is in week 4 of flower and has gone really bushy inspite of me defoliating it in week 2. What should i do defoliate again? Or do i just leave it here are some pictures for reference.

Click to expand...

Dont defoliate, pull the branches down and expose more branches...thats all I do, I barely defoliate during flowering until the last two weeks to expose buds and harden them up

Keesje said:

Does your dehumidifier have a day and night mode?
How does the device know it is night? Is it with a clockwork or with a light sensor?

Click to expand...

Re read my post. It's not right, needs adjusted twice a day. lights on and lights off.

Renfro said:

So I got a new networked temperature / humidity dealio. A sensor for each room. I got it because I wanted to get text message notifications if the temp / humidity gets out of range.

Here is a chart for room A. Seeing the temp and humidity graphs really shows the temp drop / RH% rise happen at lights out (3:45 AM in this case).

View attachment 4431171

In my rooms the dehumidification creates heat and when the room hits 80 my intake (cold dry air) runs it down to 75F to push some humidity out but not get it so cool that the dehumidifiers don't work. As you can see it's a balancing act. When my plants are at peak drink the dehumidifiers require some help from my ventilation, good thing I live in a fucking desert with low RH% lol.

Click to expand...

What size intake are you running?
Do you have separate intakes for each room or a single intake that mixes between rooms?
Are you recirculating the air between all rooms or do you have dedicated cooling / dehumidifying?

Also when do you cut back on your co2?

I love those sensors you got to monitor temp and RH. Whats the highest temp you’ve ran your rooms before seeing negative impacts? For some reason I though you were running hotter.