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Condensation on exhaust duct from winter

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Condensation on exhaust duct from winter

Fabio456 29 Replies 3,002 Views
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Fabio456

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Long time grower. Gaining popularity among my family and friends as the freebie pot man. I love growing. So easy and fun. So i did a major upgrade to my indoor because of it, this last summer.
5x10x8, 8 inch exhaust. Acrylic glass housing for window. 4x4 bed, with a mix on the other side. A/C infinity
I gotten everything setup and running. First harvest comes in, and im stoked. Called my friends to help trim. Reamend phase, fall time. Everything is working out JUST as planed.

Winter hits. Im still growing. I find it so much easier to control environment when its cold outside.
Half way through a veg grow, late November, We get some crazy cold snaps(upper central). All of a sudden there is pools of water below my exhaust tubing, and tons of standing water on it. the condensation from hot and cold was intense.
I ended up shutting down my grow, until i figure this problem out. Dont want to ruin my house

Has anyone else experienced this? and if so, how did you fix it?
Some things i think i could change. Insulated duct work, and backdraft dampener. But i fear with such a large exhaust, that wont be sufficient. ie. molding the insulation
 
Has anyone else experienced this? and if so, how did you fix it?
Nope, but the weather certainly can affect our growing environment.

Some things i think i could change.
Knowing more about your setup would help.

What are the temperature ranges, lights on/lights off? Do you have a dehumidifier, humidifier or a heater?

The plants themselves increase the humidity, especially when they're large.
 
Nope, but the weather certainly can affect our growing environment.


Knowing more about your setup would help.

What are the temperature ranges, lights on/lights off? Do you have a dehumidifier, humidifier or a heater?

The plants themselves increase the humidity, especially when they're large.
im sorry, but this in unimportant to the problem im facing. as the condensation forming is on the outside of the tent, on the exterior of the duct. the exchange of hot and cold air. but i will answer
large in home dehumidfier. 3500 square foot area
temp and humidity are VPD based .9-1.2
it is indoors. heater is not required
one 4x4 bed averages 2 plants
2 1x4 beds with strawbs
1 30 gallon for autos
1 15 gallons for mother plant
1 15gallon salad garden
 
the condensation forming is on the outside of the tent, on the exterior of the duct. the exchange of hot and cold air.
So, you must be exchanging inside and outside air. Is that right?
 
What’s the temperature difference between the outside and inside of your tent? The only way to reduce condensation is to remove humidity and increase airflow. If you have a 70 degree grow room in a 45 degree basement when your RH is high, the cooler air hits the outside surface of the grow tent and warms up leaving all of the moisture content of the air to pool on the warmer surface. I’d work on dehumidifying the outside air around your tent and that should fix the problem.
 
I actually just ran into this very issue over the past couple of weeks, and I will share what I did to fix my particular situation.

I have my tents set up with the exhaust venting up through an attic access panel and I previously hat it running strait up (vertical) and tied into an existing roof vent. This was working great, until the cold snap hit.

The problem is that when warm humid air hits cold try air......viola! Condensation!

I decided to replace my duct hosing with flexible insulated ducting. (It's basically just regular old flexible ducting that is wrapped in insulation). I also figured that the straight run was just going to allow any condensation to run straight down and pool up inside of the ducting or pooling on top of the attic access panel. My solution was to make a short vertical run and then slope it slightly downward to a dryer vent hood that I installed through the wall and stucco, completely venting all of the air, smell and water vapor completely out of the house.

We had some below zero temperatures this past week and no more condensation problems!!!

So my solution was #1. insulated ducting and #2. letting gravity assist in letting any condensation drain out through the exterior dryer vent hood.

I will add that during the below zero snap we had, I had some sweet ice sickles formed on the outside vent hood!

Good luck with resolving your issue and getting the grow fired back up!

Smoke
 
The solution is simple. Don't vent outside and waste your lungroom. Your pumping all your needed humidity, hot or cold air outside and throwing it away. I just vent in my office lungroom and let the HVAC system deal with it. In the winter the added humidity is wonderful and in the summer the extra humidity helps drop the wet bulb temp across the evaporator for a 22 degree deferental from return air and discharge air temp and adding a bit more efficiency to the AC.
 
The solution is simple. Don't vent outside and waste your lungroom. Your pumping all your needed humidity, hot or cold air outside and throwing it away. I just vent in my office lungroom and let the HVAC system deal with it. In the winter the added humidity is wonderful and in the summer the extra humidity helps drop the wet bulb temp across the evaporator for a 22 degree deferental from return air and discharge air temp and adding a bit more efficiency to the AC.
this is asking for mold, mildew, and warping of any wood in the house. NEVER SUGGEST EXHUASTING INTO YOUR LUNGROOM. defeats the purpose of a lungroom, sorry not sorry for caps

What’s the temperature difference between the outside and inside of your tent? The only way to reduce condensation is to remove humidity and increase airflow. If you have a 70 degree grow room in a 45 degree basement when your RH is high, the cooler air hits the outside surface of the grow tent and warms up leaving all of the moisture content of the air to pool on the warmer surface. I’d work on dehumidifying the outside air around your tent and that should fix the problem.
78 in tent, 73 outside. 35% outsiode varies inside
this is an issue of condensation from hot air being exhausted, and cold air entering the tub from outside. causeing condensation to form on the exhaust ducting
Like a soda can sweating in the summer
Good luck with resolving your issue and getting the grow fired back up!

Smoke
i assumed this was the correct course of action. I might add a P-trap to the bottom of the duct J.I.C. (like the bathroom facet)
thank you!



I will post pics, when i get my tent up n running again. Make y'all jelly
 
I've got this right, your getting condensation on/at the exhaust side?

That's normal ime the moisture is condensing with cold turning it back to water.

I had to remove about 1 litre from a short length of ducting 😲
So I poked a hole in the ducting (after taping it for strength) and put a strip of capillary in the hole to allow it to drain into a tub.
You need some loose form of a V shape so it drains where you want it to or maybe elevate the ducting so it can run outside/water trap?
Acoustic ducting helps insulate short runs but over distances it's always going cool sufficiently to condense.

Good luck 🤞
 
Okay, but I've been doing it for years without any problems. 🤣
enjoy the health problems and destroyed framework 😂

but seriously. You really need to stop. I am legit worried about your home, and your health. You are asking for issues
and if your renting, you would be on the hook for damages
 
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enjoy the health problems and destroyed framework 😂

but seriously. You really need to stop. I am legit worried about your home, and your health. You are asking for issues
and if your renting, you would be on the hook for damages.
LMFAO!!!!
 
enjoy the health problems and destroyed framework 😂

but seriously. You really need to stop. I am legit worried about your home, and your health. You are asking for issues
and if your renting, you would be on the hook for damages
I assure you, we're fine. The house is fine. I can't imagine why you're so worried because there certainly are solutions. We have air conditioning for the house and a dehumidifier in the lung room. Each tent has an environment controller. The exhaust fans have charcoal filters. We monitor the CO2 level. We have excellent air quality in our home and in our lung room.
 
I assure you, we're fine. The house is fine. I can't imagine why you're so worried because there certainly are solutions. We have air conditioning for the house and a dehumidifier in the lung room. Each tent has an environment controller. The exhaust fans have charcoal filters. We monitor the CO2 level. We have excellent air quality in our home and in our lung room.

good luck
 
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It would only be condensation if the air inside was gettting below dew point. With it being a 8” exhaust I would try using a piece of insulated duct. You can get it at Home Depot. Would be worth a shot.
 

good luck
Better to be a ass hole than a useless lying POS. Lets look at your POS links simpleton drama queen,,,, shall we. Your first one is about a so called commercial grow in a residential setting and appears to be fiction and the hyperlink to study results are marketing adds. No study results anywhere. Dr. Christian Thurstone is a marketing specialist. A PHD in funny papers. Next you post a write up about combustion in the living space focusing on wood burning in the living space. How does that apply to anything in this thread drama queen? And then a 3rd grade level write up about the health benefits to plants in the living space. That you want to exhaust out of the house and get no benefit from. I don't think you are smart enough to grow weed and at best are a troll.
 
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