I smell antifreeze

[MAK1]

I have a 3X4 tent with 4 medium sized plants well into flowering.
I have the tent in my garage in a very cold environment outside. Heating the space while exhausting all the humidity out the roof got to be way to expensive to keep warm. I decided to vent back into the garage so I need a dehumidifier to keep from ruining my house with all the water vapor. Those giant carbon filters we use help remove the pot smell.
This single filter setup left a strong antifreeze smell in my garage. I put another filter on the other end of the tube. (2) 6x18 carbon filters have nearly removed that antifreeze smell.
What is that smell? What is the chemistry behind that sickly sweet smell like ethylene glycol. It is from the tent not anything other than that. I am putting down more molasses than called for but that doesn't account for this strong lingering smell.

 

[PlanetJ]

I vent tents directly back into the room they stand in, and regulate rh with a window .. I have never smelled anything like this. I would assume my filter is full and letting stuff through, and replace it.

I dont have a (de-) humidifier, maybe that has a leak in your setup, no clue how they work and what gasses are involved.

 

[MAK1]

I vent tents directly back into the room they stand in, and regulate rh with a window .. I have never smelled anything like this. I would assume my filter is full and letting stuff through, and replace it.

I dont have a (de-) humidifier, maybe that has a leak in your setup, no clue how they work and what gasses are involved.

The smell came first. That is why I say it is from the tent. The filter is from one previous grow with only 3 plants. I thought these filters would last longer. I had a replacement but that's what I put on the other end.
post; I forgot that I had a bunch of plants ending with 3 survivors, 2 of which were useful. Anyhow, the filter my have excessive moisture issues.
The weather has recently has been cold but, prior the daily humidity spikes to 95+ and drops to 35-40 RH. The daily temperature usually has a 35-40 degree swing that makes venting outside problematic as well. All that vented air needs to be replaced and heated.
Growing this late in the year was never part of my plan. Due to starting a week late then, messing with my plants too often that slowed growth in veg. Eight weeks in veg for plants that didn't get all that big. The list of learning events is long. Adding to my late season troubles is choosing to grow a plant with a longer flowering time.
I said earlier I had been venting through the roof. This worked great in the summer, as expected. The power-head (the fan) was rather loud so, I decided to put it in my unheated attic I WILL NEVER DO THIS AGAIN. I worked great until the weather turned cold. All that hot humid air hits the cold metal hose in the attic and now there is condensation running down the tube into the fan housing and blade. Because of heating expenses I was shutting off the extraction air at night trying to save money. All the cold air came down into the tent through the filter causing the tent temp to drop to 60-65. Now I know why. I just happened to stay out in the garage the morning it froze up. Normally I would just turn on the fan and go back for more coffee. I heard a strange sound and there was no air moving. Water was dripping from a wet filter inside the tent (OMG, I think I just answered my problems) This could have caused an electrical short. I will never do this again. The noisy fan is in the garage. All of this adds to why I am venting back into my garage.
I suppose a new filter inside the tent is in order. If the smell is from the wet filter then forget the question. I think the smell is from the grow and will be removed by a new dry filter. What is that smell?

 

[PlanetJ]

The filter is from one previous grow with only 3 plants. I thought these filters would last longer.

they should, I have them last a grow or 6 at least.

Its not just the ladies or whatever is in their medium that you are smelling? Is the same smell present in the tent?

 

[Auggie]

I dont have a (de-) humidifier, maybe that has a leak in your setup, no clue how they work and what gasses are involved.

A dehumidifier is just an air conditioner. Shouldn't smell.

What is the chemistry behind that sickly sweet smell like ethylene glycol.

This is a reach, and I'm almost ready to call BS on ME.
But, did you know that aphids secrete a sweet sticky honey like substance? Yea, and ants farm them for it.

I smelled something like that in an indoor that had a raging aphid infection. Look for shiney leaves, turn a few over and look for bugs.

Prolly not that ... but, check everything.

 

[MAK1]

they should, I have them last a grow or 6 at least.

Its not just the ladies or whatever is in their medium that you are smelling? Is the same smell present in the tent?

No, the tent smells as expected.

 

[MAK1]

A dehumidifier is just an air conditioner. Shouldn't smell.


This is a reach, and I'm almost ready to call BS on ME.
But, did you know that aphids secrete a sweet sticky honey like substance? Yea, and ants farm them for it.

I smelled something like that in an indoor that had a raging aphid infection. Look for shiney leaves, turn a few over and look for bugs.

Prolly not that ... but, check everything.

There is no obvious answer here for me. I am suspicious of a few things. 1. The possibly wet filter. 2. A 5 gallon pot that has recently been flushed with 6 gallons of water (this may have washed away my smell, time will tell). 3. I have been adding too much molasses and it has fed something unwanted, the soil smells normal. The effluent smells ok. 4. Just getting more fresh air.
I think solving the problem will be easier and faster than figuring out what I am smelling.

 

[013]

I’ve never had anti-freeze scent in my garden or produce, any chance charcoal filter absorbed the scent from garage? An old growers trick was to hang bananas above flowering plants, the ripening fruit gives off ethylene gas, maybe your nose is finely tuned for that

 

[Auggie]

I think solving the problem will be easier and faster than figuring out what I am smelling.

AND you may solve it without even knowing how ...



.

 

[MAK1]

I’ve never had anti-freeze scent in my garden or produce, any chance charcoal filter absorbed the scent from garage? An old growers trick was to hang bananas above flowering plants, the ripening fruit gives off ethylene gas, maybe your nose is finely tuned for that

The garage is new with a polished concrete floor. All my machines are in my shed with gasoline. The smell is strongest if I shut off the exhaust fan. Come back after an hour and the humidity is up with the smell. Perhaps some sort of aseptic vampire protozoa blew up the bacterial microbial balance? I added some leftover feed water once that I should have dumped. The food didn't smell bad though it didn't smell as nice as it did when I mixed it together 2 days earlier. Live and learn. Living large over here, LOL

 

[MAK1]

I’ve never had anti-freeze scent in my garden or produce, any chance charcoal filter absorbed the scent from garage? An old growers trick was to hang bananas above flowering plants, the ripening fruit gives off ethylene gas, maybe your nose is finely tuned for that

I am such a space case. I need to look back at my notes to see when I added chopped up banana peels. Seriously, I just can't stop adding stuff from my kitchen. Sort of a precomposed addition of nutes. One more reason to compost first? Like Dirty Harry, I just gotta know my limitations.
Bananas really? I have a stupid looking grin on my face right now. This may be my eureka moment. I will seriously think about bananas.
Thanks

 

[Phytoplankton]

Maybe you’re smelling ozone from the electrical equipment, particularly, if as you say, it got wet.

 

[013]

Yup I know - right?

ripening bananas are said to excite flowering cannabis plants….

 

[bluter]

venting indoor is a problem. if you are moving that much rh it needs some place to go. the air will bottle up and cause odour and other issues. a dehum can help but that sounds like a lot of water, it may have issues keeping up.

never vent directly up. even furnaces will have a sideways bend that connects to a vertical chimney pipe. the pipe extends below the connection for a ways and is capped to collect condensation. otherwise they are vented sideways direct to outside so condensation is not an issue. grow spaces need to be vented similar.

you may be moving a bit too much air for the environment. you can get a fan with control that will work on temp, rh or both, depending how you want it set.


considering the minimal number of plants you shouldn't have to move that much air. especially in veg, your requirements will increase in flower though.


if you are running hid / hps the smell is likely ozone. if you are running led it could be condensation burning off the chips. i would check on the lighting. if condensation is forming on the tent walls it will need to be solved for quickly.

 

[MAK1]

Yup I know - right?

ripening bananas are said to excite flowering cannabis plants….

Yes indeed. Ethylene does many things at different stages of a plants life cycle. Even after the harvest ethylene will speed the ripening process.
FYI, bananas emit ethylene from the stem. Bananas ripen slower if the stems are covered with wax or plastic just like the organic bananas we buy. Of course it works for other bananas as well.

 

[MAK1]

venting indoor is a problem. if you are moving that much rh it needs some place to go. the air will bottle up and cause odour and other issues. a dehum can help but that sounds like a lot of water, it may have issues keeping up.

never vent directly up. even furnaces will have a sideways bend that connects to a vertical chimney pipe. the pipe extends below the connection for a ways and is capped to collect condensation. otherwise they are vented sideways direct to outside so condensation is not an issue. grow spaces need to be vented similar.

you may be moving a bit too much air for the environment. you can get a fan with control that will work on temp, rh or both, depending how you want it set.


considering the minimal number of plants you shouldn't have to move that much air. especially in veg, your requirements will increase in flower though.


if you are running hid / hps the smell is likely ozone. if you are running led it could be condensation burning off the chips. i would check on the lighting. if condensation is forming on the tent walls it will need to be solved for quickly.

Thank you for you thoughts on this. Things like this generally don't happen because of a problem but, they happen due to one thing after another, after another. This is how disasters happen.
To begin I did not want to put a hole in the side of my new home. I vented into the garage until the humidity began to change the color of the concrete. It was still warm outside. An effective quick fix was to make a hole in the sheetrock and run the 6" tube up to the ridge vent. As long as I was up there I decided to add the fan expecting it would all be done by the end of October at the latest.
A series of events added to gardening issues and seed choice have pushed this way past the calendar deadline. My issues mount. I never would have needed all this environmental controls for an earlier season grow. The exhaust tube is getting a lot of condensate. From the moment it leaves the tent (12") it hits a cold environment so condensation was actually coming into the tent when I turned off the fan. Also cold air was coming into the tube so my night temps were dropping to 60-65 degrees. I think this added to slow growth/development.
I got a Vivosun speed controller to match the Vivosun fan. Save your money. Could you be so kind as to offer a suggestion on that RH/temp exhaust fan setup? I looked at the lumber yard but no find. I got a large dehumidifier that can handle 50 pints daily. Nice controls that work to whatever RH it is set to. I now need to keep the garage RH low to limit condensation on the overhead insulated door, it still has metal edges.
Now I am venting into my garage. Added a second filter. Added a dehumidifier. Closed the hole in the attic so no more ice cold air needs to steel my propane. Heating the area in November cost me about an extra 90 gallons of propane compared to Decembers estimate and November barely ever got below zero. A proper side vent would have not let this happen. Condensate on an exhaust vent might garner unwanted attention.
How much air to exhaust? When I bought all this stuff what I read was that I needed to move a ridiculous volume of air and the one I have has no effective way to slow the 3 speed fan. The additional speed is nearly worthless. The fan needs so much energy just to start spinning that any reduction in electrical input and the motor stops spinning.
The humidity inside the tent is never high enough. The interior of the tent is not wet except for the once wet filter. I need a humidifier inside the tent to keep it higher. Only after a heavy watering does the RH come up above 50%. Another week or 4 and I can harvest.
The flowers are growing again either because of improvements in soil makeup, nutes, moisture etc. OR is this the bud swell I am waiting to see.

 

[Phytoplankton]

There's nothing wrong with RH in the 50's during flower (or even veg), mine averages 40-50% in flower, slightly higher in veg (60%). Higher RH can make a breeding ground for bud rot. All parts of the plant transpire water, on leaves it evaporates quickly into the environment, but buds are tight and the transpired water doesn't evaporate and sits inside the buds, hence bud rot. Good air circulation can really help keep the buds dry and rot free.

 

[Diatomacious]

The exhaust tube is getting a lot of condensate.

You need insulated vent duct... this is even a problem in home AC systems and why your house duct work is always insulated (not so much for heat loss as for condensation). Any time you have a surface with hot on one side and cold on the other you will get condensation. Just don't let it build up humidity in your new home or you will have mold growing on everything in the house.

 

[MAK1]

You need insulated vent duct... this is even a problem in home AC systems and why your house duct work is always insulated (not so much for heat loss as for condensation). Any time you have a surface with hot on one side and cold on the other you will get condensation. Just don't let it build up humidity in your new home or you will have mold growing on everything in the house.

Thank you.
I closed the hole in the ceiling and am using a dehumidifier. IF I put a hole it needs to be on the sidewall. There is no good way to stop the cold. Venting directly back inside and the drying the air is the cheapest way for me. Anyhow, the plants are all just about ready to pull. Done just in time as winters subzero temperatures are only a week away. No way to avoid it, winter is here.

 

[013]

I dont run extraction since I live in the sticks with no close neighbors but I’ve heard a lot of good stuff about AC Infinity fans with their built in controller for setting thresholds.

yep the cold is here too MAK1. Hope you had a Merry Christmas