Y duct from tent exhaust to outside house and rest inside room with active intake at window?

waring192

Active Member
Hello,

I have a room around 3m x 2.5m and inside is a tent which is 2.4m x 1.2m so almost half the room is the tent and the tent goes from floor to roof.

The filter is a big 1.2m x 0.4m (200mm duct) and air is pulled through by the 200mm extractor. I was originally going to pump straight outside through a hole in the wall but was thinking could I have a Y junction and keep 50% inside the room and also run an active intake into the room? It will increase the humidity but I could always buy a dehumidifier. Just for these winter months when its cold outside.

Also, using an active intake which is also 200mm and similar CFM as the extraction into the room (not tent) so it heats up before entering the large passive vents, what 20% should I be running into the room to maintain negative pressure? I will also have a window open slightly.

Cheers people.
 

Hiphophippo

Well-Known Member
Do you not have bugs where you live I would be so worried about bugs with all that outside access through your intake and the open window. You should be good at the 20-30% I’d just adjust the loovers in the y to regulate air flow to get exactly what you want. are you going to continuously exhaust? Or are you going to do a scheduled air exchange?
 

waring192

Active Member
Do you not have bugs where you live I would be so worried about bugs with all that outside access through your intake and the open window. You should be good at the 20-30% I’d just adjust the loovers in the y to regulate air flow to get exactly what you want. are you going to continuously exhaust? Or are you going to do a scheduled air exchange?
Cheers for the reply. I have my AC Infinity S8 Fan hooked up to its 69 Pro Controller at the moment while im finishing my Home Assistant version which also does my nutrient dosing etc etc.

The extraction is based on a PID controller so like a thermostat but never goes below 20% so smell goes out through filter. PID controller also turns on my heater if needed when lights are off etc. I can just close the window I guess and just intake directly through the wall with a a 200mm intake which I will make it run % below the extraction at all time to maintain neg pressure. The intake will pass through an airbag with filters so all good.
 

Hiphophippo

Well-Known Member
Cheers for the reply. I have my AC Infinity S8 Fan hooked up to its 69 Pro Controller at the moment while im finishing my Home Assistant version which also does my nutrient dosing etc etc.

The extraction is based on a PID controller so like a thermostat but never goes below 20% so smell goes out through filter. PID controller also turns on my heater if needed when lights are off etc. I can just close the window I guess and just intake directly through the wall with a a 200mm intake which I will make it run % below the extraction at all time to maintain neg pressure. The intake will pass through an airbag with filters so all good.
Sounds like you got a good plan. I’d run like that and see how the air quality and stuff is and maintaining with temps and humidity. Happy growing.
 

024matters

Active Member
Im not HVAC expert but i guess you will have bigger pressure drop with this Y connection, especially if one side is longer than other. So ill suspect drop in airflow in regard how it works now (so a little less than half of your current airflow on one side of Y). With this room size and tent i think you will gain some temperature rise you desire but i would try to run room intake on lower setting to have it on ~equal airflow as the Y part exhausting into the room. Some experimenting needed, have fun
 

waring192

Active Member
Hmm, my other idea was as you know my room size I about 3.2m x 3m x 2.2 (about 60% bigger than the tent so not much room at all really). Just over 2 x (2.4m x 1.4m x 2.2m) so I could fit one next to each other with about a 30cm gap between and about 40cm x 240cm at the end where the door is.

I dont intend on putting in a second one the same size, maybe a small 1.2m x 1.2m x 1.m for seedling and veg. I run 6 plants in total in the 36lt RDWC pots in the main tent and the header etc. I would have to have a separate header tank a the nutes would be different but I can get 4 lid top for the 36lt pots so I bought them and two extra 36lt pots and a header. I just need the seed/veg tent, light and then onto my next question:

Anyone using a small air con with heat pump unit in a sealed room? I have a small window which is double glazed and I can seal it. For the door I could add one flaps or something to stop air getting in and close the window air vents. I know it's not cheap but at least when im out I dont have to keep any heating on in the house and would be perfect for summer.

Im running 2 x 600w Lumatek Zeus Pro 2.7 in the tent which will be lowered and dimmed instead of being kept at height. If I was to go for a decent air con with heat pump unit do you think thats the way to go then just vent out the tent into the room through the carbon filter to keep it smelling fresh. I can then explore adding Co2 etc maybe?
 
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