I want to be able to grow year round and need some help on HVAC for the warm and cold seasons. My plan is to do a tent setup in my shed with a 400W MH/HPS main light and fluorescent or LED lights to supplement. I would do a max of 6-8 plants. How much is it going to cost for a decent HVAC setup that will allow me to do this year round, and does anyone have any experience with this kind of climate and setup? Thanks for the help!
I think an 8k btu portable a/c can handle a 400w in a NE summer. Get an air cooled hood that has removable glass (some of them have hinges and rivets) so you can add it in summer for cooler temps, and remove it in winter for the heat, to increase your efficiency. In cold temps you might want to consider growing autoflowers, as you can run a 20/4 light cycle thus heating most of your grow with your lights, instead of running a 1500w heater that doesn't grow shit for 12 hours a day. Run the 4hr dark cycle during the day when temps are highest, with the sun warming up your shed during the day you might even be able to get away without using a heater at all. If 400w doesn't adequately heat your grow then get an extra light (or a bigger one), or use foam insulation board around your tent, which would be a good idea anyway. No sense whatsoever running watts through a heater when you can use the watts off your lighting instead, and get more bud out of it in the process. Finally, I'd use this little gadget to control my exhaust fan: It can be set to turn your vent fan on and off for heating or cooling purposes, allowing precise control over your temps. The reason you put this on your vent fan instead of your a/c or heater is because you want temps to go a bit too high or a bit too low so your vent fan kicks on and refreshes the co2 in your grow. If you were planning on spending a grand or two on full environmental controls then you can bump up your lighting to 2kw or more, fill out your whole shed, but I don't think it would be cost effective on a 400w grow. After growing in an unconditioned basement for 6 years I've found this to be the most efficient way to deal with changing temps without spending a fortune on equipment that sucks a ton of energy and doesn't actually grow a damn thing.