Temp control issue

Flowki

Well-Known Member
The idea was to oversize in/out fans for summer to reduce noise and over using motors. The short falling was that at idle speed the temps are too low in winter months, creating needless heating waste.

Would you plug the fan controller into a timer during winter to shut off 15 min after lights off? (de-hue in use).

Or, plug the fan speed controller into a thermostat that will cut off airflow when temps drop below 68?.

The first choice seems like the most economical but how much do they need airflow lights off?. The second option, I don't know if stop/starting the fan speed controller and fans is going to be good on the motors etc.. although it would seem the most optimal option aside from that.
 

stoned-monkey

Well-Known Member
lots of options.
thermostat would be the best option imo.
fans on timers with lights will be fine (as long as humidity isn't too high)
or buy low volume fans, duct boosters work fine for me, I can take my tent into the 50'S if I wanted to with just duct fans. they are cheap on amazon too.
 

OldMedUser

Well-Known Member
High Flowki

There's no real need for airflow in the dark. Still want your internal air movement to be going but don't need to bring in fresh air or exhaust any air.

RH goes up after lights out because the temp drops and even tho the moisture may be the same the relative humidity reads higher as it's relative to the air temp.

If you are in late flowering tho the RH is certainly important even in the dark. You'll need to have your RH switch set low and then of course your exhaust is going to cycle. It's a balancing act I have to go thru too. I live way up north in Alberta and the RH is brutally low in the depths of winter and doesn't get all that high in summer either.

I stick to my old magnetic HID lights because they work so good and I need the heat. Invest in a bunch of LEDs and I'd be losing money all over as the heater would have to be kicking in all the time to keep the temps up around 75F.

I just have a 6" inline fan and it was running half speed but is starting to die on me so have it run full speed now when it kicks in. Got to have fresh air or the plants stall when they run out of CO2.

You might want to get a duct fan you can either connect into your existing system with a "Y" adapter and put cheap back-flow flaps in to be able to have either fan go and not blow back thru the other. Or a separate exhaust port for a smaller fan that is just connected to a humidity switch like you get for bathrooms. Then it would blow out a little air and keep the RH down as needed. Heater would still kick in but not as often and not for long.

Fine tuning the environment is important and hard to do unless you have deep pockets and can get the best gear to do it. I sure don't have deep pockets so have to find work arounds that actually work.

Good luck and good growing!

:peace:
 

Flowki

Well-Known Member
High Flowki

There's no real need for airflow in the dark. Still want your internal air movement to be going but don't need to bring in fresh air or exhaust any air.

RH goes up after lights out because the temp drops and even tho the moisture may be the same the relative humidity reads higher as it's relative to the air temp.

If you are in late flowering tho the RH is certainly important even in the dark. You'll need to have your RH switch set low and then of course your exhaust is going to cycle. It's a balancing act I have to go thru too. I live way up north in Alberta and the RH is brutally low in the depths of winter and doesn't get all that high in summer either.

I stick to my old magnetic HID lights because they work so good and I need the heat. Invest in a bunch of LEDs and I'd be losing money all over as the heater would have to be kicking in all the time to keep the temps up around 75F.

I just have a 6" inline fan and it was running half speed but is starting to die on me so have it run full speed now when it kicks in. Got to have fresh air or the plants stall when they run out of CO2.

You might want to get a duct fan you can either connect into your existing system with a "Y" adapter and put cheap back-flow flaps in to be able to have either fan go and not blow back thru the other. Or a separate exhaust port for a smaller fan that is just connected to a humidity switch like you get for bathrooms. Then it would blow out a little air and keep the RH down as needed. Heater would still kick in but not as often and not for long.

Fine tuning the environment is important and hard to do unless you have deep pockets and can get the best gear to do it. I sure don't have deep pockets so have to find work arounds that actually work.

Good luck and good growing!

:peace:
lots of options.
thermostat would be the best option imo.
fans on timers with lights will be fine (as long as humidity isn't too high)
or buy low volume fans, duct boosters work fine for me, I can take my tent into the 50'S if I wanted to with just duct fans. they are cheap on amazon too.
So to clarify this. Using in/out take fans plugged into a fan speed controller to maintain upper temp is working fine. The lowest idle speed that the fan controller goes down too (10% I believe) is dropping temps too much in winter. Plugging the fan speed controller into a thermostat to shut off the controller>fans if temps drop below 68f will be ok?, with little to no damage to the fan speed controller or fans. A dehumidifier is in use to maintain rh.

Btw any ideas on such a thermostat brand to achieve this? and is it robust enough to handle such a job (8" fans into a volt step controller). The thermostats I have seen and used turn something on when too cold, not off.
 

stoned-monkey

Well-Known Member
I would use the thermostat and either leave on high or remove the fan controller. I dont use thermostats in my grow so could not recommened any one. Amazon has them, grow stores would have them. I am pretty sure titan makes one.
 

Flowki

Well-Known Member
I would use the thermostat and either leave on high or remove the fan controller. I dont use thermostats in my grow so could not recommened any one. Amazon has them, grow stores would have them. I am pretty sure titan makes one.
Removing the fan controller isn't an option as the fans are designed to be used with one. I'll look into titan thnx.
 

Flowki

Well-Known Member
I've had a look around amazon and I found this

It's designed for aquarium or brewing temp/cooling control but would do the exact job I need. Prob is it's only rated up to 2200W and the heater alone is 2k. Any idea of such a controller that is more fit for purpose?.
 

stoned-monkey

Well-Known Member
just plug your heater into the controller and keep your fans on (separate outlet).
a lot of heaters have settings too, like high/low, in which the heater will consume less power, example high=2000watts low=1000watts. so if your heater has that capability you can just leave it on a lower setting.
or buy a heater with a thermostat, which probably wont be to much more then the controller.
 

Flowki

Well-Known Member
just plug your heater into the controller and keep your fans on (separate outlet).
a lot of heaters have settings too, like high/low, in which the heater will consume less power, example high=2000watts low=1000watts. so if your heater has that capability you can just leave it on a lower setting.
or buy a heater with a thermostat, which probably wont be to much more then the controller.
I've ran over these options. The airflow needs to be switched on/off and more efficiently if thermostatically controlled. 2000W with airflow off will maintain lights off temps but not comfortably, it's minus outside.
 

stoned-monkey

Well-Known Member
idk, two thermostats then? I feel ya its -9c where I am at. you will get it figured out. how cold is it getting in your grow?
 
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Flowki

Well-Known Member
idk, two thermostats then? I feel ya its -9c where I am at. you will get it figured out. how cold is it getting in your grow?
At idle speed with heater always on I've not been able to get over 75 on, down to 58 off. So it's been a case of manual micro management of airflow but it's a losing battle. I don't regret the fan sizes for summer but the winter has been a real oversight ;/. Yeah, think I'll use the linked unit for the airflow and continue with a normal thermostat for heating. Don't seem safe to use that linked item for both, unless you know of a better unit, would prefer that as the wired therm probe is a lot better.
 

stoned-monkey

Well-Known Member
you know if you're handy with electricity and have the money you can install some thermocouples, humidity probes(optional) and a controller/read-out that flips some solid state relays. this would be like a industrial/commercial type of temp. control. it will allow you to control multiple circuits at a time, meaning it can be expanded upon for all sorts of loads.
 

Flowki

Well-Known Member
you know if you're handy with electricity and have the money you can install some thermocouples, humidity probes(optional) and a controller/read-out that flips some solid state relays. this would be like a industrial/commercial type of temp. control. it will allow you to control multiple circuits at a time, meaning it can be expanded upon for all sorts of loads.
Unfortunately my talents don't over lap with electrics ;/.. and I will always remain hesitant to diy learn it due to the punishment for error.
 

nevergoodenuf

Well-Known Member
On my winter setup, I add CO2 and use the dehumidifier to keep my temps up. I only use hyperfans (comes with speed controller) for my intake and exhaust hooked to a temp/humid controller. I have a simple plug in CO2 controller and a tank. At the moment I have 2500w of COB leds in the room and the exhaust only turns on if the temps go above 86*f or if the humidity spikes over 60rh. If more heat is needed, you could use a CO2 burner instead. This setup has been the most efficient way I have found for my room.IMG_20170630_065249905.jpg CO2 controller I use is in the pic.
 
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