Cooling idea

[KnowledgeSeeker]

If I bring in free cold air from outside and exhaust hot air from the room at the same time as the AC is running it will not take nearly as long to bring the room temp down and it will be a lot cheaper.

Building on this idea I'm thinking of trying the following:

Put the intake and exhaust on a thermostatically controlled outlet so that they only come on when it is cost efficient to bring outside air in. If it's 90 degrees outside i'd rather not bring that air in and try to cool it down. So the power from the cooling outlet of the CHHC-1 will split. One will go to the AC which will always be on. The other will go to a thermostatically controlled outlet that only supplies power to the intake and exhaust when the outside temp is below 70 degrees. Since I'm using a CO2 tank to supply the plants CO2, the outside air isn't required. And yes I will be running the lights at night.

You could get even fancier and use only outside air when it's cold outside with another thermostatically controlled outlet but I'm just working on the first step for now. I also like the idea of using both AC and ventilation to bring the temp down quickly so the cooling period is shorter and the CO2 "marinate" period is longer.

Cons to this setup would be that if your air filter is attached to your exhaust the air inside the room would only be cleansed when the room temp reached a certain level. The room would have to be sealed very well to prevent odor leakage.

This is the thermostatically controlled outlet that I had in mind: [FONT=Arial, Helvetica, sans-serif]Ranco Adjustable Digital Thermostat [/FONT]http://www.littlegreenhouse.com/accessory/controls.shtml

Does anyone have this setup already?

Thoughts on the concept?

 

[KnowledgeSeeker]

Anyone?!?!?!

 

[Mcgician]

I like the sound of it. More sensors equals more control. I just bought a motorized damper to keep the hot outside air from entering the room during the day and plan to run it on a timer. Even better still, I'd have an outside temperature sensor and control device dictating when to open and close it. Since my room has two sources of fresh air, one being an indoor AC vent, I think this is going to help quite a bit.

 

[KnowledgeSeeker]

I like the sound of it. More sensors equals more control. I just bought a motorized damper to keep the hot outside air from entering the room during the day and plan to run it on a timer. Even better still, I'd have an outside temperature sensor and control device dictating when to open and close it. Since my room has two sources of fresh air, one being an indoor AC vent, I think this is going to help quite a bit.

Yah, temp sensor vs. timer is the way to go. The weather changes, the season change, rather than monitor it myself I'd rather have temp sensors do the work so my dumb ass doesn't have to remember to adjust the timers.

Too sources of fresh air huh? That's not a bad idea either. I wish my house had central AC so I could suck cool air into the grow room too.

How much did the motorized damper run you?

 

[Mcgician]

Yah, temp sensor vs. timer is the way to go. The weather changes, the season change, rather than monitor it myself I'd rather have temp sensors do the work so my dumb ass doesn't have to remember to adjust the timers.

Too sources of fresh air huh? That's not a bad idea either. I wish my house had central AC so I could suck cool air into the grow room too.

How much did the motorized damper run you?

I couldn't wait long enough to have it shipped from Ohio for $70 plus shipping, so I bought it locally for $110, plus you need a 24V transformer ($9). It's meant for HVAC applications, not necessarily for 120V grow rooms, lol. If you have the time, hit up these guys. Prices are fair, and the service was impeccable. I bought my chiller from them too.


http://www.plantlightinghydroponics.com/suncourt-10in-motorized-damper-normally-open-p-1967.html

 

[KnowledgeSeeker]

I couldn't wait long enough to have it shipped from Ohio for $70 plus shipping, so I bought it locally for $110, plus you need a 24V transformer ($9). It's meant for HVAC applications, not necessarily for 120V grow rooms, lol. If you have the time, hit up these guys. Prices are fair, and the service was impeccable. I bought my chiller from them too.


http://www.plantlightinghydroponics.com/suncourt-10in-motorized-damper-normally-open-p-1967.html

Ha, ha. Too fuggin funny. I was just lookin at that exact website thinking "they have good prices!" I'll definitely give them a shot.

What kind of chiller do you have and what do you use it for? What kind of setup do you have?

 

[KnowledgeSeeker]

Anyone else have some input on the idea?

 

[Mcgician]

running 2 1000 HPS, 2 3x6 trays, using a top feed rockwool drip system, and using a 10 inch Max Fan coupled with a Phresh filter rated at 1400 CFM. Using Dutch Master Gold line nutes, Hygrozyme, and Drip Clean from from H&G.

 

[KnowledgeSeeker]

running 2 1000 HPS, 2 3x6 trays, using a top feed rockwool drip system, and using a 10 inch Max Fan coupled with a Phresh filter rated at 1400 CFM. Using Dutch Master Gold line nutes, Hygrozyme, and Drip Clean from from H&G.

Nice setup! What kind of reflectors are you running? Are they air cooled?

How do you like the Dutch Master line? How long have you been using it?

 

[YaK]

seal the room, run an AC (I strongly suggest a mini split unit) your CO2 will stay in the room, no need to vent inside air out, or outside in. just use outside air to go through your lights to cool them, then exhaust that air back outside.

For odor in the room just get a can filter, and run it like a scrubber. No odor!

for ebb/flow you dont need any res chillers, especially if you can keep the room at a steady temperature with an AC.

the only problem with my suggestion is cost. about 600 for a split AC, way cheaper if you do a window unit, but I'm not sure if they exchange air from the room.

 

[potlike]

I said it in another post I'll say it again... Swamp cooler then you can run it even when it is hot outside.

To demonstrate how a swamp cooler works take your finger and blow on it? Hot/warm/temperate right? Now take your finger put it in your mouth take it out and blow on it? Your finger gets a little cooler because of the moisture.

Now have a humidistat set to run whenever humidity is fine and you can bring cool air from outside in even when it's in the 90's.


-potlike

 

[KnowledgeSeeker]

seal the room, run an AC (I strongly suggest a mini split unit) your CO2 will stay in the room, no need to vent inside air out, or outside in. just use outside air to go through your lights to cool them, then exhaust that air back outside.

the only problem with my suggestion is cost. about 600 for a split AC, way cheaper if you do a window unit, but I'm not sure if they exchange air from the room.

Thx for the advice Yak.

I purchased a dual hose AC unit (see journal here: https://www.rollitup.org/grow-journals/232930-first-grow-3000w-ebb-gro.html ) so that's what I've got to work with now.

I know that venting isn't required when using CO2 but it seems like it would be more efficient to use free cold outside air rather than having the AC do all the work. CO2 is cheaper than electricity and with my CHHC-1 controller doing it's job, CO2 levels would only be down during venting which would only happen as required to maintain temp.

 

[YaK]

Thx for the advice Yak.

I purchased a dual hose AC unit (see journal here: https://www.rollitup.org/grow-journals/232930-first-grow-3000w-ebb-gro.html ) so that's what I've got to work with now.

I know that venting isn't required when using CO2 but it seems like it would be more efficient to use free cold outside air rather than having the AC do all the work. CO2 is cheaper than electricity and with my CHHC-1 controller doing it's job, CO2 levels would only be down during venting which would only happen as required to maintain temp.

I read your journal after this thread. Great journal by the way.

I hate those kind of ACs... they take up floorspace, and the exhaust tube is usually hot to the touch. I ran one once, and insulated the exhaust, but it was kind of a pain in the but.

I live in california, so it's not often that the air outside is cold.

If you have cold air outside, and a controller, then I think you're on the right path.

I have a greenhouse controller as well that regulates the CO2 ppms and turns on exhaust when temps or humidity is too high, and of course, it shuts off the CO2 when the exhaust is on. It's a great piece of equipment to have if you're not running a sealed room.

I look forward to following your journal!

 

[KnowledgeSeeker]

I said it in another post I'll say it again... Swamp cooler then you can run it even when it is hot outside.

Now have a humidistat set to run whenever humidity is fine and you can bring cool air from outside in even when it's in the 90's.

-potlike

Thank you for the suggestion potlike. My parents live in New Mexico and they have a swamp cooler for their house so I am familiar with the technology. I'm hesitant to run one in my grow room though. The de-humidifier that I have now runs quite often and it's only week 4 and the plants are small (see journal here: https://www.rollitup.org/grow-journals/232930-first-grow-3000w-ebb-gro.html ). 4 weeks from now I'm thinking the dehumidifier will be running 24/7 to keep the humidity down. The de-humidifier generates heat. More heat than I expected. I wish I could vent that outside too. Anyways, I don't want to compound a humidity/de-humidifier-heat issue by using swamp cooler. Thanks for the advice though. I appreciate it.

 

[potlike]

If you are familiar with the technology then you should know that it CAN act as a dehumidifier as well.

There are two kinds of swamp/evap coolers. You don't want single stage swamp coolers, but two stage swamp/evap coolers can take relative humidity from 70% down to 50% by pre cooling the air. Then when released the 50% relative humidity will react w/ ambient humidity in the room. Since marijuana likes ~50-60% rh roughly for flowering it is a win win situation.

As for the heat generated from the dehumidifer I would suggest looking into a peltier device. While having low efficiency rates with a proper heatsink and exhaust system you can drop your temperature several degrees. Depending on the physical construction of your dehumidifier it may require some creativity.

Feel free to research the above info if you are unsure and you are welcome.


-potlike

 

[KnowledgeSeeker]

If you are familiar with the technology then you should know that it CAN act as a dehumidifier as well.

There are two kinds of swamp/evap coolers. You don't want single stage swamp coolers, but two stage swamp/evap coolers can take relative humidity from 70% down to 50% by pre cooling the air. Then when released the 50% relative humidity will react w/ ambient humidity in the room. Since marijuana likes ~50-60% rh roughly for flowering it is a win win situation.
-potlike

Oooohhh! I didn't know there were two kinds of swamp coolers. That is very helpful. I'll do some more research on it. Thanks again for your input.

 

[KnowledgeSeeker]

I read your journal after this thread. Great journal by the way.

Thanks!

I hate those kind of ACs... they take up floorspace, and the exhaust tube is usually hot to the touch. I ran one once, and insulated the exhaust, but it was kind of a pain in the but.

What do you use for cooling now?

I live in california, so it's not often that the air outside is cold.

If you have cold air outside, and a controller, then I think you're on the right path.

I live in Northern Cali. I run the lights at night and the low temp for my area tonight is 50 degrees. Good for cooling a grow room.

I have a greenhouse controller as well that regulates the CO2 ppms and turns on exhaust when temps or humidity is too high, and of course, it shuts off the CO2 when the exhaust is on. It's a great piece of equipment to have if you're not running a sealed room.

I agree. Which controller do you have?

I look forward to following your journal!

Thanks, I'm trying to keep it current. We'll see how that goes...

 

[YaK]

Thanks!



What do you use for cooling now?

I use a mini split ductless system like in the link below, but I have an 1800 BTU w/ inverter (important for energy savings)

http://cgi.ebay.com/DUCTLESS-MINI-SPLIT-AC-CONDITIONER-SYSTEM-AND-HEAT-PUMP_W0QQitemZ280393661944QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item4148c3bdf8&_trksid=p3286.c0.m14#ht_6452wt_1185

I live in Northern Cali. I run the lights at night and the low temp for my area tonight is 50 degrees. Good for cooling a grow room.

no doubt!

I agree. Which controller do you have?

I use this one:

Thanks, I'm trying to keep it current. We'll see how that goes...

There's always a lot to do, and keeping a current journal can be tedious, but you can get some good help along the way. Keep up the good work!

 

[KnowledgeSeeker]

I use a mini split ductless system like in the link below, but I have an 1800 BTU w/ inverter (important for energy savings)

http://cgi.ebay.com/DUCTLESS-MINI-SPLIT-AC-CONDITIONER-SYSTEM-AND-HEAT-PUMP_W0QQitemZ280393661944QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item4148c3bdf8&_trksid=p3286.c0.m14#ht_6452wt_1185

Do you have an 1800 BTU or 18000 BTU system? Did you have to have the system installed by a professional or were you able to do it yourself? Did you notice a dramatic difference in your electricity bills after the upgrade?

I use this one:

I checked the specs and that controller looks SWEEEET! Do you have any likes/dislikes about it?

 

[potlike]

Did you have to have the system installed by a professional or were you able to do it yourself? Did you notice a dramatic difference in your electricity bills after the upgrade?



I checked the specs and that controller looks SWEEEET! Do you have any likes/dislikes about it?

Here you go

1000w= 3412.1416 BTU

Use BTU as your variable so 1BTU= 1000w/3412.1416 =.293...... we'll round off now multiply that x 1800 ~ 527 watts

Now because it isn't completely efficient there will be some additional wattage used. However ~530-550w is considerably good for AC even though I've designed specs about half of that. Many ptac units that I would compare this device to use around 1200watts of electricity for cooling and around 3000 watts for heating.

All in all a good device, I'm just not money rich and I love building things so I would build it myself. If you want to purchase their unit I'm sure you could learn alot from instructables and youtube, you'd be surprised how many people before you have done it and what you can learn from the internet.


-potlike