| We've all heard that there is no such thing as a | | | | multi-outlet adapter and plug them into your CO2 |
| 'free lunch'; well the process described in this | | | | sequencer along with your CO2 generator or CO2 |
| article may be as close to one as you get. Most | | | | tank regulator using a 3 outlet adapter. |
| of us already know the benefits of CO2 | | | | If the pipes are far from the outside wall or roof |
| enrichment for photosynthesis. To maximize | | | | there may be inline duct booster fans. If the grow |
| indoor growing and greenhouse potential, CO2 is | | | | room is not getting flow through the new duct, a |
| supplemented to maintain an approximate level of | | | | inline duct booster fan may be needed, especially |
| 1500 ppm, this can require frequent trips to an | | | | if there is one used on the original duct that |
| industrial gas supplier and/or a lot of propane or | | | | exhausts to the outside past the new "Y" section |
| natural gas use, and related costs. It is ironic that | | | | from the appliance. If you add a duct booster fan, |
| many indoor farmers are exhausting CO2 to the | | | | wire it or plug it in together with the dampers, |
| outdoors from home heaters and hot water | | | | they will then power on and off together. Many |
| heaters while simultaneously releasing or | | | | furnaces will have an adequate exhaust blower so |
| generating CO2 for an indoor grow room or a | | | | an additional duct booster fan will not be |
| greenhouse. | | | | necessary. Keep an eye on any booster fans (if |
| Propane and Natural gas burn clean enough that | | | | any) on the original duct between the "Y" junction |
| small non-vented gas devices have been | | | | and the outside, there is a chance they could |
| approved for indoor use. These gas burning | | | | overheat if running when the damper to the |
| devices all use oxygen (in the air) to burn the gas, | | | | outside is closed. |
| resulting in the by-products of CO2, H20 | | | | Once this is setup, when your CO2 sequencer |
| (humidity), and heat (Reusch). Exhaust from gas | | | | determines it's time to add CO2 to the room and |
| appliances can provide 3 essential conditions for | | | | switches power on, the exhaust damper to the |
| maximized growth: humidity, temperature, and | | | | outside will close and the damper to the grow |
| CO2 level. Most heat from the exhaust is | | | | room will open; resulting in the furnace's or hot |
| removed by the heat exchanger of the furnace | | | | water heater's exhaust being diverted into the |
| or water heater; resulting in mildly warm exhaust. | | | | grow room. The CO2 generator or release |
| Photosynthesis for many plants, including | | | | regulator will be working also, this way the room |
| marijuana, in a CO2 enriched environment,is most | | | | is guaranteed to always have just the right |
| efficient around 85 degrees F. | | | | amount of CO2 even if the furnace or water |
| If a large gas heater's exhaust is diverted into the | | | | heater is not currently in use. When the proper |
| grow area, there is great potential for all the | | | | level is reached and the sequencer powers off, |
| oxygen to be burned up or displaced, as well as | | | | the damper leading into the grow room will close |
| CO (carbon monoxide accumulation), resulting in | | | | and the damper in the duct leading to the outside |
| toxic air conditions. With proper equipment, the | | | | will reopen. All exhaust at this point will vent |
| CO2 from your gas furnace and/or water | | | | outside until the room needs more CO2. |
| heater's exhaust can be safely used to | | | | For safety, be sure all circuits and/or outlets are |
| supplement the CO2 used in your grow room. | | | | supplying no more than 80% of their rated load in |
| This will save time and money, make the plants | | | | watts, and are properly wired. Also, be sure to |
| grow great, reduce fuel use, and dramatically | | | | secure duct well. The 200°F rated duct tape |
| reduce the amount of 'Greenhouse' gasses | | | | holds up better than the regular (for connecting |
| released into the environment. Using this | | | | duct sections). |
| technique, you will help prevent global warming | | | | If you are diverting the hot water heater exhaust |
| while optimizing growing conditions. The key to | | | | for this CO2 enrichment supplement, you can |
| doing this safely and effectively is to divert | | | | further take advantage of this setup by timing |
| enough exhaust from your gas appliance into your | | | | showers, dishes and laundry, as the lights come |
| grow area to maintain a CO2 level of 1500 ppm, | | | | on (time that enrichment equipment runs the |
| and have additional exhaust directed outside. | | | | most) and during the light cycle in general. |
| "The Occupational Safety and Health | | | | Using this system, farmers will find they make |
| Administration (OSHA) and the American | | | | less trips to get propane or CO2 tanks filled, and |
| Conference of Governmental Industrial Hygienists | | | | are spending less money, while the levels in the |
| (ACGIH) have set workplace safety standards of | | | | grow room remain the same. |
| 5,000 ppm" and very high CO2 levels can cause | | | | This addition to an enrichment system will also |
| undetectable asphyxiation when O2 in the blood is | | | | reduce the volume of CO2 released into the |
| replaced by the CO2 (Minnesota Department of | | | | environment from the house or business. The |
| Health). Keep a CO (carbon monoxide) detector in | | | | CO2 diverted to the room is used by the plants |
| the grow room for safety in case equipment | | | | during photosynthesis, further reduces the gas |
| malfunctions! Do not attempt this project if you | | | | appliance's CO2 release into the environment. |
| use oil or kerosene heat, which do not burn | | | | Using this system, the room will reach the desired |
| cleanly! | | | | CO2 level quicker, and fluctuate less, further |
| The trick to tapping into this source of unused | | | | enhancing growth. |
| CO2 from gas furnace and water heaters is | | | | Works Cited List: |
| power dampers. A power damper is a duct | | | | Minnesota Department of Health |
| section with a flap that opens and closes the flow | | | | This page, located on the Minnesota Department |
| through the duct and is powered by electricity. | | | | of Health's website, is a good source to show the |
| Some dampers close with current applied and | | | | adverse health effects high levels of C02 will |
| others are designed to open. Most dampers are | | | | cause. As best as I can tell, this site is run by the |
| low voltage so the right size transformer must be | | | | State government. The information on this page |
| wired inline to the damper; there are some | | | | is consistent with other sources also describing |
| 110volt dampers. Quality dampers will seal much | | | | the harmful health effects caused by too much |
| better than cheap dampers. This simple addition to | | | | CO2 in air. This page, while short, clearly presents |
| a CO2 enrichment system will pay for itself many | | | | figures and dangers, agreed upon by government |
| times over (especially with today's fuel prices) and | | | | scientist, that are associated with high CO2 levels. |
| reduce house or business emissions into the | | | | The statement, "At very high levels, 30,000 ppm |
| environment, making your project 'greener'. It is | | | | and above, CO2 can cause asphyxiation as it |
| necessary to have a CO2 levels monitor hooked | | | | replaces oxygen in our blood." clearly |
| to a controller (sequencer) to tell the dampers (by | | | | demonstrates the potentially fatal condition that |
| applying power) when CO2 is needed and when | | | | elevated CO2 levels can cause. |
| the threshold has been reached. You can still use | | | | "Carbon Dioxide (CO2)" Minnesota Department of |
| your controller to run your CO2 generator and or | | | | Health. Mar. 2004. |
| regulator. | | | | 27 June 2005 |
| Find the exhaust pipe of your gas furnace or hot | | | | Reusch, William. "Reaction of Alkanes" Michigan |
| water heater. These devices should already be | | | | State University |
| properly vented. Turn off your gas appliance while | | | | This page clearly describes the physical process of |
| working on this. Disconnect (or cut open) a | | | | propane combustion. After reviewing a dozen |
| section of duct where it will be closest, with least | | | | sources of propane and natural gas combustion, I |
| bends, to tap in and route a new duct to the | | | | found this page to have most precise, in-depth |
| grow area. The few items needed can be found | | | | yet understandable descriptions of the potential |
| at most heating supply stores. If you can not find | | | | reactions of propane combustion. Although the |
| matching dampers for the size and type of duct | | | | article cites no references for the information it |
| that you have, you may have to convert the | | | | contains, the information is consistent with |
| duct to a size or type that you can find dampers | | | | common knowledge and other reference |
| for. Using a "Y" connector and a power damper | | | | materials and is on the Chemistry Department's |
| that closes when power is added, hook up inline | | | | web site of the Michigan State University. By |
| with the duct running to the outside. For smooth | | | | showing the structural formulas for the reactions |
| flow, install "Y" so exhaust comes in the 'bottom' | | | | mentioned along with clear reasoning |
| of the "Y" duct section. Now take the damper | | | | demonstrating why the reactions may differ, this |
| that opens when power is applied, attach it to the | | | | source will allow a reader of my essay to |
| other "Y" opening. Run a duct from this 'power | | | | understand what products can be created by |
| open' damper into the grow area above the | | | | propane combustion. This article shows how CO2 |
| plants, since CO2 is heavier than air; but you | | | | and H2O are the direct products obtained by the |
| probably already know this. Now all you have to | | | | burning of propane when sufficient O2 present. |
| do is either wire the dampers together or use a | | | | Reusch, William. |