CANNABIS TEMPERATURE CONTROL SYSTEMS
Indoor Grow Facilities - Copyright Protected, Pre-Priority Norlock Refrigeration
Skid Pack Chiller System - can be used as an alternative if Natural Gas is not available
Water source heat pump “Eco-Cute”
Industrial and commercial hot water and chilled water supply
unimo WW performs the functions both of Boiler and Water Chiller all in one machine.
Both 149 - 194 ºF hot water and 44 ºF chilled water can be supplied simultaneously.
Effective Utilization of Unused Waste Heat
Unused low temperature waste heat from the plant or cooling water can be used as heat source.
Reduction of Existing Water Chiller Power Consumption
Performance of existing water chiller is increased and also its power consumption is decreased by utilizing it's cooling water as a heat source.
Equalization of Electricity Power Load
Storing hot water and chilled water using off peak tariff of electricity, the peak cut of electricity demand can be achieved.
Easy installation with boiler and water chiller in one compact cabinet.
Cannabis Adiabatic Cooling System
Norlock has developed combined AC systems for Cannabis grow system’s to save electricity.
Here is one example:
With the use of adiabatic fluid cooler’s and the staging 2 chillers, you can reduce power consumption.
For the Kelowna, BC area, 60% of the hours per year have an ambient temperature below 65°F (18°C), which would not require more than a standard fluid cooler to meet temperature. An additional approximate 20% of the year could provide the cooling required with an adiabatic control on the same fluid cooler to provide the required 65°F (18°C) wet bulb condition.
The result would be an estimated 45% electrical savings of the total hours per year energy saving’s.
Free-cooling by using mother nature.
The free-cooling option delivers optimal performance by minimizing compressor operation when outdoor air temperatures are low enough to assist in cooling the chilled fluid loop. Free-cooling is built with all aluminum flat channel dry cooler exchanger, installed in parallel with refrigerant micro-channel condenser coil, and a water valve to control the free-cooling capacity. This option is intended for applications with glycol on the chilled loop. The inhibited glycol solution should be selected at desired concentration to insure adequate inhibitor content. The glycol solution requires an inhibitor package to be carefully chosen and maintained with the aid of a qualified water treatment specialist to protect the mixed metal system.
By using a water cooled chiller in conjunction with an Adiabatic Fluid Cooler significant energy savings can be realized. The summer months of May, June, July, August, September would only benefit during the later night time hours, leaving 7 months of the year where the majority of the cooling power requirement could be handled by the Adiabatic Fluid Cooler. For the 5 summer months reduced chiller horse power and therefore power requirement would be realized with the adiabatic fluid cooler providing the closed loop for the water cooled chiller.
Adiabatic Fluid Coolers save 80% of the water consumption that a closed or open cooling tower would require, and do not require any water treatment for a water reservoir. They will also saving more than 45% of the water consumption that a media type fluid cooler would require, and do not require any water treatment for a water reservoir.
Adiabatic Fluid Coolers may require water treatment for the feed water if it is not clean or it is hard.
Wet bulb temperature during day time high
Wet bulb temperature during day time low
Maximum Wet bulb for adiabatic fluid cooler to provide cheat rejection from the closed glycol loop
Wet bulb required for Water Cooled Chiller closed loop heat rejection
Note the desiccant can be fired using Natural Gas at 1/3 the cost of electrically driven mechanical systems
Health, Safety and Hygiene for customers is essential to Norlock which is clearly reflected in the design of the desiccant wheel (rotor). Our rotors are continuously being tested independently and have most recently been proven by The Swedish Institute for Food and Biotechnology to have both bactericidal and fungicidal properties.
What Is The Difference Between Desiccant and Mechanical Dehumidification?
DESICCANT OR REFRIGERANT?
Dehumidifiers remove moisture from the air. There are two main types of dehumidifier technology that do this: Desiccant and Mechanical (refrigerator coil technology).
Desiccant dehumidification works by passing air through a rotating desiccant wheel to exact moisture from the air. Desiccants such as silica gel naturally absorb moisture - that's why you'll find little packets of silica gel in new shoes or electronic goods. As the wheel rotates, a small portion of the rotor is used to reactivate the wheel. In this portion the desiccant is heated so the the moisture is released and is then ducted out from the dehumidified space.
Rinnai Demand Duo 2 Hybrid Water Heating System Now Available!
The Rinnai Demand Duo 2 Hybrid Water Heating System comes equipped with two CU199 tankless water heaters with freestanding rack connected to a 119-gallon storage tank, offering built-in redundancy and storage for high spike draws-eliminating the need to purchase multiple tank water heaters.
Featuring Rinnai’s DuoSmart Tank Technology with pre-installed Recovery Pump, Controller, and Electrical junction box, Demand Duo 2 ensures reliability and maintains consistent temperature with lower acquisition, operating and life cycle costs.
Available for order NOW!
Rinnai on - demand water heating systems
Things To Consider - HVAC Sysems
Many specialized manufacturers point out that the HVAC loads in cannabis facilities are far larger than in normal HVAC applications. Although they are correct, experience has taught us that we can account for those heavy-duty loads through careful equipment selection and design within the semi-custom equipment product range.
Standard equipment is well-understood in the HVAC industry and requires less specially trained personnel to perform maintenance. This can have a significant effect on operating expenses.
Specialty cannabis equipment often comes with opaque and proprietary control systems which require manufacturer intervention in order to make changes. The manufacturers are seldom local and may not be available when needed.
Specialty cannabis equipment may, in some cases, be more costly than a simple, carefully designed system that uses standard equipment.
Some specialty cannabis systems rely on fan coil units hung in the grow rooms. However many grow rooms are intended to be clean spaces with limited access. Suspending equipment in these rooms is inappropriate for the following reasons:
The fan coils are difficult to clean
It is difficult to protect the grow room from contaminants that can be generated on coil surfaces or in the drain pan
Maintenance personnel will need to enter the grow room to perform maintenance on the equipment, introducing contaminants and reducing security. Also, the time required to pass maintenance personnel through security and gowning procedures will increase the cost of all maintenance operations.
GMP compliance will not be possible.
HVAC and CO2 Cannabis Room SENSOR
The horticulture sensor series uses a highly accurate and reliable dual-channel, non-dispersive infrared (NDIR) sensor to monitor CO2, a precision thermistor to monitor temperature and a thermoset polymer based capacitance sensor to measure humidity levels.
Features include an LCD for configuration and monitoring, various output signal types, optional relays for alarm indication and field replaceable sensors.
Power Supply..........................24 Vac/dc ±20% (non-isolated half-wave rectified)
Consumption..........................75 mA max @ 24 Vdc, 125 mA max @ 24 Vac
Protection Circuitry..............Reverse voltage protection, overvoltage protected
Operating Conditions.........-10 to 50°C (14 to 122°F), 5 to 95 %RH non-condensing
Storage Conditions..............-30 to 60°C (-22 to 140°F)
Wiring Connections.............Screw terminal block (14 to 22 AWG)
Country of Origin:.................Canada
Dimensions:.............................130mm W x 130mm H x 75mm D (5.12” x 5.12” x 2.95”)
Size.........................................35mm W x 15mm H (1.4” x 0.6”)
alpha-numeric 2 line x 8 characters
Backlight..............................Enable or disable via menu or network
Range..........................................0 to 50°C (32 to 122°F)
RELATIVE HUMIDITY SIGNAL
Sensor.........................................Thermoset polymer based capacitive
Range..........................................0 to 100 %RH
Response Time.......................15 seconds typical
Stability......................................±1 %RH typical @ 50 %RH in 5 years
Protocol.....................................MS/TP, 2-wire RS-485
Baud Rate..................................9600, 19200, 38400, 57600, 76800, or 15200
Address Range.......................0 to 127
OPTIONAL CO2 SIGNAL
Measurement Type..............Dual wavelength, non-dispersive infrared (NDIR), diffusion sampling
Measurement Range..........0 to 5000 ppm
Standard Accuracy...............±50 ppm + 3% of reading
Pressure Dependence........< 1% of reading / kPa
Response Time.......................2 minutes (T90)
Sensor Life Span....................> 10 years
OPTIONAL RELAY OUTPUTS
Contact Ratings.....................Form C (NO + NC), 2A @ 140 Vac, 2A @ 30 Vdc
Setpoint + Hysteresis..........Programmable via menu or network
Time Delay...............................Programmable via menu or network
It is analog outputs , in this case 4-20 mA and there are options for 1 or 2 relays .
Suggested HVAC Temps & Humidity
Seedlings and clones like RH levels of 65–80%. Remember, these young, fragile plants have weak root systems. By increasing humidity levels, you’ll allow them to take up more water from the environment and focus on developing strong roots. At this early stage, you’ll want to keep temperature levels at around 25°C during the day, and around 21°C at night (77°F and 70°F, respectively).
Vegetative plants, on the other hand, tend to prefer moderate humidity levels. There’s no exact figure to follow here, but you’ll want to stick somewhere between 55–70% depending on the strain. Temperatures should sit between 22–28°C (71–82°F) during the day and roughly 18–24°C (64–75°F) at night. Vegetative plants have strong root systems and will absorb more water from the soil, which is why most growers drop humidity levels slightly during this stage.
At the early flowering stage, most growers agree that plants benefit from lower humidity levels. Again, there’s no ideal figure to aim for, but many will stick between 40–50%, occasionally pushing to roughly 55%. You’ll also want to drop temperatures to about 20–26°C (68–78°F).
During the late flowering stage, try to drop humidity to about 30–40% and keep temperatures around 18–24°C (64–75°F) during the day, followed by slightly cooler nights (16-20C in the last few nights).
Air Movement For Marijuana Growing
Air ventilation and circulation is one of the essential parts of healthy marijuana growing indoors. Many times, people who are start marijuana growing indoors overlook air ventilation/circulation and have a small harvest or even none at all.
Fresh air is the least expensive and most essential component required for indoor marijuana growing. There are three factors that affect air movement plant: 1) stomata, 2) ventilation, and 3) circulation.
Stomata are microscopic pores on leaf undersides, which are similar to an animal’s nostrils, where they breathe in and out oxygen and carbon dioxide. In cannabis, oxygen and carbon dioxide flows are regulated by the plants’ stomata.
The more plants and larger they are, the fresher CO2 rich air they will need for marijuana growing to be successful. Stomata are easily clogged by dirt from pollutants in the air and by sprays being applied to the leaves. To keep plant foliage clean, spray them down with water
Plants use all of the CO2 around the leaf within a few minutes. If there is no CO2 to replace it, CO2 depleted air creates a dead air zone around the leaves. If air is not actively moving, it stifles stomata and air around leaves stratifies.
With warm air staying up by the ceiling and cool air down by the plant roots, having air circulating will help to break this stratification. This is why having air circulating within the room helps plants.
With proper air circulation in a room, it can help prevent harmful pest and fungus attacks, with the plants constantly being hit by burns of air movement.
It is always good practice to make your marijuana growing room have negative pressure. Negative pressure is when there is more air being pulled out of the room that is being delivered to the room, causing the door to automatically shut.
Usually a ratio of 1:4 is used, 100 CFM incoming and 400 CFM outgoing. By having negative pressure air does not have a chance to leak out the intake and release odors outdoors (if running constantly), while also helping CO2 (Carbon Dioxide) enhancement within indoor grows to keep the CO2 in the room.
Larger ducting such as 8, 10, 12-inch (20, 25, 30 cm) is ideal for moving larger volumes of air when needed, though if your marijuana growing operation is smaller and has fewer heat issues, you can use either 4 or 6 inches ducting.
It is often recommended to pipe air to the plants via flexible ducting. This will allow the fresh air to pour down onto the
plants and refresh them with oxygen and carbon dioxide. Be sure that the fresh air is neither too hot nor too cold; many growers will duct air from a crawlspace or under a patio to bring in cool air.
Vapor Pressure Deficit
Humidity is HUGE when it comes to growing plants. An important milestone in becoming a competent and responsive grower is developing an understanding of what humidity is, how plants respond to it, and how you can manage and manipulate it.
Firstly, let's make sure we're all on the same page. When we speak of the "humidity" of or in the air we are basically referring to the amount of water in the air. "In the air?" What do we mean? Well, water can only truly stay in the air when it is in gas form - aka "water vapor". We're not talking about tiny droplets of water in the air here (e.g. fog or mist.)
Unsurprisingly, temperature plays a crucial role when it comes to humidity. The warmer the air, the more water vapor it can potentially hold. As the amount of water air can hold constantly changes with temperature it can be difficult to get a handle on what we need to measure. Fortunately, an answer comes in the form of the concept of "Relative Humidity" (RH) - this is a measurement in terms of percentage, of the water vapor in the air compared to the total water vapor potential that the air could hold at a given temperature.
So, when we say there's a relative humidity of 50% - we mean "At this specific temperature, the air is carrying half the potential water vapor possible."
The Effect of Relative Humidity on Your Plants
RH can be easily measured using digital or analogue meters called "hygrometers." They are available for around $15 at your local indoor gardening store. But what do the readings mean for your plants?
Turns out-they mean a great deal! While many novice growers focus solely on keeping temperature in range, many take their eye off the ball as far as RH is concerned-perhaps because they don't fully understand what it is or how to manipulate it to their advantage.
Have you ever been to Florida in July? You'll know that it's not just the heat that's oppressive, it's the humidity! You feel constantly wet with sweat - the whole place feels like a sauna you can't escape from! (Sorry Floridians!)
RH has an ever more direct effect on plants. Plants need to "sweat" too - or rather, they need to transpire (release water vapor through their stomata) in order to grow.
The amount of water plants lose through transpiration is regulated, to a point, by opening and closing their stomata. However, as a general rule, the drier the air, the more plants will transpire.
All gasses in the air exert a certain "pressure." The more water vapor in the air the greater the vapor pressure. What does this mean? Well, in high RH conditions (think of Florida again) there is a greater vapor pressure being exerted on plants than in low RH conditions. From a plant's perspective, high vapor pressure can be thought of as an unseen force in the air pushing on the plants from all directions. This pressure is exerted onto the leaves by the high concentration of water vapor in the air making it harder for the plant to 'push back' by losing water into the air by transpiration. This is why with high RH plants transpire less. Conversely, in environments with low RH, only a small amount of pressure is exerted on the plants' leaves, making it easy for them to lose water into the air.
What is Vapor Pressure Deficit (VPD)?
Okay, so now that you have RH firmly implanted into your conceptual map, we move on to Vapor Pressure Deficit or VPD. As implied by the word "deficit" we're talking about the difference between two things. In this case, it's the difference between the theoretical pressure exerted by water vapor held in saturated air (100% RH at a given temperature) and the pressure exerted by the water vapor that is actually held in the air being measured at the same given temperature.
And easy way to understand vapor pressure deficit.
The VPD is currently regarded of how plants really 'feel' and react to the humidity in the growing environment. From a plant's perspective the VPD is the difference between the vapor pressure inside the leaf compared to the vapor pressure of the air. If we look at it with an RH hat on; the water in the leaf and the water and air mixture leaving the stomata is (more often than not) completely saturated -100% RH. If the air outside the leaf is less than 100% RH there is potential for water vapor to enter the air because gasses and liquids like to move from areas of high concentration (in this example the leaf) into areas of lower concentration (the air). So, in terms of growing plants, the VPD can be thought of as the shortage of vapor pressure in the air compared to within the leaf itself.
Another way of thinking about VPD is the atmospheric demand for water or the 'drying power' of the air. VPD is usually measured in pressure units, most commonly millibars or kilopascals, and is essentially a combination of temperature and relative humidity in a single value. VPD values run in the opposite way to RH vales, so when RH is high VPD is low. The higher the VPD value, the greater the potential the air has for sucking moisture out of the plant. As mentioned above, VPD provides a more accurate picture of how plants feel their environment in relation to temperature and humidity which gives us growers a better platform for environmental control. The only problem with VPD is it's difficult to determine accurately because you need to know the leaf temperature.
This is quite a complex issue as leaf temperature can vary from leaf to leaf depending on many factors such as if a leaf is in direct light, partial shade or full shade. The most practical approach that most environmental control companies use to assess VPD is to take measurements of air temperature within the crop canopy. For humidity control purposes it's not necessary to measure the actual leaf VPD to within strict guidelines, what we want is to gain insight into is how the current temperature and humidity surrounding the crop is affecting the plants. A well-positioned sensor measuring the air temperature and humidity close to, or just below, the crop canopy is adequate for providing a good indication of actual leaf conditions.
Managing the humidity in your indoor garden is essential to keep plants happy and transpiring at a healthy rate. Transpiration is very important for healthy plant growth because the evaporation of water vapor from the leaf into the air actively cools the leaf tissue. The temperature of a healthy transpiring leaf can be up to 2-6°C lower than a non-transpiring leaf, this may seem like a big temperature difference but to put it into perspective around 90% of a healthy plant's water uptake is transpired while only around 10% is used for growth. This shows just how important it is to try and control your plants environment to encourage healthy transpiration and therefore healthy growth. So what should you aim to keep your humidity at? Many growers say a RH of 70% is good for vegetative growth and 50% is good for generative (fruiting /flowering) growth. This advice can be followed with some degree of success but it's not the whole story as it fails to take into account the air temperature.
If your growing environment runs on the warm side during summer, like many indoor growers, a RH of 75% should be maintained for temperatures between 79-84°F (26-29°C.)
The problem with running a high relative humidity when growing indoors it that fungal diseases can become an issue and carbon filters become less effective. It is commonly stated that above 60% RH the absorption efficiency drops and above 85% most carbon filters will stop working altogether. For this reason it is good practice to run your RH between 60-70% with the upper temperature limit depending on your crop's ideal VPD range, in the example it would be 64-79°F (18-26°C.)
The table also shows that if your temperature is above 72°F (22°C), 50% RH becomes critically low and should generally be avoided to minimize plant stress. Please understand that by presenting this information we do not want you to go to your indoor gardens and run your growing environment to within strict VPD values. What's important to take from this is that VPD can help you provide a better indication of how much moisture the air wants to pull from your plants than RH can. If you want to work out for yourself the VPD of your plants leaves you can follow the steps below:
See how the vapor pressure deficit changes when there is a smaller gap between air temperature and leaf temperature.