It may be interesting to look at in some forms, but mold is the bane of a building manager’s or cultivator’s existence. It makes spaces designed for people uninhabitable and when it shows up in an indoor agriculture facility it can mean that an entire crop must be destroyed. Unfortunately, mold mitigation is difficult and expensive.
For the last 20 years there has been a great deal of research into mold by professional engineering associations. Founded in 1894 the American Society of Heating Refrigeration and Air Conditioning Engineers (ASHRAE) has well over 50,000 members. The gold standard in the climate control business are peer-reviewed publications from ASHRAE. I accept ASHRAE’s conclusions on any subject as gospel and I believe you will come to the same conclusion.
When it comes to mold, the results have been in for some time. It turns out there is no magic bullet. Like a chronic disease; you can control it, but you cannot cure it. Here is what the experts tell us about some of the ways people are trying to control mold.
Why does mold grow?
The results are definitive, and the action taken to prevent mold is clear.
Mold needs four things to exist and these four things are arranged in what they refer to the mold square. Break one side of the square and you can control mold. Let’s look more closely at each side of the square.
1) Food Source: mold eats anything organic. Mold has been know to grow on glass. Not because it eats glass but because the glass was dirty and the mold found something in the dirt it could eat. Keep your rooms clean but otherwise forget about starving out the mold. Ain’t gonna happen.
2) Mold Spores: Mold spores are everywhere. Most of them come in from outdoors but they stick to our shoes and clothing and anything else brought in from outdoors. The way to minimize mold spores is to minimize these sources. Outdoor air is the worst. There are other steps you could take but the most effective is to minimize or eliminate outdoor air. If you must bring in outdoor air it must be filtered through a filter with a minimum efficiency of MERV-8. The filters need to fit tightly in the filter housing so that air, and mold spores can’t sneak around the edges of the filters or the housing.
3) Temperature: The temperature you need is the temperature you need. Not much you can do about that but if a little change of the temperature will reduce mold and not impact the crop you may want to consider it.
4) Moisture: Moisture comes in two forms 1) open water like puddles and 2) humidity in the air. Humidity is what you should be most concerned with. Different strains of mold thrive at different humidity levels. A good guideline: keep the relative humidity below 60% at all times. Many varieties of mold thrive at 60% RH and above. That 60% is the RH at the plants’ leafs and flowers.Your humidity sensor may likely be across the room or in a dehumidifier. It is vital that air be circulated through and around the leaves and flowers at all times to make sure the local humidity there is no higher than the humidity seen at the sensors. To be safe I would bump the humidity setting at the sensor down to 55% to give yourself a little safety factor at the flower.
Do Ultra Violet Lights Help?
ASHRAE has a whole chapter devoted to Ultra Violet (UV) lights in its Humidity Control Design Guide on HVAC systems and equipment. In general, when properly applied, ultra violet lights have different levels of effectiveness at inactivating bacteria and fungal spores.
• UV lights are most effective against bacteria like the ones that cause staph infections, and do a decent job on bacteria like the ones that cause tuberculosis.
• They have some effect on bacteria like the one that causes anthrax.
• At the very bottom of the list; UV lights are good at inactivating fungal spores (mold).
The published data indicates: the less effective UV lights are against something, the more concentrated the light needs to be, and the longer the organism must be exposed to it. Unfortunately, there is a significant lack of data that explains how much exposure you need to kill a mold spore. I found well researched papers on the effectiveness against bacteria, but nothing on mold. As near as I can tell, ASHRAE is silent on that topic.
UV lights consume power and generate heat. Just like all the other lights in the building, they add to the cost of running your air conditioning. Here are some quick calculations that will get you into the ballpark of what that really costs you. If your building needs 100 tons of air conditioning, adding UV lights means you must buy an additional 2 tons to cool the added heat load from the lights. If you have 100 tons of air conditioning with UV lights and you pay $0.10 per kW of electricity, your rough cost to operate the air conditioning 24/7/365 is about $110,000. Add the cost to operate the UV lights and the additional air conditioning to cool them and that cost goes up about $10,000 more.
Finally, light bulbs burn out. If UV lights are installed inside ducts or air conditioning units you need a method to tell you when the bulbs burn out. You can’t just open the unit and look at them because safety regulations require a switch that turns the lights off when the unit is opened. ASHRAE recommends that a window be added so people can look at the lights in operation, but the window rarely gets installed in the real world. As a result, a lot of UV light bulbs don’t get changed when they burn out.
Conclusion: UV lights are good for controlling bacteria. Mold? Not proven.
Control Mold with Environmental Control Equipment
One of the first environmental control go-to’s is a dehumidifier. The mechanics of a dehumidifier is pretty straight forward and they all work pretty well. But, keep in mind that understanding the relationship between a dehumidifier’s controls and a sensor is very important. The humidity control from a dehumidifier is only as good as the sensor used to detect it.
When dehumidifiers are mass-produced for the retail market, the first place manufacturers scrimp is in on the sensor. You can buy sensors for $5. Yes, they are slow and inaccurate, and they are designed for use in a factory, not a laboratory. If the dehumidifier is rated in pints per day, my professional experience tells me that it has a sensor that is no more 5% plus or minus accurate. That means that if you look at the display on the dehumidifier and it says it is 55% — the actual humidity measured by the highest quality sensor may really be 60% RH or it might be 50%. You just don’t know.
When it comes to sensors — you get what you pay for. If you want an accurate sensor that reacts quickly to changes in RH, the more expensive it will be. But again, you get what you pay for. More expensive humidity sensors provide more accuracy — within 1% of the actual number. That means: if you’re seeing the display at 50% — the real humidity measured by the highest quality sensor may be between 49% to 51%. That small difference is most likely something you can live with.
Learning to control the environment in which mold can live is your best chance at keeping mold from taking over your facility. So investigating proven systems designed to control mold through the temperature and humidity in data centers or an indoor agriculture will help you prevent unwanted moisture from condensing on surfaces within your facility.
The Data Aire Service Team regularly works with and supports HVAC service technicians all over the world as they call in to discuss any of the large array of issues that they may face in the field.
It’s always great to speak with another HVAC technician because we have our own language and can relate to each other’s experiences. We understand the challenges within the field. It doesn’t matter if we are communicating for the first time; it feels like we have known each other for years.
How Does Our Service Team Resolve Your Issues?
Tech Support’s primary focus is not just to find the failure, but to find the reason of failure. We have a set of questions prepared for every technician’s call. The successful calls are from the well prepared and organized technicians who have all their information gathered and ready, like policemen looking at every piece of evidence and only believing facts. Having these facts helps us to resolve their issues very quickly.
Below is the list of questions that service departments use to gather the facts:
1. Date the problem occurred
2. Customer information that may be useful
3. Ambient or room conditions of the unit
4. Unit information. Most importantly, the serial number, but we’ll take any other info too!
5. Reported problem. Be specific. Some customers have a lot of actual useful information that may help us get to the root cause
6. Any relevant history? Unit run time? Maintenance history? When did the problem start? Number of times this problem has occurred.
7. Present alarms and alarm history
8. Is the unit installed per Data Aire IOM?
9. What have you found? Detailed explanation on how the component was condemned. What test or instruments were used, measurement results, how it was done and for how long.
10. Failed component/part information? (Model #, Serial #, Part #)
11. If changes were made, what were the reasons for the changes?
12. What are your suggestions and the reasons for your recommendations?
13. Do you have a follow up date?
14. What are the actions that need to be taken and who is taking responsibility?
15. Reason of failure and how it was determined
Identifying the reason of failure is the most important information we need. The last thing you want to do is go out in the field and look for a part or seek support and not have all the information required. You want to prevent the failure from reoccurring. We have seen technicians replace a part and have it fail a few days later.
How Should HVAC Technicians Prepare Before They Call Support?
One thing we often notice is that these seasoned professionals have developed a specific skill for troubleshooting during their career. That skill is using all their senses. The best technicians use their eyes, ears, smell and touch to find answers. They must be good listeners and gather as much information/details as possible before grabbing any tools from their tool box. They listen to the customer for their input or they listen to the unit for any abnormal noises that can point them to the direction of the problem. Second, they visually inspect the unit for clues, such as stains, wear and tear, or burnt marks. Third, they feel for infiltration and temperature changes. Lastly, they use their sense of smell to detect suspicious odor, such as mold or a burnt-out compressor.
These service technicians have attended our service training and stay up to date with changes we make to our products. They know and understand the sequence of operation of the unit in question. They know the purpose and functionality of the components and what activates the safety switches. For example, they know if the safety switches are activated by pressure, by voltage, by resistance, or by temperature. They are also effective communicators. They report and train everyone involved. They don’t leave anyone in the dark.
Data Aire Service Department has created a Troubleshooting Guide to help those new to the trade.
Maintaining the consistent performance of your HVAC equipment is vitally important for mission critical environments. Our service techs understand the challenges and issues technicians face in the field from communicating with them on a regular basis. The Data Aire Service Team is here to support HVAC service technicians and to help resolve any issues they encounter in the field.
Servant Leadership in the Built Environment
“A new moral principle is emerging which holds that the only authority deserving one’s allegiance is that which is freely and knowingly granted by the leader in response to, and in proportion to, the clearly evident servant stature of the leader. Those who choose to follow this principle will not casually accept the authority of existing institutions. Rather, they will freely respond only to those individuals who are chosen as leaders because they are proven and trusted as servants. To the extent that this principle prevails in the future, the only truly viable institutions will be those that are predominantly servant-led.”
Robert Greenleaf shared this assertion in his 1970 essay, The Servant As Leader. While Greenleaf was not referring to industry, I, as a practitioner of Greenleaf’s principle, nonetheless, see Integrated Project Delivery (IPD) as the manifestation of Servant Leadership in the institution of the built environment. The design community, builders, manufacturers, and operators are the ones responsible for conceiving, creating, and shepherding the built environment…to serve it.
A project delivery method, at its core, is comprised of two categories of individuals or companies – those who decide, design and determine, and those that supply, construct and install, and operate. Founded on a culture of trust, and in service of the owner and the program, IPD integrates those two into one. As the Construction Specifiers Institute states, “when properly executed IPD affords
- Owner, design, contractor, and supplier teams to interact before the construction docs are completed to make decisions and commitments about the design that have cost implications.
- Decisions to be made and orders placed for materials, products, and equipment that require long lead times
- Buyout phase to be better managed because of the team interactions and extended time for making effective decisions”
Breaking Down Project Management Silos
The last several years all manners of industry have been talking of ‘breaking down silos’. Much of this is surrounding corporate structures coming from a fundamental need for effective collaboration that applies anywhere there are two or more individuals or groups interacting. Whether in classrooms, the board room, or the construction site people are choosing to work together in less traditional, structured ways to gain effectiveness and efficiency.
To execute on IPD, many builders are taking cues from lean manufacturing and reapplying as lean construction. In lean manufacturing, sometimes referred to as “the Toyota Way”, no one tool or tactic — gemba walks, TAKT time, 5S, 8 wastes or other — will completely lean out the process, but composed as a system have proven highly effective as I’ve seen first-hand. Jonathan Cohen, FAIA, writes “Just as BIM is a tool that is useful, but not in itself sufficient for implementing IPD, lean construction is a set of tools in support of IPD but is not the entire process.” These two disciplines, lean manufacturing and lean construction, converge at pre-fabrication and modular construction to achieve mass customization – a collaborative solution, executed with speed, delivered at scale.
As a formalized delivery method, IPD involves contractual relationships that differ from traditional design-bid-build types of agreements. Shared goals and shared incentives help to align priorities to insure the team leaders are serving the owner with a unified front. An example of this would be access by the entire IPD team to the entire budget enabling compromises to shuffle across traditionally unrelated line items for the good of the project without concern for protectionism of a specific trade or item. “In IPD, value engineering is a continuous process, rather than an unwelcome surprise at the end of the design,” writes Cohen.
Choose Your Integrated Project Delivery Team Wisely
IPD team selection becomes less of a traditional bid award process and more like the employee hiring process where in addition to qualifying technical expertise we also focus heavily on exploring the intangibles to achieve the best possible cultural fit of individuals working with individuals and organizations teaming with organizations.
As the manifestation of servant leadership in the institution of the built environment, Integrated Project Delivery brings lean manufacturing and smart organizational culture practices to the design and build world.
The result is faster, smarter, better.
The inside of your gPod needs to be dry to ensure that you get the best crop and the longest life out of your equipment.
Water in the unit anywhere except inside the condensate drain pan underneath the cooling coil is cause for concern. Normally a wet unit means that water is somehow getting out of that pan.
The water may start to rust some of the internal parts of your gPod. Even worse, water inside the gPod creates a favorable environment for mold growth. If enough water leaves the drain pan it may eventually run out of the unit and onto the floor.
Possible Causes of Leaks and How to Fix Them
If you detect water inside the cabinet of your gPods, take immediate action.
First, check that the unit is mounted evenly in all directions. Adjust the unit as necessary to make it perfectly level both from front to back and from left to right. The water is supposed to be collected by the pan and which then immediately runs out the drain hole at one end of the pan. If the unit isn’t level the water will build up in one corner and spill out of the pan into the unit.
Next, make sure that your condensate drain pipe diameter is the correct size. In no case should the drain line from any single unit be smaller than ¾” diameter. That size is determined by the plumbing code so your inspector should catch this. When the ¾” condensate drain lines from multiple gPods are tied together into a single common drain line, the pipe diameter of the common line needs to be larger than ¾”. Where the second gPod is tied in, the common drain line will be handling twice as much water, so it needs to be bigger. Here is the chart that is usually used to size those pipes. Please note that your local codes may differ, and you should always follow your local code.
Get Trapped the Right Way with a P-trap
Every gPod needs a P-trap on the outlet of the coil drain pan. The supply fan in the unit pulls a negative pressure on the condensate drain line. Without a trap, the fan will suck air backwards through the drain line and up through the drain pan outlet where the water is supposed to drain out of the pan. This continuous flow of air coming up through the drain hole prevents the water from entering the drain line and leaving the pan.
When the fan runs it pulls the water in the trap up the drain pipe, like sucking on a straw pulls liquid up the straw. The fan is only strong enough to suck the water a few inches up the drain line. The P-trap is designed to make sure that when the fan is sucking as hard as it can, there is still enough water in the U-shaped bottom of the trap to keep air from getting past the column of water. When the fan is pulling as hard as it can, if there is still water in the bottom of the trap, air can’t get past and the water will drain out of the pan.
Getting the P-trap Dimensions Right
Once you know the drain is the correct pipe size, check the dimensions of the P-trap on the condensate drain.
The dimensions required for the trap to hold enough water are calculated based on the installation and the strength of the fan in the unit. Dimensions have been added to the drawings below to give you an idea of what your traps should look like. The drawing on the left is for units with bottom drain connections. The drawing on the right is for units with side drain connections.
The dimensions shown below will allow your gPods to drain on virtually any project. Shorter dimensions may work, but a trap with dimensions less than 4 inches is probably asking for trouble.
The small dimension is equally as important as the big dimension. The small dimension must be no less than the big dimension minus one inch, divided by 2. Contact your gPod representative and he can consult with the gPod engineering department to determine the precise dimensions your traps need.
Other Unlikely, but Possible, Causes of Water Getting Out of the Drain Pan
There could be a leak in one of the corners of the drain pan. The pan’s corners are welded and then sealed with silicone. But, on rare occasions, a drain pan may develop a leak. The fix is to remove all the old silicone sealer, dry the pan thoroughly, and apply new sealer to the leaking corner.
Finally, and least likely, the fan may be turning so fast that it sucks the condensate right off the cooling coil before it has a chance to run down the coil fins and into the pan. gPods are specifically designed to prevent this so try everything else first. If that doesn’t solve the problem, please call the Data Aire Service Department or your local gPod representative for help.
This is the first in a series of blogs about air conditioning myths indoor growers believe.
Myth #1: Just a Shot of Freon is All It Takes
The first myth I’d like to debunk because I dislike it the most is the “it just needed a shot of refrigerant (Freon)” myth. A shot of Freon is almost never a permanent fix for your air conditioner’s problem.
There is one main reason to add refrigerant to an air conditioning system. The reason being that the amount of refrigerant in the system, commonly called the charge, needs to be adjusted. It is not unusual for refrigerant charge to need adjustment ONCE during the first year or 18 months of operation. Occasionally, the charge may need to be adjusted again, after several years of operation.
All modern air conditioning systems are hermetically sealed. Nothing goes in; nothing goes out. There are only two ways that Freon can leave the system. It can be taken out intentionally or it can leak out.
Your service technician’s primary objective is to get your air conditioning up and running in the shortest time possible. If you want him to do more than just that, you must ask him to do more.
Guidelines to Follow When Interfacing with Your Service Technician
1: Get an explanation before you pay a service technician for adding “a shot of Freon” to any air conditioning system. This applies to the air conditioner in your house and your car as well as the systems in your grow.
2: Be sure to get a copy of every service ticket and save them in a file. Make a note on the ticket about your discussion around a leak. You may need these in the future. (See Rule #3)
3: Never ever allow a shot of Freon to be added to the same system twice. Obviously, there is a leak under these circumstances. The leak needs to be fixed or you are just throwing good money after bad.
Questions You Need to Ask your Technician
1: “How much refrigerant did you add?” They know exactly, because they charge you by the pound.
A legitimate adjustment to the charge consists of adding a pound or so of refrigerant, at the most. If the technician added more refrigerant than that, you likely have a leak. Adding refrigerant without fixing the leak is like giving a blood transfusion to a patient without stopping the bleeding.
2: “Where was the leak?” closely followed by “Did you look for the leak?” Service technicians hate to find and repair leaks. It messes up their whole day. They start the morning with a list of places to go and equipment to fix. It will take all day to find and repair a refrigerant leak. If the technician didn’t find the leak, call the service company and make an appointment for the technician to come back when enough time has been built into his schedule to do the job.
Some customers would rather pay $500 for a service call once or twice a year, forever, to avoid paying a $1,500 onetime charge to fix the leak. Service companies will come back to add refrigerant to the same system again and again for as long as you want them to. It is quick and it is easy.
Repairing the leak will not be cheap but it is way better than the alternative. A leak is going to lead to a major failure at some point. The small leak will get bigger and bigger. A big leak can destroy the compressor. Replacing the compressor will cost several thousand dollars and the unit will be out of service for a couple of days.
Remember… Find the leak. Fix the leak.
Look for the next myth in the series…
“It’s too complicated for you to understand.” No one ever wants to hear that, and it’s definitely not true.
You Make Our Day
Every cannabis industry convention I have been to in the last year has surprised me in terms of scale and scope but even more so in terms of excitement and CannaCon Seattle was no exception. I always arrive to our booth early so I can walk the show floor about an hour before the official start; all the exhibitors are putting the final touches on the booths, the walkways are quiet and calm yet the focus and anticipation is palpable. After finishing my ‘morning stroll’ I headed back to our booth to catch up with our local team and prepare for day. Once the gates were open it was clear that Seattle, and for that matter, the Northwest region was ready for action.
One of my favorite things about the cannabis industry is the collaborative culture. Instead of giving out the same 60 second set of talking points, we get the opportunity to learn about the business of others and dig in to determine if a partnership makes sense. The tangible outcome of this is that we get the opportunity to zoom out and learn about parts of the business we don’t directly touch but significantly impact.
Environmental Control Collaboration
An example of this is when I had a great discussion with an integrator. Day-in and day-out, he installs controls for lighting, irrigation, and various other systems; through our conversation we uncovered that we have both been asked about expansion of our control platforms. gPod controls temperature, humidity, and CO2 but we have been asked to control lighting and irrigation – the control vendor controls irrigation, lighting, and scheduling but has been asked to control temperature, humidity, and CO2. The connection we made uncovered new ideas and strategies for how we can collaborate, learn, and provide efficiencies to the grower.
Choosing an Environmental Control System – The gPod Team Can Help
As the conference rolled on we moved closer and closer to my break out session talk on the “process of system selection for your indoor grow.” The cannabis industry has many unique features but one of my favorites is the passion the cannabis growers and investors have on every aspect of the operation. However, I have seen this passion lead to miscommunications in the construction process which can ultimately manifest themselves in slower time to harvest and lower yields. This is why the project delivery process is so important and it is our goal at gPod to help guide the ownership team from back of napkin idea to construction to phase two. The two takeaways I hoped for all the attendees to walk away with were ‘there is value in the process’ and ‘work with an experienced team.’
CannaCon Seattle was one of my favorite cannabis industry trade shows; I learned a lot, collaborated a lot, and had a chance to start a lot of new relationships. gPod is a member of the cannabis community and a collaborative team player; the next show you are at stop by, say hi, and let us learn about your business.
In the meantime, if you’re interested, check out our new animated gPod video.