I’m having issues finding the proper hvac and dehumidification combo for my grow. what are you guys using? I’ve looked into stulz, cultiva, gpod, agronomics iq, desert aire, etc. the costs of those are all outrageous. I’ve got 3 small rooms with 12 1000w de hps lights. 16 plants per light. 3 5x20’ benches per room. These guys are talking $30-50k per room lol. I’m thinking going old school and using splits or standard hvac units with an Anden or quest…
Happy chatting and growing!
For that size you should use standard package units.
Are the standard 3000 btu per 1000w hps standing true or is there a better way to Guage the tonnage of hvac required?
Have you had a manual J load calculation done yet?
A load calc?
Vinny you are right, load calculation. Then you look at the objective, it is control during the operating periods and during transitions. Our little history indicates poor control in rooms using standard refrigeration/commercial units, mini splits and dehumidifiers. Technology has a a cost, so does cutting corners. A huge percentage of the problems in the industry are directly related to the operator approach. It is vastly more important to consider both capital cost and cost of ownership and establish the real cost of ownership. Every minute the room is out of control no matter how short is the opening for an undesirable organism to get it start. A room with anything other than flat line control is out of control as much as it is in control. A room that is anything other than a controlled optimum is a liability. Any inference that equipment costs are outrageous needs context. In out business we analysis for our clients what success looks like, a small space my not be a good reference point for a commercial success. There is no free lunch.
The best option is to get a load calculation done. Another option is to estimate the best you can then add bit of a buffer. A unit with stages or variable speed compressor would increase the efficiency. To give yourself a ball park add up all the wattage in the area to be cooled. Take your total wattage and multiply by 3.414. This is the BTU per watt. With this number it will get you an idea of what is needed for your equipment. Now take the square footage you should be ok to use the estimate of 20btu per sqft then add the heat load from your previous calculations. Hope this helps. If not look up the documentation for how to do a manual heay load calculation.
What units do you suggest ?
Who offers flat line operation?
We are having success with AAON packaged RTU’s with Energy recovery wheels (to get benefit of an economizer without outside air intrusion), dual variable compressors with hot gas reheat, natural gas heat, and the most important part, the controls. This handles cooling and dehumidification but is not cheap. This type of system is around $5k/ton (installed with ductwork) on a larger scale than you are talking about but I’m sure there are similar solutions on a smaller scale. Our units are 20.5 tons each. Controls screen shot attached for visual reference.
Finding systems with integrated dehumidification at an affordable price at that scale can be really challenging. Integrated dehumidification systems (either hot gas reheat systems like what you’ve been looking at or 4 pipe heat recovery chilled water systems) are generally more cost effective (and have a much shorter pay back) at a larger scale. With that said, you can implement a modular or entry level chilled water system to get the redundancy and electrical infrastructure benefits at a fraction of that cost. High efficiency split units with the right dehumidifier aren’t a completely unreasonable option at this small scale either, depending on your location and the operational challenges associated with weather conditions. Give us a call at 303-993-5271, or DM me your contact info and I’ll reach out–we’d be happy to talk you through your options, rough budgets, and the pros/cons of the various approaches to help you decide what’s best for you.
You might want to reach out to brandy keen at surna as they are experts at complex systems. IF you have existing HVAC systems and want to look at increasing cooling efficiency, reducing energy usage with a simple, one-time fluid treatment, our CryoGenX4 technology may be an option.