Thanks, we try to be as transparent as possible with everything. There is a virtual tour, just like real estate, on our website under “our facility”.
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On the topic of reheat I think there is some nuance to be worked out.
I don’t think it’s quite the panacea that the cannabis.mechanical guy is making it out to be (his hubris is off the charts), especially if you are generating the heat using electric heating coils or propane/natural gas and not some form of hot gas reheat. Hot gas reheat means using heat already produced somewhere in the process as the source of the reheating energy.
Some packaged A/C units (as opposed to split systems) are equipped with hot gas reheat because they have all the refrigeration components located relatively close together and they can split the hot gas stream from the compressor outlet and route some of it to a coil in the outlet duct and use that as the reheat source. This is much more efficient than using an outside heat source. Standalone dehums are the same way and are the most efficient at heat recovery because they are specifically designed for dehumidification only and don’t have to worry about also functioning as an A/C. Split A/C systems are not generally equipped with hot gas reheat because the condenser is usually mounted far away from the evaporator and it would be a pain to route some of the hot gas from the compressor back to the evaporator.
Yes the standalone dehums are a large upfront cost.
But I think if you are using a heating source that comes from a completely external source (like electric heat strips or gas) the additional cost to your energy bill will be much larger than what you would find from a heat source that uses some form of partially recovered heat (like a standalone dehum or hot gas reheat in a packaged A/C system) that there will be a point where your higher energy bill will eclipse the total cost of the dehums and you will start to “lose” money versus the lump sum cost of the dehums.
This is true even though lots of people think, “Well standalone dehums output a lot of heat that my A/C system then just has to cool back down, doesn’t that cost add up?” Well yes, but since the extra heat that the dehums put out is sourced/recovered in a very efficient way (from the compressor output of the dehums refrigeration system) it’s actually the most efficient way to go about the process. Standalone dehums are like free reheat.
Try thinking about it another way: When you add electric reheat strips to your A/C think about how your condenser up on the roof is still giving up all that heat from the compressor into the atmosphere and then you are paying to regenerate that same heat with your electric heating strips. Do you see how this is highly inefficient and it would be much better to just use all that heat your just belching into the atmosphere? That’s exactly what a standalone dehum does (see the diagram in my post up higher in this thread).
Some of these external electric heating coils I see being added as reheat sources are 15kw+. That is going to add up quick on the power bill. External propane/natural gas probably isn’t as bad but still not very efficient because it’s completely “new” heat, not recovered from anywhere in the system.
In other words, I think this boils down to more of a capex vs opex dilemma. Can you outlay a large capital amount upfront to save money in the long run or are you hurting for funds and need to sacrifice long term savings in order to save a little bit of money today? I think ideally you outlay today and save in the long run which means standalone dehums and smaller A/C’s.
There is also the point that if you are using A/C’s with reheat as your only dehum source you will probably need to upsize your equipment versus using A/C plus dehums and that will add to the total cost.
There is also the point that the A/C system cannot simultaneously cool and dehumidify when equipped with reheat. It’s one or the other. This could be an issue for some people.
There is also the point that certain building codes limit the amount of reheat allowed in certain spaces. This could be a giant issue for larger legal operations.
What do you think?
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I think you hit on most relevant topics regarding reheat and dehumidification. Hopefully everyone knows using waste heat for reheat is more efficient than converting an energy source into heat for reheat. Granted that efficiency has cons to go along with the pros…
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This is what really has me confused. I don’t think most people realize this.
They don’t understand that converting waste heat into reheat is specifically what a standalone dehum does. And it does it at a very high rate of efficiency, I think close to 100% on the best units.
All most people seem to see is the (false) idea being propagated by this Landry guy that they no longer need to buy dehums or that dehums are “useless” and inefficient and all you need is the A/C’s you were going to buy anyways.
Most people trying to push this tech on IG seem to be wowed by the simple fact that the possibility of using reheat in an A/C (old technology) exists in the first place while ignoring anything about the overall efficiency compared to dehums.
All I have ever seen cannabis.mechanical talk about is adding reheat to existing systems using electric or gas (outside sourced), never hot gas reheat or other recovered sources.
What really got me thinking about this topic was seeing cannabis.mechanical going off at the mouth on a JungleBoys post talking a bunch of shit because they’re putting in dehums at their Ocala build.
I mean, if you have a small grow with a mini split this type of thing might make more sense (but not really). But on a huge warehouse grow like the JungleBoys Ocala facility? What a joke to even suggest using electric reheat over dehums. And I say that not just for long term opex reasons, which are major, but also like I mentioned above: building codes. I’m sure it varies by jurisdiction, but of course with anything these days there are energy efficiency guidelines and codes to follow (ASHRAE 90.1). I would hate to have all that electric reheat installed and then be shut down for a code violation.
Mr. Landry really talks himself up a lot, I believe he has dubbed himself the “godfather” of bringing reheat to cannabis. I’ve even seen him refer to reheat as “Landry Mode”. You can always tell these guys when they start giving themselves the nicknames. So much hubris.
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I quit following that guy years ago because of aforementioned reasons. Granted I have implemented many non waste energy reheat systems on split and minisplit cooled areas. The customers just could not grasp the physics I was throwing down and secondly they did not have the $$$ to afford the dehum they needed. Many of these systems are still running, inefficiently lol, but not producing PM covered plants anymore…
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Ha, the cannabis.mechanical guy made a post with a “dehums for dummies” book cover yesterday and I left a comment outlining how electric reheat kits jack up the power bill and standalone dehums are actually highly efficient reheat machines and he deleted it with no response.
If that doesn’t tell you everything you need to know about the guy I don’t know what will.
The guy’s a Grifter with a capital G.
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This can maybe fly in veg but even in veg you want to stay consistently below 60 rh to stay away from powdery moldew popping up (at least in michigan). 65-75 rh in flower your almost guaranteed to have powdery moldew and bud rot
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