Humidor Dehydration: Why is it necessary in a sealed humidor?

[PigFish]

There has been considerable talk in the Humidor forum as of late regarding the “dehydration process.” In a recent topic about a walk-in humidor project it was mentioned as a recommendation by a tobacconist that a new walk-in be built without sealing it, assuming that the exterior ambient would provide sufficient diffusion of water so that no dehydration process would be necessary. It was at least implied, as I read it, that without leakage and transfer of water to the outside environment, the humidor would over hydrate. That ‘leaving the door open’ or leakage to the outside macroclimate would solve the problem.

I find it interesting that dehydration is rarely a topic of humidor study unless I bring it up! In talking to a lot of smokers looking to solve humidor problems, I find it one of the main reasons a cigar enthusiast contacts me. It does appear, at least to me, that this important topic is all but ignored by the mainstream community and humidor builder alike. It would appear also, that many of the folks that I speak with have some sort of issue with high rH. It also appears, that most folks live with it rather than deal with it…

While I am not going to bore you with an in-depth discussion of how I solve the problem, I do find it an interesting topic. After studying hundreds of charts of humidor performance, I thought I would parse down yet another chart of one of my humidors to show how I deal with the issue.

Of course you need the proper appliances and controls to meet the foe of over-hydration in order to beat it down! I use refrigeration to perform the task, as there is little that strips water from space like a cold plate that is at or below the dew point.

Chart A shows an overall view of the process. The chart shows one of my humidors at work in my lab at about 3am. For the record the outside conditions are such that the heater is running in the humidor to keep the temperature up. This has little actual effect on the process itself, but it does act to keep the temperature in the range that I wish to store. Repeated dehydration cycles when the ambient is below the storage set point would eventually decrease the heat and temperature in the humidor over time. This is off topic!

Chart B be gives you an idea about how a sealed humidor will act at a low temperature and the duration of the natural cycle of a sealed humidor to over saturate itself with water if left to its own devices. As you can see, it takes 9 to 10 minutes to move from a low-end rH condition to a high-end rH condition in this particular ambient set of conditions.

Chart C shows some of the dehydration process and the duration of the dehydration cycle. The dehydration cycle itself runs about a minute and a half. It should be noted that most processes in humidors overshoot their run times. Knowing how to deal with this is learned empirically and learning how to produce desired results is borne out of experience. There is no handbook for it! Only testing and experimentation will yield these kinds of results. Knowing when, how and how long to run appliances is as much art as science.

The two square-wave signals are generated by my appliances to track their performance. What you see here is the time line of these appliances actually switching on and off. Without such data I would simply be guessing at where and what to adjust. I thought it would be interesting to show how precision instrumentation performs to keep my humidor ‘in line’ so I included the signals on the chart. This is ‘inside baseball stuff,’ but I thought it might be informative.

If I analyze the chart with my software the actual range for the rH throughout the cycle is only about 1.5rH. A cooling cycle itself will take a greater toll as it is easier to remove water than to cool air but that is another story.

In my opinion a sealed humidor with an active (wet) humidifier requires a dehydration cycle to remain within [my] limits. If you were at all interesting in how I came to that conclusion… well… this is how!

Thanks for reading!

-the Pig

[Skyfall]

Once again Ray -

[CUBANO]

I always love reading your posts. Thanks!

[canadianbeaver]

Ray you write the Penthouse forum of FOH.

[PigFish]

Ray you write the Penthouse forum of FOH.

… -LOL

I figure with enough influence I can get Rob to rename the Humidor Tutorial Forum, 'The Pig's Pen.' -LOL

[PapaDisco]

So . . . is having a deliberately leaking humidor a good strategy or a bad strategy? Adding active dehumidification adds complexity, but the 'complexity' of refrigeration is pretty reliable anymore and therefor not a bid deal. If you're outside humidity never exceeds your target humidor humidity, then I suppose this passive strategy (deliberately leaky) is a good alternative?

Where I live it wouldn't work, because there are week long stretches during the year that go over 75% humidity.

With the next house project here, I'd like to add a wine cellar, but set it up for cigar storage as well. Right now the cellar where this would go has a stretch of exposed bedrock. Very cool to look at, but would keep the space at an rH of 80% or worse when it rains. Wine could survive that but not cigars. The space as it is now, likes to sit at 45-55F and 75-80%rH most of the year, but then in the summer months can get up to 60-70F, so I guess I'll need AC, heat, humidification and dehumidification. Sheesh! Not exactly KISS!

[PigFish]

So . . . is having a deliberately leaking humidor a good strategy or a bad strategy? Adding active dehumidification adds complexity, but the 'complexity' of refrigeration is pretty reliable anymore and therefor not a bid deal. If you're outside humidity never exceeds your target humidor humidity, then I suppose this passive strategy (deliberately leaky) is a good alternative?

Where I live it wouldn't work, because there are week long stretches during the year that go over 75% humidity.

With the next house project here, I'd like to add a wine cellar, but set it up for cigar storage as well. Right now the cellar where this would go has a stretch of exposed bedrock. Very cool to look at, but would keep the space at an rH of 80% or worse when it rains. Wine could survive that but not cigars. The space as it is now, likes to sit at 45-55F and 75-80%rH most of the year, but then in the summer months can get up to 60-70F, so I guess I'll need AC, heat, humidification and dehumidification. Sheesh! Not exactly KISS!

This is a personal question… -LOL

It is a bad strategy for me, because I can do something about it. It is a marginal, but acceptable strategy for most people, because it works sometimes depending on conditions, or at least it appears to work for them until it does not work, at which time they deal with it until the conditions change again and they again believe that it works once more!!!

While this sounds silly I will assure you that most people store their cigars based more on hope and belief than science.

You have several choices regarding environmental control when storing cigars. You can choose to control it or you can let someone (mother nature) do it for you. Furthermore you can control the internal areas of your humidor (the microclimate) or control the external areas around your humidor (the macroclimate, or ambient conditions). Those choices are up to you!! The combinations of what to control and how to control them are numerous. Most will decide on a strategy that is, at least to them, logical, doable, and cost affective.

About how to do it, well, that is a different story! The beauty of the internet is that many will lend a helping hand and give you advice. The downside is that the advice is often wrong!

If you live in the arctic, you don’t need a freezer! The ambient then defines the requirements for your humidor just like your food storage. Beyond the ambient there exists the world of controlled microclimates. Just because a microclimate is ‘controlled’ does not mean that it will work. The appliances themselves cause problems. The means that one uses to solve a problem may not solve it at all. Furthermore one may create other problems as he attempts to solve one or more problems that he perceives exist currently. I have done this all before, I know a lot about it! This is where advanced design, controls and experience come into play. Just because you can afford to drive a 200mph car does not mean that you have the ability to control a car driving at 200mph! Just because you think you can do something does not mean that you will do, or have done a good job of it!

Most folks deal with an environment where they are not critical of temperature. This is mistake number one. Most folks believe that temperature has no relevance to cigar storage. Don’t believe me? There are all sorts of blogs saying rH is all that matters… While these folks are just wrong they continue to espouse the same opinions. There is not much in the way of fact checking when it comes to cigar theories on the net.

Lesson one. If you don’t build your humidor on a firm foundation of reality, it won’t likely work correctly.

Simplicity and cost factors drive most storage decisions just like any other decision. Take transportation decisions, for example. How you get to work is a personal choice. A limo or a bus will both get you there. Well, the bus might not always get you there on time. The reality of it being a reliable solution would be between you an your boss. You may define the same situation differently.

You all must define storage for yourselves as you would define the other choices you make in life. You must set the height of the bar were you believe it will benefit you and not be a detriment to your cigar hoard. We all place the bar at different levels. I admittedly set the bar rather high. I am fanatical about it, as you can see.

I am willing to take the heat for saying that I think that many people make poor storage decisions. I am also willing to be criticized as a storage fanatic, not grounded in reality. Others often consider those who are interested in accuracy and/or precision fanatics and I fit that description. I understand that stigma. To control, or to be controlled are therefore two sides of the same sword. Pick a side, or somewhere in the middle. You choice is up to you and relevant only to you.

I say if you can get it to work for you and it saves you a pile of ‘bread,’ money that you can use to buy more cigars, then why overcomplicate your life? On the other hand, why dodge a bullet when you can disarm the foe before it is fired? The linkage between real problems and imaginary problems will show up in your cigars sooner or later. Just because you can’t see it coming does not mean it is not coming, or that a problem does not exist. As a heart attach survivor… I can tell you this with a high degree of certainty!!!

If one is happy with the cigar that they pull from their storage then their job is done. Done at least for now. They are done until such time as their same system shows them their errors. Whether that day comes or never comes will be the deciding factor of how well you built your humidor…

People call me, sometimes with considerable despair in their tone with stories of what has happened to their cigars. I post this stuff to help others avoid such situations.

-Piggy

[superconductor71]

Active dehumidification IS a complexity, but mainly because there hasn't (at least to my knowledge) been made commercially available a product that will do it for us, as the Cigar Oasis or Hydra handle active humidification.

THAT is where the problem lies.

I'm all on board with everything Piggy says about control and accuracy and using science to store our cigars based upon fact. But I dont have a practical solution that has been offered. No, i'm simply NOT handy enough (at least that I know of) to wire logic controllers to a dehumidification device, nor would I know where to get one that will fit in my wineador alongside my cigar oasis.

Piggy you are, and this is what you do and that is why i'm sure your cigars are stored as close to perfect as anyone's.

I simply dont know of a practical way to GET that accuracy and control that you speak of, and I completely agree with.

I'd rather not risk my cigars to hopes, dreams and hocus pocus....but until a solution is offered that adds some kind of simplicity I feel stuck :/

~Drew

[PigFish]

Active dehumidification IS a complexity, but mainly because there hasn't (at least to my knowledge) been made commercially available a product that will do it for us, as the Cigar Oasis or Hydra handle active humidification.

THAT is where the problem lies.

I'm all on board with everything Piggy says about control and accuracy and using science to store our cigars based upon fact. But I dont have a practical solution that has been offered. No, i'm simply NOT handy enough (at least that I know of) to wire logic controllers to a dehumidification device, nor would I know where to get one that will fit in my wineador alongside my cigar oasis.

Piggy you are, and this is what you do and that is why i'm sure your cigars are stored as close to perfect as anyone's.

I simply dont know of a practical way to GET that accuracy and control that you speak of, and I completely agree with.

I'd rather not risk my cigars to hopes, dreams and hocus pocus....but until a solution is offered that adds some kind of simplicity I feel stuck :/

~Drew

What you are looking at mate, in the above posts of mine, is a simple 5.8 cuft wine cooler. I program/control the cooler to perform dehydration. It is a double duty appliance.

Thanks for the complements! Cheers- Piggy

[superconductor71]

What you are looking at mate, in the above posts of mine, is a simple 5.8 cuft wine cooler. I program/control the cooler to perform dehydration. It is a double duty appliance.

Thanks for the complements! Cheers- Piggy

Right, exactly! You can do that, but i'd dare say that most people could not program/control the cooler to perform everything. At least not without some decent instructions.

I didn't mean my post in any way to be derogatory towards you at all....I see all you have done, your knowledge far outweighs most of us (but definitely my own). I'm envious of how you can manage to make your wineador's function that way.

I think it becomes a "oh well, I will do what seems to be working for others" type of scenario because the thought of somehow making our wine fridges perform double duty, active hydration/dehydration through programming just seems daunting.

I'd certainly give it a go if I knew where to even begin and how to wire and program my cooler compressor to do that

[Skyfall]

… -LOL

I figure with enough influence I can get Rob to rename the Humidor Tutorial Forum, 'The Pig's Pen.' -LOL

YES!!!

[PigFish]

Right, exactly! You can do that, but i'd dare say that most people could not program/control the cooler to perform everything. At least not without some decent instructions.

I didn't mean my post in any way to be derogatory towards you at all....I see all you have done, your knowledge far outweighs most of us (but definitely my own). I'm envious of how you can manage to make your wineador's function that way.

I think it becomes a "oh well, I will do what seems to be working for others" type of scenario because the thought of somehow making our wine fridges perform double duty, active hydration/dehydration through programming just seems daunting.

I'd certainly give it a go if I knew where to even begin and how to wire and program my cooler compressor to do that

…Hmmm, definitely room for a gratuitous commercial plug here!!! -LOL I will resist it! ;-)

Mate there was noting said that offended me, not at all. I post this stuff for the sake of others and for those not really interested in the science of it, for the sake of intelligent discussion or at least entertainment.

I read your previous post and assumed that you were assuming that a specific "dehumidifier" was required for this process. I thought I would clarify that point, that no specific dehumidifier is required.

I wish I could say that wine cooler conversion was easy (at my level of expectation anyway). It really depends on what you expect out of it and are willing to put into it as a factor of time, money and some previously acquired skill with tools. I rate it somewhere between building Ikea furniture and building a radio controlled airplane. Going it alone takes time, money, tools, patience and an appetite for failure. I have an abundance of some of these things, bolstered by curiosity and the desire to build a better mouse trap. It all depends on what your goals are and your intestinal fortitude. I am an example of a guy who does not give up easily!

In any event I am glad that you have participated in the discussion! If you have specific questions that you don't feel comfortable posting, feel free to email me. My email is in my profile.

Cheers! -Ray

[Ginseng]

In my opinion a sealed humidor with an active (wet) humidifier requires a dehydration cycle to remain within [my] limits.

Your data leads me to concur with you.

For me, commercial humidity management systems are half-solutions, the whole lot of them. While the devices themselves can be programmed with any manner of control scheme, only actively managing humidity excursions below setpoint leaves the other half of the cycle poorly effected, as I interpret the point you're making.

Mental frame sets are conceptually limiting especially with respect to cigar humidity management. By this, I mean the model that the humidification/dehumidification must necessarily take place within the storage space itself. I would think that a vastly cleaner and more effective solution would be to take this "out of the cabinet."

For example, in an isolated partition in the lower portion of the cabinet would be situated a black box that delivers X% RH air to the storage compartments above. I envision an air recirculating system with water and a dessicant (molecular sieves, for a number of reasons) that routes and mixes the air between these two systems to deliver humidity at the output setpoint. So, assuming the air in the storage cabinet is reasonably well-mixed, the actual management of the relative humidity can be gentler than a bang-on, bang-off approach as the control inputs will be more subtle. Add in feedforward PID or fuzzy logic control and one could have a rather stable setup.

Wilkey

[PapaDisco]

Macro and micro is an important distinction. What I imagine is building something where the macro (the room) is actively managed to a safe range but if the systems fail, that macro will still settle within a safe range. Hence the cellar idea. Normally a big deep hole in the ground is stabile for temperature and humidity, but getting it to the right humidity, passively, is a trick. Then within that room, store the cigars in humidor with passive rH systems. The immediate environment around the cigars would be consistent and always slow to change because of the barriers of boxes and humi walls and because the macro environment would be managed to desired temp and rH, with a passive fail safe environment that wouldn't kill my sticks if the whole thing died when I was out of the country for a month.

[PigFish]

Your data leads me to concur with you.

For me, commercial humidity management systems are half-solutions, the whole lot of them. While the devices themselves can be programmed with any manner of control scheme, only actively managing humidity excursions below setpoint leaves the other half of the cycle poorly effected, as I interpret the point you're making.

Mental frame sets are conceptually limiting especially with respect to cigar humidity management. By this, I mean the model that the humidification/dehumidification must necessarily take place within the storage space itself. I would think that a vastly cleaner and more effective solution would be to take this "out of the cabinet."

For example, in an isolated partition in the lower portion of the cabinet would be situated a black box that delivers X% RH air to the storage compartments above. I envision an air recirculating system with water and a dessicant (molecular sieves, for a number of reasons) that routes and mixes the air between these two systems to deliver humidity at the output setpoint. So, assuming the air in the storage cabinet is reasonably well-mixed, the actual management of the relative humidity can be gentler than a bang-on, bang-off approach as the control inputs will be more subtle. Add in feedforward PID or fuzzy logic control and one could have a rather stable setup.

Wilkey

Ahhh… Professor Wilkey!

Welcome to the fray. You always bring the conversation to a higher level!

You are onto some rather advanced humidor design theory with your post and make some valid points. Isolation, for example, is an important concept in my designs. Isolation is a topic unto itself, and while I love to discuss it; practical concepts in appliance isolation by itself represents an entire tome of writing.

Before I delve too deeply here I would like to make some comments about conceptualization and reality from an expert perspective (mine). The conceptual view is a victor airway! That airway is ceiling unlimited and has 60 mile visibility! Reality, and the pragmatic practice of bringing an economical solution to fruition is of course a rocky goat path!!! The path is obscured, inhibited and overcast!!!

As an individual I am perpetually interested in the conceptual and the esoteric. New concepts and a hunger to break new ground brought me here. My systems exhibit that personal goal. As a pragmatist and the proprietor of a small humidor controls company, I am constantly reminded of the restrains brought about by the economics of paths established. It is not easy to be the black sheep, or the lone wolf!

As one can see, I don’t use the freeway! My paths are groundbreaking and less traveled, but alas they are confined by what is commercially produced, if I don’t make it myself, in order to circumvent an economic roadblock. My wish of course is that neither my customers nor myself were constrained by the nuisance of a budget or by monetary influence. Wishing however does as much good in a business model as it does in humidor design theory!

PID control is also a topic in and of itself. Practicality here again raises its ugly head. In our world we are not dealing with sophisticated chilled water systems, variable speed drives and PWM controls. We are somewhat limited to simple digital control systems, single sensor monitoring and limited space, not to mention budget. In a world of variable dampers, PWM controls, solenoid actuators and flow rate monitoring and modulation almost anything is possible. We could reinvent the environmental test chamber, but it already exists. What I bring into existence is a high level of control, not previously offered, suitable for the cigar enthusiast’s home and budget.

The main problem as I see it, is the use of chilled air as a means of cooling. About 90% of humidor construction problems are centered around this problem. Air heating brings with it no such problem.

The second problem arises when air exchanges happen. When you go into your humidor for a cigar, your engineering for subtle change and PID control is blown out with the lovely aroma in your humidor. PID control is after all based on keeping a control variable stable. Its primary function, not that more sophisticated algorithms could not be established, is not based on malfunction and restarts. The opening of a humidor door is akin to malfunction. In our world we have to balance rapid response with overrun and oscillation. Without absolute isolation of appliances, there are overruns and other leakage issues.

I have been working for over a year now on better isolation of appliances. A pragmatic solution will come to me I am sure. I have found nothing commercially manufactured at a low enough price point and in a small enough size to aid me in my designs. I have designed dozens of dampers… all of which I have rejected for one reason or another. Complexity, space and cost top the list!

I am holding one concept in my pocket that I am not really willing to discuss here. Like all my ideas I think it has promise. It is low cost, and should help deal with several aspects of forced air cooling but only time and experimentation will tell!

Thanks for the reply my friend. -Ray

[PigFish]

Macro and micro is an important distinction. What I imagine is building something where the macro (the room) is actively managed to a safe range but if the systems fail, that macro will still settle within a safe range. Hence the cellar idea. Normally a big deep hole in the ground is stabile for temperature and humidity, but getting it to the right humidity, passively, is a trick. Then within that room, store the cigars in humidor with passive rH systems. The immediate environment around the cigars would be consistent and always slow to change because of the barriers of boxes and humi walls and because the macro environment would be managed to desired temp and rH, with a passive fail safe environment that wouldn't kill my sticks if the whole thing died when I was out of the country for a month.

If I might mentor you a little on your design theory I will give you a little data that will save you years of heartache. If you design a classic humidor, porous in nature that diffuses water into the macro environment, actively humidify it with a small reasonably fast acting appliance AND keep your marcro environment cool, at or below your desired storage temperature AND dryer, typically 10 to 20 rH lower than your low rH set point, you will have won 95% of the battle.

A small heater in your humidor will keep that space at the right temperature and have little or no ill effect on you humidor. Heating air slowly has no real negative effect on rH.

If you keep this in mind, you will likely create an easy to maintain, well functioning humidor.

While this method seems simple, you are now controlling two environments, not just one. You are also spending the money to condition the macro environment and that can affect your utility costs. If that is of little consequence to you, then this might be the right solution.

Cheers! -Ray

[PapaDisco]

If I might mentor you a little on your design theory I will give you a little data that will save you years of heartache. If you design a classic humidor, porous in nature that diffuses water into the macro environment, actively humidify it with a small reasonably fast acting appliance AND keep your marcro environment cool, at or below your desired storage temperature AND dryer, typically 10 to 20 rH lower than your low rH set point, you will have won 95% of the battle.

A small heater in your humidor will keep that space at the right temperature and have little or no ill effect on you humidor. Heating air slowly has no real negative effect on rH.

If you keep this in mind, you will likely create an easy to maintain, well functioning humidor.

While this method seems simple, you are now controlling two environments, not just one. You are also spending the money to condition the macro environment and that can affect your utility costs. If that is of little consequence to you, then this might be the right solution.

Cheers! -Ray

That's the direction I'll go for the really big, walk-in project in the cellar. I'll have to reduce the base humidity of the cellar space somehow (additional walls, vapor barriers), but even the addition of a modest amount of heat (moving the space from a median of 45-50F to 60F) would be helpful.

Until that big construction project gets underway, I'd like to tinker with some antique chest conversions. Maybe one for the home and one for the office. The challenge for me on this, I think, is the lack of temperature stability in the macro environment (heat and a/c get turned off in both regularly, one on the weekends and the other whenever the wife leaves and wants to save $$). Of course a good old wineador would be the reasonable solution since it would come with its own cooling. I'd also need one that heats too though, since temperature drops drive rH upwards very quickly and it can get chilly here in the winter.